Published on January 29th, 2007 | by Philip Proefrock
How reasonable is it to try to generate your own power? You want to take that big, green step, but there are a lot of unknowns. Is it hard to do? Does it take a lot of equipment? Will the systems last? What is the best system to use for your location?
I can't give you simple, easy answers to most of these questions, since there are too many factors, and it's not a one-size-fits-all kind of question. However, there is one question I can answer: Is it worth considering a renewable generating system? The answer to that is 'yes.'
I attended a local presentation last week that addressed many of these questions. The topic was a small solar installation that was done at a local food co-op. They received a $6000 grant, which they used to install a small demonstration system. This system does not provide all the power they use, but it does offset some of the electicity which they would otherwise be buying from the grid. The program was just a quick overview of the system they had installed, not a comprehensive explanation about how to install your own photovoltaic system. The important point covered with this presentation was that it is not that difficult to do a renewable power system installation. Most of the work for this project was done by people with just some basic handyman experience. Because it was a commercial installation, they had to have an electrician oversee the electrical work, but, other than that, they did it all themselves. Installing a renewable power system is more than a weekend project. But it doesn't necessarily require specialty experts.
Most states are now net metering states . (In Canada, there are even possibilities for better-than-net metering.) In my home state (Michigan) this is a relatively recent development, and not many people are aware of it yet. Net metering programs very from state to state, but in general, if you are producing more power than you are using, the utility company allows you to put the excess onto the grid and your power meter runs backwards (sometimes literally). In Michigan, you can overproduce and carry it over as a net credit on the following month's bill, as long as you are not over-producing on an annual basis. (If you do that, the utility gets to collect the overage.)
Some key points to consider:
- Skip the batteries. Batteries are expensive. They are full of toxic materials. They require frequent maintenance. If you are connected to the grid, the grid (and net metering) is your backup and your offset. Only cabins and other locations that are far off the grid should worry about allthe added headaches of batteries for power storage. This makes for a much simpler system.
- Don't worry about making 100% of your power. If you are offsetting 25% of your total power consumption with locally produced renewable energy, you are still making a significant contribution.
- Consider an expandable system. The co-op installed 4 panels with the grant they received, but the system they bought has the capacity for 6 panels. As panel prices come down, they will be able to expand the system at a lower cost-per-watt and increase the power they are producing.
Because you are producing your power locally, you are also not suffering the system and transmission losses you face when buying power from the grid. Roughly 2/3 of the energy used in power generation is lost through heat and inefficiencies of the generating plants and transmission losses. (U.S. Department of Energy) So for 100 kWh used, as measured on your home meter, more than 300 kWh of energy was used to make and deliver that electricity. When you are producing that power locally, you are offsetting more than just the power you are using. Local production effectively triples your carbon offsets.
Generating your own power is still an expensive proposition. With an electric power cost of 10 cents per kilowatt/hour (kWh), a solar system (in Michigan) that gets an average of 4 productive hours per day still won't pay back its costs over a 30 year lifespan (though sunnier states will do much better). However, that assumes that electric power is not going to get more expensive over those 30 years (and that's highly unlikely). And, since you are going to be buying electricity anyhow, if you instead put that money into a renewable generating system, then you are just paying a premium of the difference between what you would have been spending on the power anyhow and the cost of the system.
Photo: Solar panels at the Ypsilanti Food Co-op