Solar Energy and the Environment

The sun is a fantastic resource for producing green electricity that doesn't contribute to global warming or harmful pollution.

Depending on the technology, which falls into one of two broad categories: photovoltaic (PV) solar cells or concentrating solar thermal plants, the potential environmental effects of solar power—land use and habitat loss, water use, and the use of hazardous materials in manufacturing—can vary significantly (CSP).

The size of the system—from modest, dispersed rooftop PV arrays to massive utility-scale PV and CSP projects—also has a big impact on how much of an impact it has on the environment.

Land Use

Larger utility-scale solar installations may cause issues about habitat loss and land degradation depending on their location. Depending on the technology, the topography of the site, and the strength of the solar resource, different amounts of land may be needed. Utility-scale PV system estimates range from 3.5 to 10 acres per megawatt, whereas CSP facility estimates range from 4 to 16.5 acres per megawatt.

There is less opportunity for solar projects to share the land with agricultural purposes than there is for wind installations. Utility-scale solar systems' effects on the environment can be reduced, nevertheless, by placing them in less desirable areas like brownfields, defunct mines, or current transmission and traffic lines. Smaller solar PV arrays, which can be installed on residential or commercial structures, also have little of an influence on land use.

Water Use

Solar photovoltaic cells don't need water to make power. Solar PV component manufacturing does, however, involve some water use, as does any manufacturing.

All thermal electric plants, including concentrated solar thermal plants (CSP), need water for cooling. The amount of water used depends on the cooling system type, location, and design of the facility.

For every megawatt-hour of power produced, wet recirculating CSP facilities with cooling towers draw between 600 and 650 gallons of water. The amount of water withdrawn from CSP facilities using once-through cooling technology is higher, but the overall amount of water used is lower (because water is not lost as steam). At CSP facilities, dry-cooling technology can save water use by almost 90%. These water reductions come with reduced efficiencies and higher expenses, though. In addition, the efficiency of dry cooling drops dramatically above 100 degrees Fahrenheit.

Due to the fact that many of the American places with the greatest solar energy potential also have the driest climates, it is crucial to carefully weigh the water trade-offs involved.