Hydropower Overview

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Hydropower Overview

Hydropower — also known as hydroelectric power, is a renewable energy source that accounts for more than 7% of electricity generation in the United States. Hydropower is one of the largest and oldest renewable energy sources and allows us to use water flow in rivers and streams to create energy. 

Want to learn more about hydropower in the United States? Keep reading to learn how hydropower works, how it’s used, its costs, and more.

How hydropower works

Hydropower is created by converting the force of flowing water into energy. Hydropower generation relies on the water cycle, which has three steps:

1. Solar energy heats water, causing it to evaporate
2. Evaporated water falls as precipitation
3. Precipitation collects in flowing water, empties into oceans and lakes, and continues the cycle

Humans can create hydropower for energy using hydroelectric power plants, usually located on or near a water source — one of the largest plants is the Hoover Dam. At these power plants, water flows through pipes and pushes against blades, turning them and spinning a generator to create electricity.

Hydropower for your home

Hydropower is one of several renewable energy sources used to power homes in the United States. Hydropower is created at hydroelectric power plants then fed into the electrical grid that powers homes and businesses.

In addition to the hydropower added to the electrical grid to power homes, it’s also possible to utilize hydropower independently. Microhydropower refers to a form of renewable energy generated by individuals or businesses with small hydropower systems. Individuals or businesses with rural property and running water can use a microhydropower system to create electricity right on their own property and use it to power their home or business.

Cost of hydropower

As with any energy source, it’s essential to discuss the costs of converting it into usable electricity. Compared to other renewable and nonrenewable power sources, hydropower is a relatively affordable form of electricity generation. In fact, it offers the lowest cost compared to all primary fossil fuel and renewable energy sources.

Installing a residential hydropower system is also more affordable than turning to other forms of renewable energy. According to the National Hydropower Association, a microhydropower system has an average price tag between $4,000 and $6,000.

Where is hydropower thriving?

Hydropower makes up 7.3% of all electricity generation in the United States and more than one-third of renewable energy generation. And while it remains a popular source of U.S. energy generation, it’s more prevalent in some areas than others. 

Some states — primarily Idaho, Washington, and Oregon — rely heavily on hydropower for electricity, thanks to their many running water sources. Residents of those states are rewarded with lower average energy bills than the rest of the country.

Here are the top states for hydropower energy:

FAQs about hydropower

Is hydropower a renewable resource?

Yes, hydropower is a renewable resource. Because hydropower generation relies on the water cycle, which constantly repeats, it’s one of the largest renewable energy sources.

What percentage of US electricity comes from hydropower?

In 2020, hydropower made up “7.3% of total U.S. utility-scale electricity generation and 37% of total utility-scale renewable electricity generation” in the U.S., according to the EIA. 

What state produces the most hydropower?

States like Idaho, Washington, and Oregon produce the most hydropower in the nation, and residents in those states generally have lower-than-average energy bills.

How many hydropower plants are in the U.S.?

There are roughly 1,450 conventional and 40 pumped-storage hydropower plants in the United States. The oldest operating plant around today began operation in 1891.

Learn more about alternative energy sources

• Green Energy
• Solar
• Biomass
• Geothermal
• Wind Energy

Updated: 11/5/2021