Author’s Introductory Note: Grid-tied solar panel payback time is less than seven years in most of the lower 48 states, and quickest in some of the New England states, so don’t think solar isn’t for you just because you live in North Dakota or Vermont. RUN THE NUMBERS which I’ll show you how to easily do. If you don’t care about all the details of how and why, skip to the last section called “Quick Way to Figure out Payback Time.” There are only three numbers to enter on your calculator and you’ll have your payback time in years. Then you can come back and read the details if you’re so inclined.
From time to time on SurvivalBlog discussions come up about whether or not solar panels can pay for themselves. I’ve been amazed as I’ve traveled around the country and seen so few homes with solar panels, and wondered why more people don’t take advantage of nearly-free electricity. I’ve concluded that the three biggest reasons are 1.) most people are not aware of how simple it is to install grid-tied solar panels yourself, 2.) they erroneously think they need storage batteries and all kinds of complicated equipment, and 3.) they’re not sure how to do the math to figure out if solar panels are feasible in their area.
First, A Brief Tutorial
So, let’s tackle those reasons in a quick tutorial.
First, if you can hook up an electric water heater, you can most likely hook up your own grid-tied PV system in a couple of days. Second, if you can install them yourself and follow some basic rules of frugality outlined below, nearly everybody in the lower 48 can make a home, grid-tied PV (photovoltaic) system pay for itself in 3½ to 7 years.
My philosophy behind having a grid-tied PV system is this: for now, we want inexpensive electricity and something simple to get us started in solar energy and, in the event of TEOTWAWKI, we want to be able to have the ability to convert our system over to something that will at least charge some batteries to provide lighting for our post-SHTF life, and hopefully much more than that. We are not trying to save the planet so let’s avoid that topic in the comments section please. (Note on EMP/Carrington Event later.)
What is a Grid-tied PV System?
Since there are no batteries involved, a grid-tied PV system is a very simple, maintenance-free setup. Instead of your solar panels charging a bank of storage batteries, the grid acts as your storage device. During the day when you are creating more electricity than you can use, your excess power goes out to the grid for your neighbors to use. At night, you borrow electricity back from the grid to run your home.
There are just two components: your set of solar panels and a small box the size of a desktop computer called an inverter. Three wires from the solar panels plug into the inverter, and, just like an electric water heater, four wires from the inverter hook into a double breaker in your home’s electrical panel.
I won’t go into the details of mounting solar panels since there are plenty of books and articles on that subject. The most crucial point to keep in mind is that, in most cases, the only way to make your PV system pay for itself in a reasonable amount of time is to do your own installation, or get it done “free” somehow via barter or bribing friends or relatives. The installation is not difficult. The second point to keep in mind is that you can make your PV system pay for itself much more quickly by making your own mounting rails rather than purchasing expensive ones offered by solar suppliers. I made mine from synthetic deck boards available at any lumber yard. You can probably come up with an even less expensive method.
The Parts List
I will be mentioning certain products but these are not endorsements. I have not kept up with technology since my installation, nor done any price comparing on inverters for this exercise. The point is to show that if I were rebuilding my system today, here’s exactly how I could do it, and at what price. If I were doing this for real, I would be doing more in-depth research and would undoubtedly find an even least expensive way to do it. So this is not a how-to article on setting up your home PV system, rather, a how-to article on determining the payback time on your investment with some pointers on frugality.
Here are some of the major expenses:
For our exercise, let’s install a 3,000-watt system on your property. That’s 10 solar panels which, when mounted in two rows of five, take up about 16’ x 11’. They can be either roof or ground mounted. The lowest average price now is 65¢/watt from several suppliers for 300-watt solar panels. 65¢ x 300 watts = $195 per solar panel. (A year ago I was seeing them as low as 61¢/watt at Home Depot.) Ten of those will cost $1,950 plus tax and shipping. I received an estimate of $400 on shipping so if you can buy locally, you’ll save considerably.
I used synthetic deck boards for the mounting rails but there are many ways you can approach this.
We’re going to need different kinds of hardware variously known as “fasteners.” Based on what I spent, $200 will more than cover fasteners, plus another $60 for conduit, wire, and mounting the inverter.
For the inverter, let’s be frugal and buy a brand-new SunnyBoy 3,000-watt inverter off eBay for $640 which includes shipping. This one lacks the “secure power supply” which gives you some power even if the grid goes down temporarily. But at $1,200 extra, there are much less expensive and more reliable ways to get power during an outage.
With tax and other miscellaneous, the total installation cost comes to $3,903. If you’re paying taxes to Uncle Sam in 2020 then you qualify for the 26% rebate which lowers your cost to $2,888 if you begin installation this year. (Next year it drops to 22%, then disappears in 2022.) That total is for my location where the local government minds their own business. If you need permits and are required to do other hoop-jumping exercises, add those costs to your total.
How Much Electricity Can I Make?
Now that you know the cost to install 3,000 watts of solar panels, the next question is, how much electricity can I generate? Once we can answer that, we’re just one step away from knowing how quickly your solar panels will pay for themselves.
How much electricity your solar panels will generate is dependent on a variety of factors, the most important being your geographic location. In order to maximize your output, you’ll want to mount your solar panels in the sunniest location available, facing as due south as possible, and mounted at an angle that matches as closely as possible the degrees of your latitude. But everything doesn’t need to be “perfect” so just get as close as you can on these.
Variables for Determining Electrical Generation
You’ll need to know how much sun, called Solar Irradiance, your county receives on average. Use the color-coded map above (or click here) to approximate your location, then find the number that correlates with that color. For example, where the word “Illinois” is printed on the map, that shade of yellow correlates to a solar irradiance value of 4.5-4.9. Let’s keep it simple and choose the middle value of 4.7.
That number is the average daily solar irradiance received over the course of the year. We also use a constant of 0.7 to account for a 30% loss of efficiency in our solar panels mainly due to overheating and the physics of what happens when you convert AC to DC.
So far in the equation we have our solar irradiance of 4.7, multiplied by 0.70 to account for inefficiency, and now we multiply those by our 3,000 watts of solar panels to get our average amount of electricity produced each day:
4.7 x 0.7 x 3,000 = 9,870 watt hours
In electricity, we commonly talk about kilowatt hours (kWh), which is 1,000 watts per hour, so let’s divide our watt hours by 1,000 to get 9.87 kWh.
Again, that’s a daily average only. It will be higher in the middle of June and lower on Christmas day. We now multiply that 9.87 by 365 to find out how much electricity you can expect your solar panels to produce in one year.
9.87 kWh x 365 = 3,603 kWh of electricity produced each year.
How Quickly Will My Solar Panels Pay For Themselves?
Now we only need one more number to figure out how long it will take our solar panels to pay for themselves.
You’ll need a recent power bill, or more likely, you’ll need to call your power company. How much do they charge per kilowatt-hour of electricity? Due to the meter charge, you can’t just divide your total bill by total kWh used.
Once you have the kWh rate you can use it to figure out the annual value of the electricity your solar panels are generating and thus calculate the payback time.
Currently, the U.S. national average for electricity is around 13.5¢/kWh, so let’s use that. With our solar array generating 3,603 kWh of electricity per year, when we multiply that by 13.5¢ (0.135), we get a yearly total of $486.40. That’s how much money we save each year by generating our own electricity. By dividing our total installation cost by how much the electricity is worth each year, we find our payback time:
$2,888 / $486.40 = 5.9 years to get our money back w/IRS rebate
$3,903 / $486.40 = 8.0 years to get our money back if no IRS rebate
Ironically, some of the best solar-producing areas of the country have the longest payback times because they also have cheap grid power. The New England states have some of the shortest payback times due to high energy costs. So don’t make any assumptions about solar before you run the numbers for yourself.
Once we have paid off our solar panels, we’re now generating $486.40 of free electricity each year. Since we’re now more comfortable with solar electricity, and we’ve been working on lowering our electricity needs (I’m down to 100 kWh/month), we can use that money to start buying components to convert to an off-grid system which is more EMP-proof. In the event we don’t convert to off-grid before the SHTF, as long as TEOTWAWKI is something other than a solar-panel-frying EMP/Carrington Event, we’ll still have workable solar panels to charge batteries, have lights, run water well pumps, etc. by using less expensive smaller inverters.
