Hydroelectric energy is a mainstay in modern power grids. It combines the energy output of coal or gas-fired power plants with the carbon output of a wind turbine. Sounds perfect, right?
Hydropower is an awesome resource—if you have space and capital to build one. Hydropower, as efficient and carbon neutral as it is, has issues, especially when it comes to costs. Read below to learn how hydro energy works, how efficient it is, and its advantages and disadvantages.
How Do We Produce Energy with Hydro?
Energy is a quality found in many things around the world. Gas and goal produce energy by combustion, meaning a reaction occurs that heats water into steam, which then turns a turbine.
Hydro energy, in contrast, does not need a combustion reaction to create energy. Instead, hydro energy plants harness the energy from the downward pressure gravity puts on water. As water flows down a river, it is full of kinetic energy.
Humans can harness kinetic hydro energy with dams or run-of-the-river turbines. Dams halt the flow of water, directing it into turbines that spin as the water passes through them. Run-of-the-river plants are just turbines in the water, with little or no need for a dam holding back any water.
Both of these produce energy by allowing the water to run through turbines. These turbines work in the same way steam ones do, except there’s no combustion. As the turbines spin, they power a generator that sends power to the grid system.
Uses of Hydroelectric Energy Today
The uses of hydroelectric energy vary widely depending on where you are. Washington state alone produces more than a quarter of all hydro energy in the USA. The most common uses of hydroelectric energy today are:
- Residential or commercial electricity
- Industrial electricity
- Back-up power for grid failures/overconsumption
Hydropower is also a way to control water levels. If a hydropower plant has a dam, it can choose to operate at a higher capacity, meaning more water will go through the turbines. By doing that, dam technicians can control the water level in the reservoir.
The Efficiency of Hydroelectric Power
According to the Canadian Hydropower Association, hydropower converts 90% of available energy into electricity. That makes hydro the most efficient power generation source we have at our disposal!
The newest models of natural gas-fired power plants can only convert 60% of available energy into usable electricity. By having a more efficient energy source, electricity providers can offer better rates with a more reliable power source.
Advantages and Disadvantages of Hydroelectric Energy
Hydropower is not without its faults, though. Here are the most common advantages and disadvantages of hydroelectric energy:
Advantages of Hydroelectric Energy
Of the dozens of advantages of hydroelectricity energy, three stand-out as significant. First, hydropower doesn’t produce any CO2 byproducts, which means it’s a clean, renewable energy source.
The second advantage of hydropower is its flexibility. If energy demand rises or lowers, hydro energy plants can increase or reduce to flow of water to account for any changes.
The final primary advantage of hydroelectricity energy is its stability. There won’t be jumps in price due to demand or limited supply. Water always has the potential to move through the dam turbines, so there’s no need for price gouging.
Disadvantages of Hydroelectric Energy
There are two primary disadvantages of hydroelectric energy—cost and environmental damage. Cost overruns plague most dam projects because of their size. That means there’s a potential for a lot more upfront costs when a dam project begins compared to a coal or gas plant.
Dams also have significant impacts on their environments. Although they don’t produce CO2, they still disrupt local ecosystems. Fish who live or spawn in their streams, flooded land, and forcing residents to move are all negative environmental impacts that hydro energy can potentially cause.