Our energy choices have direct impacts on our health, environment, and economy. No energy technology is perfect, but science helps us assess the options and make smarter decisions. With our members’ support, UCS experts analyze today’s energy technologies to find balanced, realistic solutions for our energy needs.
In this section, you’ll learn more about the sources of energy available today—how they work, how viable they are, and the advantages and drawbacks of each.
Renewable Energy: Unlimited Resources. Nearly Zero Pollution.
Renewable energy generates electricity from sustainable sources like wind and solar power with little or no pollution or global warming emissions. An array of technology is used to harness this natural energy. Turbines harvest the wind. Solar panels collect the sun’s energy. Geothermal plants tap into heat below the Earth’s surface.
Learn more about renewable energy technologies:
How wind power works
How solar energy works
How geothermal energy works
More renewable energy technologies
What are the benefits and impacts of renewable energy?
Coal and Other Fossil Fuels: A Dirty Source of Energy
Fossil fuels—coal, natural gas, and oil—produce most of our electricity but come with significant and harmful consequences. They produce the vast majority of global warming emissions. They release toxic chemicals that pollute our air and water. And they have adverse, and costly, effects on public health.
Coal is the worst offender, a dirty, carbon-intensive fuel source that pollutes the air, fouls our environment, and single-handedly produces more than a quarter of U.S. global warming emissions. More on coal and other fossil fuels.
Fossil fuels produce power through combustion, generating heat that is then converted to electricity.
Learn more about fossil fuel technology:
How coal works
How natural gas works
How oil works
Nuclear Power: Risky Energy
Nuclear power generates electricity from the heat produced by splitting atoms—usually uranium—through a process called nuclear fission. Nuclear power plants produce no air pollution or global warming emissions when they operate but can cause catastrophic damage to human health and the environment in the event of a meltdown or other disaster, as evidenced by the 2011 Fukushima disaster in Japan. More on nuclear power.
Energy and Water Use
The energy choices we make have direct implications for our water supplies. Conventional power plants place heavy demands on our water resources—coal power consumes the most, but natural gas and nuclear power also require significant amounts.
Some renewable energy sources—such as biofuels and concentrating solar power—also require water, while other renewable technologies like wind turbines and solar panels essentially use no water at all.
As the Earth heats up in response to global warming, some already dry regions will receive even less moisture, further exacerbating the challenge. Learn more about energy and water use.
Learn More About Our Energy Choices