A Quick Way to Figure Your Payback Time
Formula:
$2,888 ÷ (DNSI x kWh cost x 767) = your payback years
Formula Notes:
- If not getting the IRS rebate, use $3,903 instead of $2,888. Add to this any permit and hoop-jumping costs your area may require.
- DNSI is the average solar irradiance for your area. See the map, above.
- kWh cost is your current kWh cost for electricity. Ask your power company. Be sure to use a decimal amount in dollars. (e.g. 0.135, not 13.5¢)
- 767 is a constant based on a 3,000-watt solar panel system, a 70% efficiency factor, and 365 days in the year.
Here is a chart showing some sample payback times in various parts of the country based on different kWh costs for electricity. This chart is only a rough ballpark idea of payback time, so run your own numbers to be more exact. If you like what you see, then come up with a more precise number of payback years by using your estimated total system cost instead of the $2,888 presented here.
Summary
Don’t sell yourself short when it comes to solar electricity! People think solar panels only work well in the Southwest, but nothing could be further from the truth. They pay for themselves much more quickly in the Northeast where grid electricity is expensive. Grid-tied solar panels are very easy to install yourself. If you can install an electric water heater, you can almost certainly install your own PV system. If you can’t, one of your friends or family probably can.
Get your feet wet with a super simple, grid-tied PV system and then work towards a more independent system which is EMP proof. Do it now while the IRS rebates are still in place and Uncle Sam will pay for 26% of your costs. (By taking less of your own money.)
Most fuel-based electric-generating systems won’t last long in a grid-down, Patriots/Alas Babylon situation. You can only store so much fuel. Solar panels are guaranteed for 25 years and even then they keep working, just at a lower efficiency. While electricity isn’t a necessity, it will sure make transitioning to life after TEOTWAWKI a whole lot easier. Especially with the Andrews Sisters harmonizing in the background and Charlie Daniels belting out, “Mario Andretti woulda’ sure been proud the way I was movin’ when I passed that crowd, and just for fun I chased ‘em once around the parking lot!”
Let’s hope your spouse isn’t chasing you around the parking lot for not getting those solar panels installed when you had the chance. Hard times are coming!
Well written article – clear and straightforward, and easy to understand how to evaluate making an investment in solar. I checked my current electric bill to see how much electricity we used last month – 795 kWh – we’re in Texas just easing off on the high heat and resulting AC requirements – but when you mentioned your 100 kWh per month usage, I was floored – how could that be possible?
Hey Joe,
Your comment made me chuckle because I look at the average American usage of 970 a month and wonder, how can that be possible? lol. I could write an article on how I do it but here’s the quick overview.
For me, it’s a big game and a challenge to see how little electricity I can get by with. As As I’ve mentioned many times on SB, my goal for self reliance is to be living as low tech as possible so that when TEOTWAWKI hits, I’ll only have to make some slight changes, compared to the rest of the world which will be panicking.
I get by just fine without a lot of the conveniences that Americans consider necessities, which none of our ancestors had. I don’t have AC for example, even though 90% of the folks in my county do, so that alone is a huge savings. This month I was on track to only use 80 kWh per month, then used my table saw a lot at the end of the month so now I will finish tomorrow at 89 kWh.
I have the meter linked at the bottom of my comment here. It lets me measure the actual usage of each appliance by the day or month. By using that, I can see where the hogs are and what’s not using much. A big surprise was my full-sized refrigerator/freezer only uses 19½ kWh per month. My desktop computer, uses 15, DVD + TV uses 16 so by switching to a solar-charged laptop for computing and DVD watching, I could reduce my usage by another 31 kWh per month. The wash machine uses 4.8 and I don’t use a clothes dryer, another huge energy hog. Even though I live in a rainy area, I can still line dry my laundry 52 weeks of the year. My well and pressure pump use 22 kWh, my single biggest user. Microwave, 5.3. Lights are all LED and since I have skylights in both my house and shop, I only rarely have lights on during the day, and at night, only where I am actually working or relaxing. My propane stove was especially selected with off-grid in mind and uses 8 AA batteries instead of plugging into the wall. Since pilot lights were outlawed, your oven is expensive to run because there is a glow bar instead of a pilot light, and that uses a lot of electricity.
Probably the biggest electricity user in many homes is an electric water heater. The big yellow sticker on mine says it will average about 393 kWh per month. Nine months of the year I use a solar water heater and when I do use the electric water heater, I control it manually instead of leaving it turned on. So instead of using 13 kWh per day, I only use 0.375 kWh per day by only turning it on for five minutes, then shutting it off. That creates a pocket of hot water in the top of the heater, just enough to take a hot shower, but I have to go in and take it immediately before the hot and cold water start mixing in the heater tank.
My lowest kWh usage months are April, May, September and October when I am using neither the wood stove blower or a cooling fan and my yearly average is right around 100 kWh.
The only inconvenience as far as electricity usage goes, is that the month of July tends to be barely bearable without AC, but I am usually working outside all day and it’s miserable out there as well. I compensate indoors by using a 92 watt box fan.
My advice is people is to try out all of these methods for a month so that when the SHTF, they will be in your memory banks and will be easier to draw upon then something you merely read about years ago. And have fun with it, it’s quite the challenge for most.
Here’s the $24 electricity usage meter:
https://www.amazon.com/Poniie-PN1500-Electricity-Electrical-Consumption/dp/B07VPTN8FZ
Well written article by St. Funogas explaining how to calculate the financial costs of a ‘do it yourself’ Solar System Installation.
The method can also be used to calculate the benefits and expense of paying a company to install it, ~or paying someone else to help you install it.
Besides the Federal Government, many State Governments allow a percentage Solar Install tax credit, for people paying State Income taxes. Plus, quite few Electric Utilities have rebates to offset the expense of an installation.
Electricity is a life saver for many people. Many necessary life saving medicines need refrigeration for prolonging the ‘shelf life’ of the medicine. … Food safety is also enhanced with an icebox.
… … Many people could consider buying an new or used RV Refrigerator that can be powered by batteries [Charged by the Solar System]. … … Also, many RV Refrigerators can be powered by propane stored in tanks too.
******
******
Anyone spending the money for a Solar System, should also look into installing an Electrical Surge Protector.
I don’t have a Solar System, but I have a Surge Protector for my inexpensive Walmart Computer.
A Solar System is a ‘survival’ item, that can put money back into your wallet, over the Solar System’s life expectancy. [A real good prep]
… … +Right now, there are a lot of people making money on trying to destroy the successful economic capabilities of United States. Obviously, many foreign governments financially support our destruction too. [They WANT expensive Utility bills in the USA.]
Millions and Millions of Americans in 2020 will be voting for a Make ~>China Great Once Again economic policy. … In my State, the Crackpot Politicians have already voted to outlaw ~privately owned, NEW, gasoline powered cars in 2035. +There is an actual plan to roll back the advantages of Western Civilization.
…. … Don’t worry if you’re healthy and strong, there’ll be jobs available carrying the wealthy around in human powered Sedan Chairs. … [Electrical Cars are actually bigger polluters than Gasoline powered Cars. Look on the Internet for an explanation of the >true economic cost of Electric Cars. Privately, owned Electric Cars will face the Guillotine too in the future.]
Even a small Solar Panel can power a Shortwave Radio. Lack of reliable information is like fumbling around in the dark without a flashlight. … Solar Power can provide electricity to your home, completely independent from the utility supplied electric grid.
It’s taught in our school systems, that there are too many people in the world. A lot of Americans have been convinced, they have a ‘religious duty’ to Save the Earth, and help kill-off billions of people. … An Economic Death of the USA seems to be the first step in the evil plan.
……. [Something to worry about, even though, St. Funogas didn’t want the ‘Save the Earth’ kookburger~ideas mentioned in the comment section.]
Hey GGHD, lots of good comments.
