Hydropower is the process of harnessing energy from water. Dams are the most common example of hydropower, and the largest producers of this type of electricity are China, Brazil and Canada. As of 2016, this power source accounted for 71% of the world's renewable energy supply.
Hydropower currently makes up 7% of total U.S. energy production, providing more power than wind or solar. While it's a renewable source, it's not without impact. The U.S. does not currently use most of its dams for hydroelectricity, and experts have criticized them in recent years due to their environmental and social impact. However, new technologies are improving how these plants operate, substantially reducing their impact on the surrounding ecosystem, specifically fish and other aquatic life.
In addition to committing to other sustainable resources, there are increasingly new opportunities for the U.S. to advance hydroelectric energy production, primarily through retrofitting old plants. Innovations in renewable technology have been an integral part of discussions, as many U.S. states make promises to transition to more eco-friendly techniques.
The Pros of Hydroelectric Energy
Just like wind and solar technologies, hydropower has crucial pros and cons to consider. It's essential to weigh the advantages against the negative impact on the surrounding ecosystem. Impact also varies greatly depending on the type of system and scale of the project. For example, in-stream turbine technology has less of an effect than conventional dams.
Hydropower is a carbon-free energy system. In comparison, coal has a carbon content of 78% and releases about 204.3 pounds of the gas per million Btu when burned.
Hydropower provides a domestic source of energy, creating autonomy in local communities and reducing the need to rely on external or imported resources, such as oil.
Hydropower provides reliable and consistent energy, often referred to as it's baseload power. This feature gives this energy source an advantage over wind and solar since their supply is weather-dependent. Hydropower can also store energy, offering providers control over the excess.
The Cons of Hydroelectric Energy
While this power source has significant advantages, you should also consider the drawbacks.
Hydroelectric plants disrupt and alter the ecosystem around them. One of the main criticisms is the impact on aquatic life, primarily fish migration and biodiversity. These issues are crucial considerations considering that dam construction can come with an irreversible effect.
Large-scale dams can damage local communities. Depending on the size of the project and the surrounding environment, the construction of hydroelectric dams can cause populations to be forcibly removed and alter the quality of drinking water downstream.
The Future of Hydropower
Today, workers remove more U.S. dams than build new ones. The key to promoting hydropower as a reliable and sustainable energy source is to innovate the technologies behind the infrastructure. By improving the conventional methods of producing this power and retrofitting the current infrastructure, the U.S. can tap into a powerful resource.
Innovative technology within hydroelectric plants could potentially reduce greenhouse gas emissions by more than 5 billion metric tons. The next step will focus on new, smaller units that better adapt to the environment.
In-stream turbine technology provides an alternative to conventional dams. Similar to historic grain mills, this system harnesses hydrokinetic energy without dramatically altering the natural flow of water. The primary benefits of in-stream turbine systems include being less ecologically disruptive, more conducive to healthy aquatic life and less impactful on the surrounding ecology. One model, the Alden turbine, focuses on fish passages, or hydraulic structures that do not impede migration.
Hydropower is an underutilized technology when it comes to finding sustainable energy alternatives. The potential is expansive, and the benefits of new systems provide a reliable alternative to wind and solar options. With the innovation taking place within the industry, the opportunity to expand in the U.S. is significant.
Emily Folk is passionate about environmental sustainability and more of her work can be found on her site, Conservation Folks, or follow her on Twitter for her latest updates.