One of the most important steps that you can take toward self-reliance is developing the ability to produce your own electricity. Alternatives for off-grid power include:
- Photovoltaics
- Wind Power
- Micro-Hydro Systems
Photovoltaic (“PV“) power generation systems use large panels that generate DC voltage. The most durable panels use monocrystaline solar cells in large arrays in weather-sealed panels with glass covers and metal frames. These are designed to last a lifetime with just minimal care, and do not suffer any significant degradation in output over time. They are made with outputs from 5 to 100 watts. They are easily wired in series or series-parallel arrangements to yield the desired voltage and wattage to feed to a battery bank. With plenty of competition between manufacturers, the cost per watt for PV panels has plummeted in the past decade. So PVs are the preferred method of making your own power off grid.
Amorphous solar cells with flexible plastic covers are also now available, but only recommended for tactical applications where you have to stay on the move. In general, amorphous panels are less weather resistant than traditional monocrystaline solar cells hard panels. They also will lose up to 10% of their output over the course of several years, due to UV degradation.
Wind Power systems have been used for many years. Typically they use turbine blades geared to a generator or alternator, mounted on top of a tower. Wind generators work well only at hilltop locations where you get fairly high wind speed regularly. They are relatively high maintenance, noisy, occasionally self-destruct during wind storms, and they pose safety risks for those that climb their towers to do maintenance. In general, I don’t recommend wind power systems if you live in an area with good solar exposure. If that is the case, it is usually best to simply add more PV panels to your system rather than adding the complexity of a wind generator system.
One exception to my aforementioned guidance on wind power is wind-powered water well pumping. The reliability of wind power for lifting water directly with mechanical power is an order of magnitude less complex than an a DC wind generator. .. Traditional “AeroMotor” water-pumping windmills (still manufactured) once dotted the landscape in the midwest. They only fell into disuse with the cheap electricity made by the rural electrification programs that began in the 1930s. Water pumping windmills are incredibly simple and efficient: A mechanical windmill that lifts a sucker rod up and down, operating a brass pump cylinder at the bottom of the well shaft. Aside for occasional greasing of bearing surfaces and replacing the pump cylinder leathers every ten years, they require minimal care.
Micro-Hydro systems (small, water-powered Pelton Wheel electrical generators) are great if you live on a fast moving stream or creek where you can get a permit to put in a small dam. (Simple in states like Idaho and Wyoming, but a bureaucratic nightmare in some of the more populous Nanny States.) To be efficient, you need to have enough “fall” of water, since it is that potential energy that is utilized to spin a water turbine. One of the simplest and best little turbines in the micro-hydro world is the “Lil Otto” brand, made by Bob-O Shultze. See: http://www.ibiblio.org/pub/academic/environment/alternative-energy/energy-resources/homepower-magazine/archives/15/15pg14.txt
Batteries, Charge Controllers, and Inverters
Nearly all home power systems utilize a battery bank to store energy and an inverter to convert DC power into 117 VAC. Despite recent advances in gelled and AGM battery designs, the best buy for a fixed location retreat (in terms of amp hours per dollar) is still the good old-fashioned flooded cell lead acid battery. Just be sure to get the heavy duty deep cycle variety, with threaded terminal posts. Because lead-acid batteries are very heavy and shipping costs are usually prohibitive, it is best to buy a set of deep cycle batteries locally. Just contact your local Trojan or Exide battery dealer. Be sure to include a charge controller in your system to prevent over-charging.
If you can suffice with a very frugal and austere lifestyle, you might omit the inverter and buy all 12 VDC and/or 24 VDC appliances. But in practice, this is usually too much to ask of most modern homesteaders who are accustomed to having both DC and AC tools and gadgets.
Resources on the Web:
Home Power Magazine: The best magazine on the subject. They generously provide on-line archives of some of their articles. See: http://www.homepower.com/
Ready Made Resources: Pre-packaged and custom PV systems, inverters, and back-up generators. They provide free consulting. See: http://readymaderesources.com
Backwoods Solar Electric Systems: See: http://www.backwoodssolar.com/ (I’ve known Steve Willey for about 15 years. He really knows his stuff!)
Real Goods/Jade Mountain: See: http://www.realgoods.com/
Xantrex (formerly Trace) Inverters: See: http://www.xantrex.com/