I have several small solar panels for experimenting with as you recommend. Even those will be worth their weight in gold when the SHTF and can do much. I kept an old worn out battery from my truck that I didn’t return to get the core charge on, and using a 25 watt solar panel, was able to charge the battery and then run a floor lamp for 41 hours straight using a very small inverter I bought at an auction for $5 similar to the one linked below. I got five years out of that worn out truck battery using it for other projects such as running the 12v water pump for solar and rocket water heaters.
And thanks for mentioning the state rebates, the will speed up payback time even more.
My personal philosophy on propane is that in a permanent TEOTWAWKI situation, propane will be worth its weight in rhodium and I have plans to only use it for cooking, nothing else. So I would get a small electric fridge, based on the lowest electrical usage possible. I will personally learn to live without one as our ancestors did, but as you mentioned, many life-saving drugs must be kept cool. Perhaps in that situation, both propane and electric fridges on hand would be the best option, a life being more important than the inconvenience of cooking over a campfire in the back yard.
https://www.amazon.com/Tripp-Lite-Inverter-Compact-PV150/dp/B0000AI0OE
“In my State, the Crackpot Politicians have already voted to outlaw ~privately owned, NEW, gasoline powered cars in 2035”
And this is in a state that produces very little, if any, of their own electricity.
At the rate people are fleeing California, will there be anyone left in 2035? 🙂
I live in Vermont and had a grid tied battery backup system professionally installed last year. There are 33 325 watt panels and 2 Tesla batteries. I have not had an electric bill all year (except for the $12/month connection fee). As of this morning I have generated 11,672 kwh, I have used 6,035, so I have generated 193% of my homes usage. That extra generation is applied as a credit that I can use within a year. I have a heat pump for cooling and heating, those credits will be used to heat my house for the winter. Imagine that, in Vermont I have no electric bill, no cooling bill, no HEAT bill. If its a no brainer to install panels in Vermont I can’t understand why everyone in the southwest doesn’t have them.
I wouldn’t install non battery backup grid tied system, when grid goes down you don’t get any power no matter how much sun is shinning.
Hey Carl, thanks for the testimonial.
I tried to find a map for the article which I was unable to find, but now I’ve found it. You see all the time maps of solar irradiance such as the one included in this article. People glance a t that, notice they aren’t in the nice dark orange areas, and conclude that solar power isn’t feasible. What they fail to realize is that electricity cost is just as important as their solar irradiance as seen on those maps.
In the map link below, you can see the dark areas which mean high electricity cost, are all in New England states, and some of the southwest states. Those states will have just as quick of a payback time as the ones in high solar irradiance areas, or quicker, since the electricity costs twice as much but the solar irradience in less than twice as much.
“I wouldn’t install non battery backup grid tied system, when grid goes down you don’t get any power no matter how much sun is shining.”
One thing worth checking into is the cost of a “secure power supply” for the particular inverter one is buying. I didn’t do any checking, just on the Sunny Boy inverter I mentioned. A secure power supply still gives me 1,500 watts during the day even when the grid is down. It’s not worth the cost for anyone trying to keep as low-budget as possible, but is a good backup for those not able to get completely off-grid before the SHTF.
Two Tesla Batteries at $20k each = $40,000
33 325 watt solar panels at $405 each = 13,365
estimate on the rest of the installation exceeds $15,000
Wait a minute! I think we figured out why everyone isn’t doing it.
The LG batteries are running between 7-9k and seem to be a superior product, but still not a cost effective solution.
$7-9k for replacement batteries. That means they get your old battery to rebuild. If you don’t have a ‘core’ to turn in the price is $20k.
That’s not accurate.
LG Chem RESU10H 9.8kWh 400V Battery
LG Chem RESU10H Lithium Ion Battery 400v 9.8kWH 63Ah
$6,300.00
That is the price that is readily available through multiple sources. No trade in required.
The Tesla model S battery is $19,999 without a core trade-in.
$40,000 for tesla batteries? I got mine from my power company, Green Mt Power, they were $3,000 up front for 10 year lease, after 10 years they are mine. Only catch was when they need power like during hot humid evening when people come home from work, they take the power from my (their) batteries. If there’s a storm fore cast they will not take power. They then recharge batteries later that evening. Power here costs 17 cents a kwh. My system completely installed cost $33k, I received an $11k tax credit. A price of $22k for complete electrical freedom, to me, is well worth it. I may buy an electric car in the future and will power it with a few more panels (which are getting cheaper every year).
Hey Carl, have you had your system installed for a complete year yet? I’d like to know what percentage of the power you produce per year you actually use.
I keep monthly records so I can compare one July to any other, as well as determine monthly and yearly averages, not to mention play around with Excel. Based on my yearly usage, I could have built a smaller, cheaper PV system. In hindsight, I should have been trying to reduce my usage long before I started building my house, so I could have had a truer picture of what exactly I needed. On the other hand, 25 years from now when the panels have lost some of their efficiency due to aging, I’ll still be in good shape.
Make sure to check the net metering tariff for your specific utility prior to calculating your payback period.
While many residential net metering tariffs do offer a 1 for 1 credit during periods of overuse (essentially “rolling back” your meter), not all do. In some cases the credit that you receive for overuse that flows out to the grid will be calculated at the applicable hourly wholesale commodity only rate per kWh (hourly LMP) rather than a derived per kWh based on your utility invoice while you will be charged the full per kWh rate when you “get the energy back” from the grid.
Hi Grey Woman, those are good things to check into. In my area, fortunately they do offer a 1:1 credit. But on any electricity I sell to them which I don’t need back, they only give me 25% of what they charge for a kWh they sell to my neighbors. Some areas I checked into won’t give you anything for the extra watts.
That brings up another important point. I used a 3,000-watt system in the article because any system that creates electricity below or equal to your annual needs will pay for itself based on the formulas presented here. If your system produces more than you need, the payback time is longer. If you’re not concerned about cost, then overproduction can be of use in a TEOTWAWKI situation by charging your neighbors (pun intended) a fee to recharge their portable batteries such as car batteries (which have uses elsewhere using the small $35 inverters), and rechargeable AA, AAA, D, etc batteries.
If considering, please listen to Ms. Grey. Before we installed our solar array this summer (COVID project), we called our co-op and we were told that they did net meetering. After receiving the first bill after install though, they bill as Mr. Grey explains. This effected our pay back period very drastically. Still glad we installed.
Where i live, the Tennessee Valley Electric Cooperative has stated to me that they do NOT want grid tied solar on their system due to the dangers to their employees. I can understand that. They have stated that I either need to be using their grid power or to get completely off grid. So, I am thinking that I should build the solar system as a back up to the grid, and then disconnect the incoming grid power in an emergency or permanent grid power loss and use the solar as needed. There would be no payback intentions. I live very conservatively alone and I thought my electric usage was pretty low at an average of about 385 kWh per month, but 100 kWh per month takes the trophy.
Hi Jima, I would double check that you cannot grid tie. I was under the impression that because of green laws (which I disagree with 100%) power companies had to let people grid-tie.
In my experience, power companies do all they can to discourage people from going solar. What your power company is telling you about injuring line workers is totally incorrect. Grid-tied inverters must be what’s called “UL 1741 compliant.” That means that the inverter will quit feeding electricity to the grid within a second or two whenever the grid goes down. That makes it impossible to back feed into the grid which could injure line workers who are ignoring the rule of always treating lines as if they are live.
My electric co-op sends me a form once a year where I have to certify that I have manually tested the system and that the shut down time is two seconds or less. I test mine by shutting off and then back on as quickly as I can, the main power switch so it’s probably off for less than a second. And the inverter always shuts down.
As you mention, I built mine with self reliance in mind, not payback time.
jima,
States that use the National Electric Code (don’t all of them use it?) would require an automatic disconnect that disconnects the solar power from the grid if the grid goes down. That eliminates any danger to linemen.
Great1 Thanks for the information. I will double check with TVEC
Hui Jima, I couldn’t find any info on their website but I did get an email response back with a link.
Here is a link with some of the initial info for grid-tying home solar panels.
https://www.tva.com/energy/valley-renewable-energy/dispersed-power-production-program
Some power companies/co-ops are much easier to work with than others. I called a bunch of them and looked at their websites while writing this article and researching for friends and relatives in other states, and no two were remotely similar. Good luck and be persistent!
