Appliances and good habits can lower bills
On a Btu basis, electricity is the most expensive form of residential energy in the U.S. Yet we use more of it — roughly 4.5 trillion Btu per year — than any other fuel except natural gas. An average household consumes 920 kilowatt-hours of power a month to feed a growing list of appliances and electronic devices and in the process spends just under $100 a month. While few households could do without electricity, most could find ways to reduce consumption.
Using less electricity has the obvious benefit of lowering monthly power bills. And because burning coal generates about half of the nation’s electrical supply, conservation also reduces the amount of carbon dioxide and other pollutants released into the atmosphere.
In residential construction, conservation techniques have nothing to do with the network of cables and switches we install. Those costs are essentially fixed no matter how much electricity is eventually used. Cutting consumption requires efficient appliances, a conservation-minded household, and common sense.
In most cases, electricity generated on site with a photovoltaic or wind system will cost significantly more than grid power. However, some homeowners are willing to pay more for renewable energy because of its environmental advantages. Others feel more secure knowing that some of their energy is generated close to home. Amortized as part of a mortgage, photovoltaic or wind equipment can generate a positive cash flow, especially in states with generous renewable energy incentives or tax credits.
Photovoltaic (PV) modules produce electricity directly from sunlight. The silicon used to manufacture photovoltaic cells is plentiful, but is expensive to refine to a useful state. It costs between $30,000 and $60,000 to install a photovoltaic array large enough to meet the energy needs of a small house, so most residential PV systems meet only a…