Water Resource Use

Various Energy Resources

Electricity generation generally involves the consumption of water resources (e.g., for steam production and cooling, equipment cleaning, and other purposes). The water consumption and the environmental impacts of water use vary from technology to technology, as described below.

Natural Gas

The burning of natural gas in combustion turbines requires very little water. However, natural gas-fired boiler and combined cycle systems do require water for cooling purposes. When power plants remove water from a lake or river, fish and other aquatic life can be killed, affecting animals and people who depend on these aquatic resources.

Coal

Large quantities of water are frequently needed to remove impurities from coal at the mine. In addition, coal-fired power plants use large quantities of water for producing steam and for cooling. When coal-fired power plants remove water from a lake or river, fish and other aquatic life can be affected, as well as animals and people who depend on these aquatic resources.

Oil

Oil-fired power plants use large quantities of water for steam production and cooling. When oil-fired power plants remove water from a lake or river, fish and other aquatic life can be killed, which affects those animals and people who depend on these aquatic resources.

In addition, the drilling of oil requires water to remove obstructions from the well, and refineries require water in the various processes used to refine crude oil into usable fuel.

Nuclear Energy

Nuclear power plants use large quantities of water for steam production and for cooling. When nuclear power plants remove water from a lake or river for steam production and cooling, fish and other aquatic life can be affected.

Municipal Solid Waste

Power plants that burn MSW are normally smaller than fossil fuel power plants but typically require a similar amount of water per unit of electricity generated. When water is removed from a lake or river, fish and other aquatic life can be killed, affecting those animals and people who depend on these resources.

Hydroelectricity

Hydropower often requires the use of dams, which can greatly affect the flow of rivers, altering ecosystems and affecting the wildlife and people who depend on those waters.

Often, water at the bottom of the lake created by a dam is inhospitable to fish because it is much colder and oxygen-poor compared with water at the top. When this colder, oxygen-poor water is released into the river, it can kill fish living downstream that are accustomed to warmer, oxygen-rich water.

In addition, some dams withhold water and then release it all at once, causing the river downstream to suddenly flood. This action can disrupt plant and wildlife habitats and affect drinking water supplies.

Non-Hydroelectric Renewable Energy

Solar

Photovoltaic systems do not require the use of any water to create electricity. Solar-thermal technologies may tap local water resources if the liquid that is being heated to create steam is water. In this case, the water can be re-used after it has been condensed from steam back into water.

Geothermal

Geothermal power plants usually re-inject the hot water that they remove from the ground back into wells. However, a small amount of water used by geothermal plants in the process of creating electricity may evaporate and therefore not be returned to the ground. Also, for those geothermal plants that rely on hot, dry rocks for energy, water from local resources is needed to extract the energy from the dry rocks.

Biomass

Biomass power plants require the use of water, because the boilers burning the biomass need water for steam production and for cooling. If this water is used over and over again, the amount of water needed is reduced. Whenever any type of power plant removes water from a lake or river, fish and other aquatic life can be killed, which then affects those animals and people that depend on these aquatic resources.

Landfill Gas

Engines or combustion turbines that burn landfill gas to produce energy typically require negligible amounts of water.

Wind

Wind turbines in areas with little rainfall may require the use of a small amount of water. If rainfall is not sufficient to keep the turbine blades clean, water is used to clean dirt and insects off the blades so that turbine performance is not reduced.