Hey Riverwood, now that you mention it, aside from requiring UL 1741 compliance for the inverter, my local co-op also required me to install a manual shut off right below my meter. It’s totally redundant to require both but they do it anyway. At least they sold one to me at cost, $225. Luckily I had not yet hooked my house up the grid so the switch was easy for me to install when I did finish the house and hook up. Now I’m in the process of getting off the grid completely. Not paying $360/year in meter fees will help pay for the things I need to accomplish that.
We had a solar system installed in 2018 in the metro Phoenix area. The key (in my opinion) was finding a situation where we would own, not lease, the system. Costco provided that and so we started. It was a fairly long process but very detailed. In this area, you have to be grid-tied. Also, there was no way that the “CEO” was going to let me get up on the roof and attempt this project, so that savings aspect wasn’t happening.
We were spending about $250 per month on electricity. This year we’ll break even or even be slightly negative, saving about $3,000. If that schedule holds true in the coming years, the payback time for our system would be about 9 years. It would be half that if we subtracted the labor cost. That puts our scenario right in line with the article author’s payback. There is still a rebate program with the federal and state government, but it’s being changed and/or phased out, so prior due diligence is required.
Hey Saratoga, thanks for the feedback and testimonial, and for underscoring that rebate programs are running out. As you mentioned, the laws vary widely and due diligence is needed.
Your CEO comment made me smile. One of my past CEO’s would have said, “Of course you’re getting up on the roof! We need to keep this as cheap as possible and we have workman’s comp if you break your neck.”
Grid-tie solar is OK for the reasons mentioned….reducing your power bill. But anything connected to the grid will not fare well if we ever get an EMP attack. E1, coming off of power lines at your house, will flash over 22 inches of dry air. How far apart of the terminals in your electrical panel? Not very far. In any event, have SPARES of everything. Mainly to rebuild your own off-grid system. Battery/batteries, inverter, charge controller, panels. Use MC cable (conductors shielded inside flexible metal conduit) for conductors to prevent RF coupling of EMP/CME. Solar panels are pretty resilient against EMP if they are not wired, or if the conductors are shielded. A forklift battery, or a bank of conventional batteries, act as a filter that helps protect your inverter. The wiring in your house, however, acts as a nice antenna, also. New constructions should employ MC cable throughout for the same reason.
Forklift batteries last many decades longer than solar batteries wired in a bank, especially if you take care of them and operate them within the top 15% of their capacity. Cheaper up-front, too!
Not a fan of the Lith-ion Power Wall and others like it. Too many circuit cards inside to regulate them. These don’t like surges. I’m not a fan of attaching potential fire sources (outside of my wood stove) to my house, either.
Funny thing, none of my super-liberal contacts have solar or drive electric cars. Some of my conservative contacts, DO.
Hi Paul, lots of excellent points. Even a couple of 300-watt solar panels as backups would be a big help in a SHTF scenario. If the Chinese/Russians can hold off that EMP attack, and the sun that Carrington event, my own plan is to have a minimum of two backups (preferably 4) in my concrete-roofed root cellar in two years. If things start looking dicey, I’d pull some of the ones off the shop roof and put them in the root cellar.
You mentioned good ideas for new construction. Another thing to keep in mind when designing a house or shop is to build the roof angle at the precise solar-panel angle you need for your area, which is the same degrees as your latitude. I did that with my shop, along with building it facing due south, knowing I’d be adding solar panels once the house was finished. Both of those things help to maximize efficiency.
St. Funogas,
The concrete root cellar offers no protection against EMP effects. EMP is known to penetrate up to 20 feet underground, and even the control cabling used on Minuteman systems, buried to 88 or so feet deep, are shielded.
But your standard panel will not collect much RF at all just sitting in the garage, unwired.
I tried the roof top mounting system, though it was elevated at least a foot above the roof of a shipping container and angled to 45 degrees. I thought 12 inches might be enough standoff to avoid snow issues, but I was WRONG. Snow sliding off the panels would accumulate and block the rest of the snow load from sliding free. Eh. Trips atop the container to shovel and broom the snow free inspired me to build a second array on a pole top mount, which self-clears within 90 minutes of direct sunlight no matter now cold it is. I note the time it takes to clear roof-top systems in my urban neighborhood, and it often takes several days.
The pole top mount does not damage your roof, clears itself rapidly, and doesn’t have to be removed periodically to repair or replace the roofing materials. They are also quite easy to alter the angle of attack to harvest the maximum amount of sun from one season to another, although I’ve just left the panels at their winter setting for several years now. Call me lazy.
There was a Texas solar farm that recently got hit by a hailstorm. Several thousand panels were damaged by very large hail stones. The insurance company decided to replace ALL the panels. So the undamaged copies, over 10,000 acres of them- are on the market right now as “take-offs”. They are about 15 months old, made in Korea, and are quite good. 345 watts, 35 volts, 34 1/2″ wide, 78″ tall. Most are selling around the country for $150.00 each. I bought 40 of them for spares, divided up among a few friends. Since my supplier was 15 minutes away, I had no shipping expenses.
Anything people can do to go solar, particularly off-grid solar, is a step in the right direction, since, as you pointed out, the supply chain will prove unreliable in many scenarios. Generators, and in short- anything that moves also breaks, even if you had enough fuel to last a long time.
Thanks for pushing on solar. Hope more take this opportunity to get off-grid, even if just for a backup system.
You could build your panel system in stages by isolating the circuits you are powering using a “solar dedicated” breaker box. St. Funogas illustrates the idea by breaking down the usage of each of his items that requires power and picks one to move to solar power. To start, a few panels could run your refrigerator. As panels are added, other circuits could be moved from your original breaker box to the solar box. You would need to keep the finished size of your system in mind to size your panel space and wire size with the initial install. A couple sizes of inverters would be needed as the system grows to keep things efficient. I enjoyed the article. Thanks for sharing it.
This is basically what I did. When I bought my house, a sub-panel had been installed for an addition. I re-wired the sub-panel for all my lighting, and some outlets. I connected my inverter to this panel via an interlock breaker. The sub-panel can be powered either by the main electric panel, or the inverter, but not both at the same time. I chose a battery system rather than grid tied for a couple of reasons. One, the power was out in the area my house is for 2 weeks while the house was in escrow. I wanted back up power. Second, I could do the off grid myself, I would have had to get permits and a special disconnect switch for the grid tie in order to automatically disconnect my power from the grid if the grid power went down. (Safety for the Linemen.) I will eventually have a setup where my freezer and refrigerator will be on the solar side also. I have a propane range, and wood heat. My heat pump, a mini-split, is able to run off my solar, but only during the day when the sun is shining, so I could have A/C if needed. I also have the capability for generator power if my batteries are undercharged due to lengthy cloudy days. My only issues will be water, I’m on a well, and hot water, I have an electric water heater. I have a simple pump and will be getting the solar option for it, so that will take care of my water issue. I can get by without hot water, but do have a portable on demand propane water heater that I can use if needed.
Hey JGinTex, that sounds like a good way for some people to afford solar, buying it one piece at a time. (Wasn’t there a song about that?)
I assume you have a pressure pump with your well? My well pumps into a 250-gallon tank in my well house and I’m looking for a better off-grid way to get water to the house without a pressure pump, which uses a lot of electricity and has a major start-up surge.
We installed a 3000 watt system in March of this year. It is not grid-tied. It does have a sealed lead-acid battery bank. I shopped around a lot and did the installation myself. We did this as a 100% prep item. Total cost for the system was around $6000. We run a few critical house circuits on the solar (mostly the refrigerator and a freezer). Before install we roughly used about 240kwh per month. Since install we use about 220 kwh. Our prior monthly bills averaged $50 and now average $45. Our monthly hook-up fee is always $31 of that. We pay .0735 per kwh (plus taxes). Our total payback will occur in around 100 years.
