(Continued from Part 1. This concludes the article.)
POWERING UP & MORE TO LEARN
Don’t expect step-by-step instructions. I found all the needed information but chronological steps for start-up or shut-down are not readily available. However, there is plenty of online info where people figured out the best steps. I powered up my inverter with battery power first, then went through the entire menu. Go slow, though it’s pretty easy. A couple of battery voltage settings from the battery manufacturer were the only deviations. Then I turned the solar panel input on and waited for the screen to recognize battery & solar power. I then turned my inverter on from standby to ON. I turned the main breaker in my subpanel on and was powering my house!
I left my utility feed OFF for the time being as I wanted to see how the system would perform. This was now October 2021, in the middle part of the US, so sunlight was waning significantly. I already had a significant shadow of the bottom 20% of my solar panels. I was later told by an expert who saw a photo of my install, that because I mounted my panels vertically, long side up & down, I was limiting my energy output more than the 20% shading. My first mistake, but performance was fine through the darkest days of winter so I did not react to the advice. I feel I need to see how this works before I begin changes.
As to electrical performance, now almost 5 months out, we are so happy with our system. Switching power sources is automatic, seamless and silent. We had a storm power outage and did not know until a neighbor called to point out only I had power. I’ll have to work on that, it was so obvious.
Continuing, our electric bill is now less than half of pre-install. But, I also installed the heat pump water heater and I believe the water heater was the bulk of our usage. I turned utility power off to the system for the first 2 weeks of February 2022. Each evening our home would run on stored battery power. As soon as the sky brightened the solar took over power the house and during peak sun, charged the battery back to 100%. I discovered that even with full clouds the panels generate electricity. Just not as much.
Interestingly, with the monitoring system I have learned my home “idles” at just 400-500 watts of power needed. So that’s 2 refrigerators, a freezer, and all our lights and daily living requirements. Of course electrical usage goes up with microwave oven, dishwasher, blow dryers, vacuums, et cetera. Even with all of this usage and the system handles it perfectly. I bought a second 5,000 watt inverter, identical to my initial unit for redundancy. I feel that if something is going to fail this is it. Everything else can be worked around. I wired in this second unit and alternate using the 2 units, at least for now.I also alternate my 2 battery banks rather than using both together.
As of the end of February the shadow on my solar panels is gone for the bulk of the day now. So guessing that I will get full sun March through September at my location. At this point I just have some excess power being generated. But, not wanting grid tie restrictions and too many eyes on my system, selling back this little excess is not economically smart. My system as-is, is not compatible nor compliant with my local grid tie requirements. My son has a large commercially sold, professionally installed solar array on his home, in another state. No battery storage. He says the sale back to the utility is practically nonexistent and his electric bill is still high. Part of these facts are due to where he lives and he not adjusting the family activities to sunlight hours.
THE MANY THINGS I HAVE LEARNED
This is certainly not for everyone. Professionally done, while much more expensive, is a viable option to achieve silent, no-refueling-required backup electrical power.
I spent much more than I originally anticipated. Part of the extra cost was the second battery bank, about $2,100, and a second all-in-one inverter, $899. Even eliminating those two items I spent more than I thought I would. A good rationale at this point is the quality, life span and maintenance requirements of my system. Maintenance is limited to regularly cleaning the solar panels. But compared to several friends that have had different types and capacities of home generators installed, my cost has not exceeded any of their costs.
In total, I spent $11,217 on this system. Obviously no labor is in this figure as I did all the work. This total is very accurate down to screws, washers & labels.
To install one battery bank and one inverter with the same 10 solar panels was approximately $6,967, which is much closer to what I expected to spend originally.
The ready to connect batteries cost $3,320 and are 200ah [amp hour] and have 10,000 wh[watt hours] of capacity. The raw cells, build yourself were $2,025 and are 280ah and have 13,600 wh of capacity.
The heat pump water heater is actually a big energy saver. My personal experience in life has been that most energy-saving devices either don’t save much or any energy and/or don’t perform well. Having researched this water heater for some time and the fact that the product already has a multiyear track record, I highly recommend these units. Price is high, 50 gallon – $1,549. And this too is not for everyone. The heat pump is quiet but does make noise. The unit exhausts a very large amount of cold air. This either has to be ducted out or to a useful area. Just to point out these nuances.
As I mentioned earlier, my wife and I are very happy with this system. I am retired so this project was fairly easy. I invested about 112 manhours on this project, not including research & education. From idea to startup was 67 days, and that includes the water heater install.
Also as I said previously, the scale of size and number of solar panels to run your home is very large. I have about 4,400 watts of solar but that’s capacity, you will never get that. Maybe 70% average during daylight is one theory of what you can expect as output. Conversely, my son has 30,000 watts of solar panel capacity. That runs his home during sunlight and sells excess back to his utility. He is then on full utility at night and has no power at all during power outages. The battery provides a buffer of storage for low usage times and the place to provide extra power for you during high usage in your home.
The batteries are rated for full cycles, that is 100% fully charged to basically empty. While these lithium batteries can do this, by not going to these extremes it has been shown that they will last much longer. Example, when I was on NO utility power for a month, one battery had a drawdown of 52% [48% left] after 2 cloudy days, lots of wash, dishwasher and two extra people in our home for a week. So that was the biggest drawdown. Normally, my batteries fluctuate between 75% and 100% indicated. Technically I have settings whereas I don’t charge fully to the top. This cycling pattern will increase battery life almost indefinitely. These batteries will most likely outlast me. Again, this is not for everyone. This solved a predicament that was bothering me for some time. I can now say that the product I was looking for, an emergency generator, is obtainable and performance exceeds my expectation. This system runs my home, with no rationing or saving actions. When there is an event our plan is to shut off all accent lighting, & turn off visible power usage to outside eyes. Our home “idles” at such a low electric consumption rate that there are not many things to shut down.
Energy Conservation
This brings up a big issue with my wife and I. (Jumping on my soapbox…)People’s ability or willingness to conserve energy. Whether it’s friends or family members, our experience is that most people leave lights on, ceiling fans on, etc. Seemingly oblivious to the simple act of turning the switch off when you leave a room. We almost always find all the lights on when we wake up in the morning in other people’s homes, even our smart, successful children. Or changing your furnace filter? Rare. I could go on but my point is, for instance, I believed that everyone switched over to LED light bulbs. Boy was I wrong. And this is a big deal, especially when one leaves lights on for no reason.
Take a standard recessed can light in the USA, it’s typically a 60 or 75 watt bulb. Let’s use the 60 watt for this example, this bulb uses 60 watts of electricity all the time it is on. A 60 watt LED equivalent bulb uses 9 watts of electricity. This is a very big deal with a system such as mine. We have 24 recessed can lights in our home and when we moved in, just 2 years ago, there were 75 watt incandescent bulbs installed. That’s 1,800 watts of possible electrical load versus my LED replacements, 11 watts each totaling 264 watts. That’s a real savings of 85% I believe.
Of course, people will say that lighting in a home is generally not a large part of your overall electric usage, which is true. That’s not an excuse not to save, plus a good LED bulb will last many years. Anyway, back to my main subject. Being realistic about your actual electric needs is a main point of my plan here. I never wanted to power our electric range or our electric clothes dryer. Our AC is optional at this point to be powered by solar. To me, this appliance is too demanding on my equipment to warrant powering every day.
I hope this story of my journey helps at least one person get through the tribulations facing us all. God Bless you all.