Environment Benefits of a Typical Seattle Household Solar Electric System (3.1kW)

Most of the electricity in America comes from electrical generation facilities that burn fossil fuels, such as coal and natural gas. Whenever fossil fuels are burned, some amount of pollution is released into the atmosphere. That means that every time we use a kilowatt-hour purchased from a utility company to turn on a light or appliance, a little bit of air pollution is released on our behalf. One of the benefits of solar energy is that it does not pollute, and every kWh created by your solar power system is one that does not have to be created by burning fuel.

Scientists generally agree that as a result of the combustion of fossil fuels and other human activities, atmospheric levels of carbon dioxide have increased by nearly 30% since the beginning of the industrial revolution. Carbon dioxide, along with other 'greenhouse gases', enhances the heat-trapping properties of the Earth's atmosphere. Thus, increased levels of greenhouse gases in the atmosphere are believed to be linked to an increase in global temperature.�� Global temperatures have risen by about 1 deg F since the late 19th century, and are expected to rise another 1-4.5 deg F in the next 50 years. Rising global temperature has resulted in increased rainfall and violent storms, decreased snow and ice cover, and rising sea levels. In the US, 82% of greenhouse gas emissions comes from burning fossil fuels to generate electricity and power cars. Your solar electric power system can dramatically reduce the amount of carbon dioxide released into the atmosphere.

Using electricity generated from fossil fuels and driving cars are the two personal activities that have the most significant environmental impact. You can compare the amount of pollution generated by driving a car to that prevented by using solar electricity as another measure of the environmental benefits of solar. Generating electricity from fossil fuels also releases Sulpher Oxides (SOx) and Nitrogen Oxides (NOx) into the air. SOx and NOx are primary cuases of acid rain. Acid rain causes acidification of lakes and streams and contributes to damage of trees at high elevation and many sensitive forest soils. In addition, acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues, and sculptures that are part of our nation's cultural heritage. Prior to falling to the earth, SO2 and NOx gases and their particulate matter derivatives, sulfates and nitrates, contribute to visibility degradation and harm public health.

Trees remove carbon dioxide from the atmosphere, and are one of two major CO2 'sinks' (the other is oceans) that have helped to maintain the balance of CO2 in the atmosphere throughout the course of time. Many environmentalists advocate tree planting as a way to offset CO2 emissions into the atmosphere. Using solar electricity can be equated to planting trees in terms of atmospheric CO2 reductions.

Data sources:�� Emmisions data: US Environmental Protection Agency E-GRID 2000;�� Electricity mix and energy content:�� US DOE Energy Information Adminsistration;�� Car miles and tree data:�� US EPA, Green Mountain Power.