Again we both knew this was an incredibly stupid economic move but did it only for the prep reasons. The system cannot and does not run our well pump. We do get occasional power outages here. The electric line ends at our place. In the six months of operation the system has not had any issues and this was the worst time here for solar due to the summer monsoon season.
“Again we both knew this was an incredibly stupid economic move…”
Hey Pete, gotta disagree with you on that one. The satisfaction is probably worth more than the $6,000. People buy brand-new vehicles for tens of thousands of dollars, just for the satisfaction. After Tunnel Rabbit, I’m probably one of the most frugal folks on SB and I would call the purchase of a brand-new vehicle “an incredibly stupid economic move” but that’s just my opinion and for those people buying them, it provides a sense of satisfaction of some sort, so not necessarily an incredibly stupid economic move for them if they have the means to do so. Most people probably blow $6,000 on junk and at the end of the year they can’t even tell you where it went. So IMO, if people have the means, solar panels are a great way to spend some money, and if they end up paying for themselves and more, then it becomes an investment. And if the feces hit the fan, you’ll definitely get the last laugh over the guy with the brand-new 4WD truck and no gas to put in it and nowhere to go if he had the gas.
Just my 2¢. And congratulations at using only 200 kWh per month. I’ll stay off my soapbox and not talk about the meter fees you mentioned, but those are merely to subsidize electricity the really big customers. When it happens in a co-op, which is supposed to be We the People and not a for-profit business, that’s just not right.
Hopefully you can run the well pump on a generator.
I’ve been off-grid capable with grid-tied option for about 5 years now.
It’s a terrific feeling knowing that other than the hot tub, the electric range and the clothes dryer, I can power my normal daily uses indefinitely without the usage of the grid or a generator.
I do also have a gen, and plenty of (all types) of fuel, (Todd Gray style) – but I can save those things for what they are best used for, not making electricity.
I DO have to climb up on the roof and shovel off the solar panels during the winter at least two times to keep the snow load reasonable, as my roof only has a 3/12 pitch – and the snow WILL NOT slide – no mater how much I wish it would. It will slide early season if we get a few inches and then get some sunny days, but as soon as the real snows come, “forgetaboutit”! 🙂
I have enphase micro inverters – and a Magnum inverter – but I encourage people who are about to do this to call Magnum and talk to Darren Massey – their lead tech and seek his advice.
https://www.magnum-dimensions.com/contact-power-conversion-solutions-team
Ask for Darren Massey in tech. They have some very cool new products that make this easy…. even their own microinverters to compete with enphase.
Just tell them you want to be grid tied for cost savings reasons – but want battery backup for all the obvious reasons.
I’ve got lead acid batteries as the lithium wasn’t ready for prime time cost wise 5 years ago when I did mine.
Lead acid still works! and it’s a lot cheaper – so consider it if costs are tight.
If you have the money – go lithium – such as the tesla power wall….. OR large lithium 12v solar batteries.
The powerwall is a lot more “connected” than my system… which is not in the slightest depended on “the interwebs”.
Power is nice to have – seriously consider pulling some cash out of the market and go into this tangible … its the only investment that I can think of that pays you in non-currency… this one pays you back in KWH! (like having an oil well)
Also – for a generator – look at the Honda ultra quiet models..
and then look to enclose it in a concrete hut… with torturous paths for air inlet and exhaust …. whhhhisper quiet – I can’t hear mind past about 30 -40 feet.
Godbless!
Hey Tom, lots of great input.
“Power is nice to have – seriously consider pulling some cash out of the market and go into this tangible… ”
Amen Brother. I used money from my 401k, gladly paid the penalty and taxes to build my house and put my PV system in. I realize normal folks wouldn’t do that but like you said, self-reliance and being ready for anything is a great feeling and IMO, worth way more than a worthless piece of paper with $$ on it after the SHTF.
One thing I do for snow, and not sure if this would work with your 3/12 pitch, is to take a piece of 1″ x 20′ PVC and scratch a few lines of snow to reveal the black panel beneath. They’re obviously not very wide but they let in enough sun to form a layer of water and soon enough, the snow slides off. I also have a hose valve on my shop right at the base of the wall where the solar panels are. On cloudy snow days, I turn that on temporarily, and using a brass sweeper nozzle ($3), wash some of the snow off, then drain the hose and turn the water back off in my well house.
Have you thought of any wood heat options for your hot tub? I’ve got a spot for my hot tub but haven’t constructed it yet and would like some first-hand wood-heat experiences from someone. I’ve got a rocket water heater but it would take a long time to heat up that kind of water volume.
Thanks again for your comments.
EMP Shield has a surge suppressor that reacts fast enough to protect against EMP attacks. They indicate it has been tested. Their website is http://www.empshield.com. You may be able to install it yourself.
If anyone clicks on the EMP Shield ad at SurvivalBlog before ordering, then we’ll earn a small commission. Thanks!
Hey F, those are much more reasonably priced than I would have expected, plus they protect against lightning strikes as well.
If you go to their website and vote on the coolest think made in Kansas, you’ll get entered in a contest to win a free EMP surge protector. The ad JWR was referring to is in the green margin on the right of the SB screen, about the 5th ad up in a blue box. If you click there and end up not buying, they’ll at least know that their ad on SB is drawing some attention.
Perhaps St. Funogas will forgive me for being a bit off topic. As a hard core survivalist, the topic inspired me to present another perspective.
After pumping water, keeping radios operational is the most important reason to have photo voltaic panels. However, we should also understand their limitations, and plan accordingly. It may be necessary to have a small whisper quiet Honda generator to support your communications during the long dark winters of the north. However, these are expensive. Some generators can be adequately quieted if certain techniques are used to deflect the noise such as snow, dirt, bricks, concrete blocks, or stacking rocks around the generator. This absorbs and deflects the noise upwards, and reduces the noise heard. My set of old 1985 Honda EM500 generators are quiet enough that this is usually not necessary. As gasoline will be in limited supply, the generators would only be used to supplement during the winter. Solar power is a must have longer term as generators need fuel, and can, and will break down. Yet solar power or generators, may, or may not be the only source of power. For example, a human powered bicycle that turns a Chevy one wire alternator, or other alternative means to generate power, should also be apart of your planning. Remember P.A.C.E?. For your consideration:
In my experimenting, a Boafeng UV5R can be run directly from a 10 watt panel in full sun with a ”battery eliminator”. This is the most electrically efficient method. This radio requires only .51 amps when transmitting with 4 watts. It uses only 250ma or less, or about 1/4 of an ampere at 7.4 vdc when receiving, and only 75ma when on standby, or listening. At best, during periods of thick cloud cover, a photo voltaic panel will only produce 10 percent of it’s rated maximum output. In other words, a 100 watt panel would produce, at best, under heavy cloud cover, only 10 watts. Fortunately that is just enough to charge a Baofeng UV5R with a 1800ma battery in less than 2 to 4 hours. Several inexpensive transformers, or adapters that drops the voltage from 12vdc to 9vdc that the Boafeng charger can use without becoming damaged, would be more efficient than using a small inverter. However, there will like not be a 100 percent efficient system in use as there are many devices that need power and could be used in providing security. Plan for the worst, and for a less than 10 percent production from a solar panel for a variety of reasons. And assume that a less efficient system for supplying power to other devices will be much less efficient, perhaps only 50 percent efficient. Anytime power is stepped up or down from one voltage level, or converted into a chemical form and stored in a battery, there is a loss of power. To be safe, I de-rate the panel by 50 percent. If operating where the winters are long and dark, and in the case that only ‘solar panels’ would be the only source of power, I would recommend that for each Boafeng radio in use, that two 100 watt panels be available to recharge it’s 1800ma battery. With this as a ‘given’, we can see that solar alone during the darkest part of the winter, might not be enough, as the number of PV panels needed to support two radios would have to be at least four 100 watt panels.
