Hydropower Energy Information Page
What is Hydropower Energy?
Hydropower energy, also known as hydroelectric energy is a renewable energy obtained by capturing the power of moving water. This is one of the greener forms of power generation because it involves use of a fuel that is not consumed in the process of creating energy. Water naturally cycles from land to sea and back to land again. Harnessing the power of water as it flows from our lakes and rivers back into the ocean allows us to obtain electricity from a system that naturally recharges itself. Hydropower is a largely untapped resource, as only approximately 3 percent of the roughly 80,000 dams in the United States are being used to generate power.
There are a few common types of hydropower energy plants in use today, the first of which are impoundment facilities. These systems feed water from a reservoir through a turbine in a dam. The water passing through the dam spins the turbine and generates electricity. The amount of water released from the dam can be regulated based on power needs as well as to control water levels in the reservoir. This type of hydropower plant can be negatively impacted in times of drought, as there may not be enough water in the reservoir to constantly run the turbines.
Diversion hydropower energy plants are less intrusive and often don't require the use of dams. Diversion plants are commonly found along rivers, where a portion of the water is diverted into the plant and used to create electricity. This type of power plant is commonly known as a run-of-river facility and can be used on rivers where reservoirs and dams aren't feasible.
Pumped storage facilities use a combination of two reservoirs. The upper reservoir feeds water into the lower reservoir in order to generate electricity. If the upper reservoir starts to run low, water is pumped back into it from the lower reservoir. While it takes some energy to pump the water back up to the upper reservoir, this can keep the electricity flowing in times of high power demand.
Hydropower energy plants can range in size from large to small. Large plants can generate upwards of 35 megawatts, while small plants can be used to power a small village or even a single home or farm.
Marine energy harnesses the power of waves, tides or even the energy created by temperature differences in the ocean. Ocean energy is a newer form of green power, and is largely untapped. It has the potential to meet a large percentage of the world's energy needs. Marine currents, such as the Gulf Stream, generate a large amount of kinetic energy and have the potential to provide large amounts of power. They are a predictable energy source, and one that can be harnessed at a small cost to the environment.