Solar energy delivers environmental benefits
Many homeowners, businesses, and non-profits go solar because they are focused on minimizing environmental issues like climate change and health problems related to carbon emissions. According to the U.S. Environmental Protection Agency, the average household emits approximately 20 metric tons of carbon pollution each year. By installing a solar power system, a typical two-person household reduces their carbon emissions by three to four tons annually.
The U.S. Green Building Council reports that buildings contribute 39 percent of all carbon emissions in the United States. Going solar helps to decrease these effects. While every home, business or non-profit that adopts solar power makes a dent in our pollution levels, the cumulative effect of property owners adopting solar across the country is what really makes a lasting impact.
Replacing fossil fuel power plants with renewable energy sources, including solar, wind, hydropower and geothermal power, would reduce diverse types of pollution. The magnitude of difference in pollution between fossil and some renewable energy options is stunning. For example, we found that the entire process of manufacturing, setting up and operating photovoltaic panels causes less pollution than only delivering fuel to a coal-fired power plant when mining is included.
What about the environmental footprint of actually making renewable energy systems?
Photovoltaics (PV) comes out very well in our analysis. Today, the production of PV cells uses much less energy than previously. The carbon emissions per unit of PV electricity is one-tenth or less of even the most efficient natural gas power plants. Human health problems, such as respiratory disease from particulate matter exposure, are around one-tenth of those of modern coal-fired power plants with advanced pollution control equipment. Similar conclusions hold for water and soil pollution on ecosystems, we found.
But solar panels require much more space to generate the same amount of power as fossil fuel or nuclear power generators. Shouldn’t cover huge areas with solar panels be a problem? Not necessarily. The amount of land needed to generate a kilowatt-hour from PV is comparable to that of coal power when the land associated with mining coal is accounted for. And about half of the PV installations in our future scenario in 2050 could be placed on rooftops.
Producing PV panels does require various metals, many of which are produced only in limited locations. Some of those metals are highly toxic. Waste treatment and recycling, which we did not include in o
How, exactly, does solar reduce greenhouse gas emissions? The electricity that solar panels produce is completely emissions free. When you use renewable solar energy to meet your energy needs, you reduce the demand for electricity from your utility. As a result, your utility plant emits less carbon when producing the power needed to meet customer demand. Depending on the resources that your utility uses to produce energy — many are still reliant fossil fuels like coal—the impact of your decision to go solar could be very significant.