If charging deep cycle batteries and then charging Boafeng batteries, reduce the estimated power available by at least 20%. Deduct another 30 percent if an inverter is used. Avoid using inverters if possible. During the darkest part of winter, with only one 100 watt panel we could expect to charge between 0 and 1 Boafengs per day. With two 100 watt panels, 1 to 2 Boafengs might be recharged. How many that can be charged is wholly dependent on the ‘Insolation’, and latitude. Field phones would provide better communications security (COMSEC), and use less power. A combination of field phones and hand held radios, and other means, and at least one alternative means of producing power increases reliability, and capability. In all actuality, solar power is inadequate, or an unreliable means of powering a communication system needed for security operations during the darkest part of winter in NW Montana. A large bank of storage batteries that could also provide power into the winter is unfortunately outside my small budget, but perhaps not yours. And perhaps a diesel generator is within your budget. I can only afford a small bank of two 6 vdc deep cycle batteries that is quickly charged by a small generator that only needs to be run a few hours at most per day, and let the solar panels top off the batteries, or provide the bulk charge when the clouds are not so thick. This small ‘system’ allows the operation of many scanners, a mobile, recharges AA batteries, and other devices, and even power an HF set if needed. If storage batteries were not available, a small Honda generator could recharge all devices directly, and PV panels could assist by providing power directly to radios on standby. This method would not be less energy efficient in terms a gasoline use. And at a minimum, I would have at least four 100 watt panels that could be counted on to keep 2 Boafeng radios running during the darkest part of winter in NW Montana. This is what I consider to be the smallest set up that could provide an adequate amount of power to keep security up if only radios are available. Use field phones to replace the radios, and the power requirement approaches zero.
Renology 100 watt PV panel, $100
https://www.amazon.com/gp/slredirect/picassoRedirect.html/ref=pa_sp_atf_aps_sr_pg1_1?ie=UTF8&adId=A011650829XW0MBK56O60&url=%2FRenogy-Monocrystalline-Solar-Compact-Design%2Fdp%2FB07GF5JY35%2Fref%3Dsr_1_1_sspa%3Fcrid%3D34FMROVQ8ZJXF%26dchild%3D1%26keywords%3Drenology%2B100%2Bwatt%2Bsolar%2Bpanel%26qid%3D1601219724%26sprefix%3Drenology%2B%252Caps%252C236%26sr%3D8-1-spons%26psc%3D1&qualifier=1601219724&id=935287335902665&widgetName=sp_atf
30 amp charge contoller $12
https://www.amazon.com/gp/slredirect/picassoRedirect.html/ref=pa_sp_btf_aps_sr_pg1_1?ie=UTF8&adId=A00769301NHKV6AESTZLF&url=%2FLinkhood-Controller-Intelligent-Multi-Function-Adjustable%2Fdp%2FB07X5KL5TH%2Fref%3Dsr_1_22_sspa%3Fcrid%3D128OI8MGEY6QL%26dchild%3D1%26keywords%3Drenology%2B20%2Bamp%2Bcharge%2Bcontroller%26qid%3D1601219566%26sprefix%3DRenelogy%2B20%2Bamp%2Bcharg%252Caps%252C190%26sr%3D8-22-spons%26psc%3D1&qualifier=1601219566&id=6586531861122776&widgetName=sp_btf
300 watt Inverter, $26
https://www.amazon.com/gp/slredirect/picassoRedirect.html%2FB07X5KL5TH%2Fref%3Dsr_1_22_sspa%3Fcrid%3D128OI8MGEY6QL%26dchild%3D1%26keywords%3Drenology%2B20%2Bamp%2Bcharge%2Bcontroller%26qid%3D1601219566%26sprefix%3DRenelogy%2B20%2Bamp%2Bcharg%252Caps%252C190%26sr%3D8-22-spons%26psc%3D1&qualifier=1601219566&id=6586531861122776&widgetName=sp_btf
300 watt Inverter, $26
https://www.amazon.com/gp/slredirect/picassoRedirect.html
Hey Tunnel Rabbit, you sound pretty on topic to me. 🙂
You make some important points about where system efficiency is lost.
I couldn’t get the bottom two links to work, can you check those? I’d like to take a look at those $26 inverters.
Which type of sine wave can radios use? Here is a modified sine wave inverter for $24. It’s easy enough to adapt the cigarette lighter plug or cut it off completely and strip the wire leads.
https://www.amazon.com/BESTEK-Inverter-Charging-Converter-Cigarette/dp/B07L1G2MQV#ace-2545694624
You also mentioned watts produced at different levels of cloud cover. That’s something I still need to test and keep notes on. Better now than when I need it.
Thanks for your input, it’s always appreciated by all. If we ever get that SurvivalBlog reunion organized, it needs to have a feature called, “Tunnel Rabbit, This is Your Life!” I’m sure it would be the hit of the reunion. 🙂
St. Funo-gas,
You are too kind.
The inverter in your link is a 150 watt version that could a better choice in terms of efficiency for charging a fewer number of Boafeng radios. My guess it could comfortably charge 10 Boafengs at the same time. My choice was a 300 watt version at a similar price point.
It pays to build your PV or any small electricaly system to be as efficent as possible. Correctly sizing the devices for the power source is actually critical. For example, my old Honda generators can produce only 400 watt continuously. It would power a common and less expensive battery charger that delivers at a maximum of 20 amps at 14.7 volts. It’s small size is the more efficient choice than a 2000 watt generator, as a small 400AH deep cycle battery bank can only accept 20 amps without overheating and possible damage. In general always choose a device that will be operating closer to is rated maximum service capacity. Unfortunately that rating is not the unit’s advertised rating that is usually advertise as higher that what is can actually sustain during prolonged use. The manufacturer should have that information included in the user’s manual it provides.
The Baofeng radio charging station should handle a modified sine wave. Both of the broken links went to the same inverter. Try this link.
https://www.amazon.com/BESTEK-300W-Power-Inverter-Adapter/dp/B004MDXS0U/ref=psdc_2230642011_t1_B01H2U9DE4
For the sake of redundancy, if I could afford it, I would rather have two 150 watt inverters, than one 300 watt inverters. A second inverter is not only a back up, but can also be use at times when more power is needed. These small inverters are not built for long term use, and are known not to last indefinitely. It would be best to operate these below the manufactures maximum output. Excessive heat is usually the cause of early failure. Buying several is a sensible way to go. I would also consider a good step down transformer that would not only be more electrically efficient, but also might be more robust.
For the more adventurous, I’ll be using this little gadget to supply 10vdc directly to a bank of the Boafeng chargers, eliminating two power wasting devices such is an inverter and the 8 transformers that are supplied with the Boafeng charging bases. This will handle up to 8 Boafengs, and simplify the charging station in the ‘ham shack’. It can also step down the voltage directly off a 24 or 12 volt PV panel, thus eliminating the need for storage batteries and a charge controller. This a transformer that replaces four other devices that are either reduce efficiency, or is another link in the chain that could break. It is also multi purpose as it can be used to do other jobs. However I cannot speak to it’s longevity. Have multiple ways of getting the same job done.
https://www.amazon.com/gp/product/B07ZSGKTX5/ref=ppx_yo_dt_b_asin_title_o07_s01?ie=UTF8&psc=1
Small solar systems, or any small system needs to be set to be as efficient as possible. Choosing the correct size wire that does not reduce voltages delivered from PV panels or elsewhere, or faulty connections that can also reduce voltages, as well as the electronics used, are some of the considerations to be made. Using a 1000 watt inverter to charge a few Boafengs would consume more power to step up and convert 12vdc to 120VAC, and then back down to 10 vdc that the Boafeng can use, would be a waste of precious PV panel input that is reduced due to cloud cover. And then there is the sine wave issue. Best to stick with direct current if you can. This can also be done using a variable voltage step down transformer that works off the common cigarette lighter outlet. Do a search on Amazon for these if you only a few radios to charge.
The now defunct ‘Home Power’ magazine was a wealth of info on PV system design with very down-to-earth but highly detailed articles showing different systems people have built over the last 20+ years. They would generally include an excellent system diagram, and component cost breakdown too. If you want to research how to build your own off-grid system, either small or large I strongly recommend you register to be able to log in and download from their free archives. There are also numerous articles on wind/micro-hydro/solar water heating that are often detailed to this degree.
http://www.homepower.com/
Hey Hutch, thanks for the great link. Looks like they have lots of ideas on off-grid power systems besides just solar and each issue has a question/answer section that should be very helpful. What I would have given for a creek running through my property to build a small hydro project…
Great article and great comments. 100 kWh is fantastic. Currently we are setting money aside to build a small emergency solar system to run a few essential items depending on the time of the year. Maybe even run an appliance or two off grid permanently with the ability to expand to full off grid someday. Trusting the Lord to provide what is needed when it is needed.
