Land Resource Use
Electricity generation generally requires the use of land resources (e.g., for mining and extraction of fuel, and for siting the electricity generating facilities themselves). The reasons that land is used and the specific environmental impacts of land use vary from technology to technology, as described below.
The extraction of natural gas and the construction of natural gas power plants can destroy natural habitat for animals and plants. Possible land resource impacts include erosion, loss of soil productivity, and landslides.
Soil at coal-fired power plant sites can become contaminated with various pollutants from the coal and take a long time to recover, even after the power plant closes down. Coal mining and processing also have environmental impacts on land. Surface mining disturbs larger areas than underground mining.
The construction of large oil-fired power plants can destroy habitats for animals and plants. Waste products from refining and from power plants (such as wastewater sludge and residues) can cause land contamination if not properly disposed. In addition, when oil spills occur on land, soils are degraded.
The construction of nuclear power plants can destroy natural habitat for animals and plants or contaminate local land with toxic by-products. For example, the storage of radioactive waste may preclude any future re-use of these contaminated lands.
Municipal Solid Waste
MSW power plants, much like fossil fuel power plants, require land for equipment and fuel storage. The non-hazardous ash residue from the burning of MSW is typically deposited in landfills.
The construction of hydropower plants can alter sizable portions of land when dams are constructed and lakes are created, flooding land that may have once served as wildlife habitat, farmland, and scenic retreats. Hydroelectric dams can cause erosion along the riverbed upstream and downstream, which can further disturb wildlife ecosystems and fish populations.
Non-Hydroelectric Renewable Energy
Photovoltaic systems require a negligible amount of land area because they are typically placed on existing structures. In contrast, solar-thermal technologies may require a significant amount of land, depending upon the specific solar-thermal technology used. Solar energy installations do not usually damage the land they occupy, but they prevent it from being used for other purposes. In addition, photovoltaic systems can negatively affect wildlife habitat because of the amount of land area the technology requires.
Geothermal power plants typically require the use of less land than fossil fuel power plants. However, if water is not re-injected into the ground after use to maintain pressure underground, it may cause sinking of land at the surface.
Generating electricity from biomass can affect land resources in different ways. Biomass power plants, much like fossil fuel power plants, require large areas of land for equipment and fuel storage. If these biomass plants burn a waste source such as construction wood waste or agricultural waste, they can provide a benefit by freeing areas of land that might otherwise have been used for landfills or waste piles. Biomass grown for fuel purposes requires large areas of land and, over time, can deplete the soil of nutrients. Fuel crops must be managed so that they stabilize the soil, reduce erosion, provide wildlife habitat, and serve recreational purposes.
Burning landfill gas to produce electricity has little impact on land resources. While the equipment used to burn the landfill gas and generate electricity does require space, it can be located on land already occupied by the existing landfill, thus avoiding any additional use of land.
Wind turbines generally require the use of land, although they may also be sited offshore. Land around wind turbines can be used for other purposes, such as the grazing of cattle or farming.
When wind turbines are removed from land, there are no solid wastes or fuel residues left behind. However, large wind farms pose aesthetic concerns and wind turbines that are improperly installed or landscaped may create soil erosion problems. Wind farms can also have noise impacts, depending on the number of wind turbines on the farm. New blade designs are being used to reduce the amount of noise. Bird and bat mortality has been an issue at some wind farms. Improvements to wind turbine technologies and turbine siting have helped mitigate bird mortality. Research on impacts to birds and bats is available at the American Wind Energy Association website.1