Friday, September 19, 2008

Off-grid Systems and Off-grid People

“To acquire knowledge, one must study; but to acquire wisdom, one must observe”. Marilyn vos Savant

Some off-grid systems and the people who use them:

I have an off-grid photovoltaic (PV) system, but since I’m connected to the electrical grid I can’t honestly say that I know what off-grid living is like. My system powers some loads on a daily basis, and serves as an emergency backup system, but I rely on the power grid for most of my everyday electricity needs. The closest I’ve come to real off-grid living has been during those times when my grid power failed. To understand what off-grid living is really like it’s helpful to peek into the lives of those who actually live off-grid on a full-time basis.

An off-grid lifestyle can range from primitive to luxurious, depending upon the size of the system. While some are happy with a minimalist lifestyle, it’s common to find others who after attempting to live off-grid, have become disillusioned upon realizing just how much work is involved. Some give up, and others enlarge their systems until they achieve an acceptable comfort level. On the other end of the spectrum are off-gridders who want all of the conveniences that their well-connected counterparts in the city enjoy. This group includes the well-to-do who choose to live in an area where utility services are unavailable. Most off-gridders, I suppose, fall somewhere in-between primitive and luxurious.

With these things in mind, let’s look into the lives of some off-grid people and their systems:

#1. Can you guess which country has the most residential solar PV systems installed? It’s Kenya. PV systems are replacing kerosene lamps in remote villages, greatly improving the quality of life of the residents. Typically, these small systems are only able to provide a few hours of light each night, but the importance of the elimination of fire hazards and indoor air quality improvements cannot be overstated. Because children can study longer into the evening with the extra light, these small systems also have an educational benefit.

#2. Here in the United States, Ward’s solar PV system was built for less than $700.00. It provides all of the electrical needs of this bachelor in his remote cabin, including lights, TV, VCR, and a boombox. Ward uses a wood-burning stove for heat, and a propane refrigerator. He has no indoor plumbing. His system includes a 75-watt solar panel, four batteries, a charge controller, and a 350-watt inverter.

#3. It would be a disservice to Karen to limit this discussion to her PV system. Karen transformed a 5-acre site in the Mojave desert to a comfortable homestead. Among her accomplishments Karen installed a septic system and a 4000 gallon water tank. She renovated an old cabin, including a passive solar system of her own design. Karen uses a wood stove for heat, and propane for cooking and refrigeration. And yes, she put in a solar PV system. Her system includes 400-watts of PV, 880ah of battery capacity, a charge controller, and a 3500-watt inverter. A system of this size can be built for less than $3000.00. Because Karen’s system is larger than Wards, she can do much more. Her capabilities include pumping water, running a vacuum cleaner, and using kitchen appliances.

Although Ward and Karen may be satisfied with what they have, a typical family would probably struggle to get by with such limitations. Some might opt for the prepackaged 2000 watt off-grid PV system described below. The cost of the entire system, including batteries and wiring, is in the neighborhood of $20,000.00. A system of this size will allow the use of a washer and dryer, and almost any electrical device imaginable. In spite of the size of this system, the average family of four may experience shortages of electricity from time to time. Energy efficient construction, efficient heating and cooling systems and efficient appliances will help, but some homeowners will opt for a generator to make up for periods of extended cloud cover.

System Specifications:

PV: 2000 Watts
Batteries: 6000ah
Pre-Wired Power Center with 4,400 Watts 120/240VAC

Need even more electricity? Obviously you can have as much as your budget and space will allow. Your decision to live off-grid means that you’ll have to maintain your own power systems, but it’s really not that difficult. You’ll have sophisticated equipment that automates some of the maintenance tasks and alerts you to small problems before they become big ones. You’ll know the status of your batteries, and the amount of stored power at a glance. If you choose to install a generator as a backup, it can be set to start up automatically in the event that it’s needed.

Ward and Karen may be thought of as being on the fringe of society now, but that notion will change someday. Declining fossil fuels and an increased awareness of the harm we’re doing to our environment will someday make a change to renewable technologies a necessity, not just a good idea. Folks like Ward and Karen will be typical, not the exception. We’ll all be better off when that happens.

For more off-grid systems and people, click on this link:

Here’s another site that showcases off-grid systems and people:


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