Hey BWL, thanks for your comment. I didn’t even bother mentioning in my electricity usage breakdown things like kitchen appliances and most small power tools since they use such tiny amounts of electricity. They can be run off a salvaged car battery and $35 inverter for a long time. I have a system to keep my plumbing from freezing which uses a 12 volt computer “muffin fan,” which uses so little electricity I’m sure I could run it for an entire winter off one car battery charge.
Once we’re in full TEOTWAWKI mode, we’ll all learn to adjust our timing so we’re awake when the sun is shining and asleep when it’s not, and timing work projects so we can run some of them directly off solar panels.
Good luck on your solar project!
To confirm the business case, my 36 panel grid-tied PV system Installed three years ago is well on the way to 7 year payback, which is a 14% return on investment (ROI), for 20-25 years. Obviously that is much better return than CDs at the bank, however the size of the investment is limited to a practical-sized PV system.
I believe 42 states are net metering, in which utility pays you same as they charge you for each kWh. In net metering state, one can simply size the system to produce the total annual demand and virtually eliminate monthly bills. Sizing the system is more complicated and critical in non net metering states, as over production decreases your ROI.
I also used microinverters, although more expensive, they simplify wiring for DIY installers.
Dynamic (motion) panel mounting systems should be avoided as they do not cost effectively increase output and are subject the mechanical failure. Panels are cheap enough that they can provide good return even when suboptimally oriented. This can be demonstrated by the calculations from
Pvwatts.nrel.gov
Lastly, panel output has improved over the last few years. My most recent panels produce more watts than older ones, and are a better value. For those considering grid tied PV, improved panel value helps offset declining federal tax credit.
Steve, lot of good advice. I hope people are taking notes. Movable panels are definitely a waste of money if you’re trying to get your investment back, and subject to failure as you pointed out. If I were doing mine over again, there’s a cheap way to have manually tiltable panels if they are on the ground and they can be turned north/south as well as E/W.
Your ROI info is also great advice for just about anyone and adds to my confusion about why more people, especially preppers, don’t have solar panels.
Another way to help fund solar panels in some areas are solar renewable energy credits. When I installed my grid-tie array I got about half of the system paid for in just a few years between the federal tax credit and the contract for the sales of the renewable energy credits.
If the PV system was practical would it need huge solar credits???
Buckeye, that’s another great point. It’s crazy not to take advantage of people and governments who want to throw money our way for setting up solar panels.
To answer OneGuys’s question, this whole article was about why a home PV system is not only practical but will more than pay for itself three times over during the 25 guaranteed years of life of the panels. It doesn’t need huge solar credits. Those are legislated by people who want to feel like they are saving the planet, and like most of government programs, they neither makes sense nor achieve their goals. So IMO, it’s crazy not to take advantage of government’s stupidity, especially when it means they’re giving me back my money which they stole in the first place. What’s not to love? We can’t put solar panels in our “hate” column just because democrats are the ones coming up with these insane, wasteful laws.
The Powerwall batteries require an internet connection or a cell connection to operate. After a short period (I think three days) without a connection the batteries will shutdown. Not a very good choice for a prep item.
Excellent article. I think it is the best I have ever read on estimating your payback time. For comparison, I have a roof-mounted, contractor-installed, grid-tied 3.8 kW system. Payback time is estimated at 8.5 years. Payback would have been much less if I could have done the labor myself as you explained correctly.
One item worth mentioning: everyone gets focused on putting the panels on the roof at the correct angle. This is wise, but NOT mandatory. My roof pitch/angle is about 15 degrees off from perfect. But in my case it was much cheaper to just buy an extra two panels than buy all the extra supports and brackets needed to tilt a dozen panels to the correct angle.
Finally, if designing for lowest payback time, be sure to check to see if your utility provider is using Time-of-Use (TOU) metering for billing. If so, consider installing some or all of your panels to catch the late afternoon westerly sun when the payback is the best. When I designed my system last year (2019) none of the installers had the software to accurately calculate this complicating factor. Hopefully they are better equipped today. For myself, I split the difference as a guesstimate. Half are focused on the south to maximize energy produced (for future battery storage), and half are focused on the afternoon sun for TOU payback. My “true up” bill at the end of 12 months was zero, so it worked as planned.
“everyone gets focused on putting the panels on the roof at the correct angle. This is wise, but NOT mandatory. My roof pitch/angle is about 15 degrees off from perfect. But in my case it was much cheaper to just buy an extra two panels than buy all the extra supports and brackets needed to tilt a dozen panels to the correct angle.”
Gadget Guy,
You really hit the nail on the head with your “focused on” comment. I’ve been trying to come up with a term to explain why I often can’t see the obvious right off the bat, and that’s the reason: I get too focused on one thing, “to complete the objective,” and fail to consider all the possibilities.
Just for fun one day I figured out the difference in panel efficiency at nigh noon on the first day of spring when the sun rays are perfectly perpendicular to the solar panels and therefore at peak capability, vs the first day of fall when they are 23½° off prime. The difference was only a 9% loss. So you are totally correct, everything doesn’t have to be exactly perfect and many issues can be resolved simply, and often more cheaply as you point out, by adding more panels.
Thanks for your input.
I have no solar. I live in a trailer in a cold state in the midwest. I have changed all of my lighting to LEDs and that has really cut down my power usage. I run two newer refrigerators and a small chest-type freezer. Plus lights in the hallway and the bathroom during the day due to a lack of windows. In the summer I run fans to cool it off. I just got my electric bill for September and it was $66 . $43 for electricity and $23 for taxes. I used 469 kW this month. I heat and cook with propane. I was shocked to find that my bill was for $43 in electricity and $23 in taxes !
Fuel for a generator would cost more than that to provide the same power. Learning to live with minimal power consumption can set one free of the encumbrances.
I’m just a little old broken down man living in the woods in a small cabin of sorts. My big power hog is this computer. Once the net is down, I have little need of it, or grid power. I conserve my resources by using a small amount of grid power. Refrigeration is the next biggest part of that expense. In the winter the electric fridge is shut down and will switch to a propane fridge be for the summer, but only if the grid is down, or if electricity becomes expensive in some way. I will not take the mark or give into the system just so I can have an electric ‘refer’ ! In fact, one can learn how to live without a fridge. I’ve done so for years. It is hard to give up modern conveniences, but I have for the most part. I’ll cook on propane in the summer, but on a wood stove in the winter. I really do not need propane. The need to generate off grid power, be it PV panels or a wood gas fired 5 hp motor that turns an alternator, is mostly to power electronics that improve security. Yet, we can also learn how to do so without batteries.
Finding ways now to cut expenses and dependence on ‘civilization’ means one is not forced to generate a big pay check and allows us to live in the sticks, or “hinterboonies”. I can live comfortably on next to nothing, literally. Currently half of my $3,000 per annum income goes into prepping. I receive a check from no source. When civilization collapses, I will not need much of an income and can barter with things and skills for the little bit of gasoline and a few other consumables. I do so now… Those who believe they are stuck in the big cities are dependent upon modern conveniences, and will not, or cannot now head for the hills and safety.
Living without electricity and modern conveniences is easy to do, but a change in mind set is necessary. Being free from the encumbrances of a wicked society means one is free to pursue their God given liberties.
Are you taking notes everyone?? 🙂
Even when I was in elementary school crouching in the hallways during nuclear bomb drills, and Y2K, and reading about EMP attacks in One Second After, I never thought TEOTWAWKI was a remote possibility. But that was then and this is now. Picture a bearded, too-frugal-to-buy-razor-blades Tunnel Rabbit standing on the mount, with his thrift-store flowing robes, his home-whittled staff, and the ten prepping commandments in his other arm… and don’t ignore what he’s saying like all the Israelites did with the things written on the stone tablets in Moses’ day.
