People love that using photovoltaic (PV) solar power can save money on energy bills, but very often they're just as interested in how solar panels can help the earth.

Solar is a form of renewable energy, which means it can't run out. As long as there's sunlight, there will be solar power. There are several other types of renewable energy, like wind, bioenergy, geothermal, and hydroelectric. And there are several varieties of solar power. The most common type is PV solar, which uses solar cells to convert sunlight to energy. PV is the country's fastest-growing type of energy, renewable or otherwise.

Renewable types of energy are often called "alternative" or "clean" energy because they're an alternative to traditional polluting fossil fuels like oil, coal, and natural gas. Renewable forms of energy aren't 100 percent clean though. For instance, there are environmental impacts in the production of wind turbines or solar panels. But they are far, far smaller than the impacts of burning oil, coal, and gas.

That's what makes solar and other renewables so important. They're the only way we can scale back major forms of pollution. About 65 percent of total electricity generation is created by fossil fuels. That makes electric power a huge source of carbon, one of the main gases causing climate change.

In fact, electric power plants that burn fossil fuels (and some geothermal power plants) produce about 33 percent of total U.S. energy-related carbon pollution. Just one home heated by natural gas – the cleanest of the fossil fuels – throws thousands of pounds of carbon in the air annually. Meanwhile, a Connecticut study found that one home switching from fossil fuels to solar power had the same emissions impact as planting 150 trees every year.

Solar energy and other renewables can't completely replace fossil fuels yet, but using them more often would drastically cut the amount of carbon in the air. Adopting PV solar more widely would not only reduce the threat from climate change, it could cut down on pollution-related illnesses like asthma, emphysema, and lung cancer and help with acid rain. It would also reduce pollution-related stress on plants and animals.