Just my ¼¢
Nathan, those taxes are probably not actually taxes but your meter fee. For many people, the meter fee is higher than their electricity usage each month. That meter fee goes to pay for maintenance and salaries, but in actually, it just subsidizes the Big Guys, which bugs the heck out of me since I belong to a co-op. If we paid for that maintenance the same way we pay for road maintenance (a tax per gallon of fuel), there’s be no meter fee but a tax per kilowatt. In my area that works out to a mere fraction of a cent. Having a meter fee is like having the little old granny who drives her ’69 lightweight Volkswagon bug 1,000 miles per year pay the same yearly amount for road maintenance, say $500, as the long-haul trucker who drives 350 days of the year, has a heavy truck which tears up the roads more, and puts on 100,000+ miles. It’s just plain highway robbery for all us little guys, but no one aid life was fair. In my area, literally 99% of people are driving the Volkswagen and less than 5 customers (the hospital being the biggest) are driving the 18-wheeler, yet we all pay the same for maintenance and salaries. Give me a break.
St. Funogas! Well written and wonderfully informative! You’ve given us a lot to consider in our planning for energy independence — and we thank you! Although we live in a heavily forested area, we have a couple of ideas we believe would work well. Ideas and follow up projects are definitely in development!
Hey T of A, sounds great! Good luck with your projects. We’ve been singing your praises here all week, but I’ll have to fill you in on Saturday. 🙂
2003, we built our concept of an ExpeditionVehicle on a 1997 Ford CF8000 commercial truck.
In one week, we converted it while selling everything, then hit the road!
After many thousands of miles of full-time live-aboard and minimizing our needs, we installed PV as an experiment… ‘can we thrive without it?’, ‘how much of a liability is it?’, that sort of thing.
Our system uses six 305-Watt panels for a total of 1,830-Watts.
These feed six 105ah AGMs.
(We are waiting for the lithium battery industry to mature.)
For redundancy and portability, we use several 750-Watt inverters.
We can pump fresh clean drinking water from any source using our filters / RO system of five-gallon tanks.
(We looked at 275-gallon IBC totes, then realized we couldn’t clean them to the standards of somebody in the restaurant business for a decade.
Our five-gallon tanks isolate any contamination, are easier to move, easier to share… and easier to abandon.)
We occasionally property-sit for folks in a stand-still house, but instantly long for our TinyHomeOnWheels, three paces across by seven paces long.
*****
We have acquaintances in stand-still houses.
Some are single individuals in a couple thousand square feet of ‘living space’, although it often looks like an extremely-expensive mini-storage for unused junk.
Last week, one acquaintance acquired a us$3,100 leather recliner.
Compared to the us$4,500 we paid for our TinyHomeOnWheels, does that seem extravagant?
Hey Marge, I really enjoyed your comments and thanks for the solar info.
“Some are single individuals in a couple thousand square feet of ‘living space’, although it often looks like an extremely-expensive mini-storage for unused junk.”
Amen, amen, and amen.
In my poorer county, there are tons of homes that are under 600 square feet. They are older homes and have probably never had a mortgages on them. There are also some newer small homes built by people who finally get it. A mortgageless property is a kind of freedom that you just can’t understand until you’re in that position. Sounds like you’ve arrived!
Small houses are much easier to buy, heat, cool, and defend than larger houses and helps keep us from buying junk that we have no room for.
This article has got me thinking- I looked at my electric bill and saw that my electricity cast $43 but the TAXES on it cost me $23 ! So that means that for every dollar in reduced electricity that I ise will actually save me $1.53 . And since my $43 bill was my LOWEST of the year, and my highest was in January when I used 1400 kW, (using an infared heater in the back bedroom when it was darn cold), I am motivated to check out and install some solar power. Thanks Fun-o-gas ! By the way, where did you get your name ? I don’t think there is a Saint Funogas in the religious world.
Hey Nathan, I hope you can get set up with some solar panels.
You’re correct, there is no St. Funogas in the religious world. But when there wasn’t a saint to fit my needs, I had to get creative! St. Funogas is the patron saint of those who are trying to learn to keep their traps shut and their opinions to themselves. Some days he does a great job, other days not so much, as many have noticed! 🙂
Great article! You caused me to look at my electric bill to see my usage. I average somewhere around 450kwh/month. And I thought I was very conservative with power. I bet it’s that electric water heater! Electricity is so incredibly cheap where I live in Idaho compared to other states I’ve lived in that it’s delightful if it ever hits $100/mo. Although with the new wood burning stove, I suspect my winter electric bills won’t be that high. I get it that solar is important if the grid goes down and stays down. Thanks for the good discussion here. It helped me think things through.
Hi SarahSue, glad you enjoyed the article. At 450 kWh per month, you’re still less than half of what the average household uses. 🙂 And you’re probably right, your water heater is most likely the biggest culprit.
If you want to have some fun seeing how low you can go, try operating your water heater manually from the breaker switch in your main breaker panel. It will be a double breaker. This doesn’t work with propane because propane heaters heat from the bottom up, electric from the top down. Try the five-minute thing I mentioned. Turn it on for just five minutes per day right before you take a shower. If five minutes isn’t enough, play around until you find out the right number of minutes. If there are two or more people in the house, they can turn it on for five minutes when their turn comes.
One thing that wastes hot water is when it’s left in the lines on its way to the kitchen and bathroom, then cools down. So I only use hot water from the water heater for showers. For dishes, I have a one-gallon black plastic protein powder jar which I set on my deck in the morning. By afternoon, the water is 120°F and by the time I add some cold water, it’s more than enough to wash dishes. On cloudy days, I heat up a quart of water in the microwave for dishes which is way cheaper than using the water heater. Clothes all get washed in cold water. If we can get out of the habit of turning the hot water on multiple times throughout the day, we’ll save money from all that hot water that comes out of the heater and then just cools in the line when we turn the faucet off.
If you ever need to replace your water heater, a 20-gallon tank is cheaper to run and more than sufficient for most households, but for whatever reason, 30-gallon tanks are the standard these days. They were always 20 back in the good old days.
Have fun with it and see how low you can go!
Fun! Thank you for the ideas.
Sol-Ark offers EMP hardened systems. I have installed their 8k system and am very happy with it. Growing it as I can, but have never looked back. I consider it an investment in my family’s well being, even if the payback never manifests.
Hi Dwight, I wish more people felt like you do.
I totally agree that payback is irrelevant for anyone who is a prepper or striving for self-sufficiency. The point I was trying get across with this article is the same one I try to get across to non-prepper family members: you’re going to spend the money ANYWAY for food, non-perishables, electricity, etc, so why not spend it up front so you can rest easier? As you can guess, it generally falls on deaf ears.
Thanks for putting this article out there. I’m close to pulling the trigger on installing a solar system at my homestead. Initially, I was going to do a DIY battery bank with Lifepo4 cells from China for small electronics. But now, in discerning the times and hearing rumblings from the dark overlords of grid outages and possibly cyber attacks, I decided to go all in. I’m looking to around a 7.8kWh setup with 9kWh battery backup. I might upsize a bit as I only want to do this once.
I also have a 12kWh standby generator, but that was always bought for shorter term outages. Ice storms, high winds, etc. You know, the normal power outages most of us grew up with. But normal is no more and I know a generator is not a long term solution. Even if you have nat gas or propane, if there is a major event, those services almost certainly will not be available.
Main reason is preparedness and belief that times in the future will be darker, both in a figure and literally. It is a huge investment and to pay, I will be bleeding a chunk of my “retirement” savings. I think projects like this will be even harder to pull off in the future if current trends continue or worsen. I also want to garner some of the tax savings before they are phased out.
I know there will be electricity savings as well and ROI, but as Dwight and St. Funogas noted, I’m mainly doing for preparedness.
For those who cannot afford to put in a big system, consider either DIY (look at Basen on Alibaba for good 280ah Lifepo4 cells. See Will Prowse on YT for vids) or a standalone solar generator (Titan or Bluetti). For cooking, if you can’t cook outside, but a standalone electric hotplate.