This may come as a surprise, but the next big development in the electricity industry is not solar. It also isn’t wind, biomass or hydropower. Instead, it involves what we do after those renewable energy sources create electricity. Unless we create a reliable battery that stores extra generation, we will waste electricity and ultimately limit the development of renewable energy technology.
Renewable energy storage is the next big technological breakthrough, and major companies are researching, developing and commercializing energy storage technology. Over the next two decades, the likes of Tesla, GE, and Lockheed Martin will invest $640 billion into this project.
Let’s talk about what energy storage technology is used for and why it has the potential to alter everything we know about electricity.
Why is Energy Storage So Important?
To answer this question, we must first talk about the electricity grid and how it works. The United States consists of three major electricity grids: the Eastern Grid, the Western Grid, and the one in which Chariot Energy currently operates, the Texas (ERCOT) Grid. While the system is massively complex, all three grids are ruled by the basic economic principle of supply and demand.
Electricity output must always equal input. In other words, however much power the Texas population needs, it gets. No exceptions. The grid operates at a frequency of 60 Hz, but if the grid is stressed because supply is less than demand, the frequency can slightly drop to compensate. If there is more electricity on the grid than people need, then the frequency can raise slightly. But when the frequency of the grid gets really low or really high, it starts to cause problems, with brownouts and blackouts chief among them.
Renewable energy sources, specifically wind and solar, present a big challenge to how the grid normally operates under fossil fuels. Solar and wind energy are considered intermittent energy sources. Because we can’t control when the sun goes down or when the wind is going to blow, they aren’t constant, so the grid can’t rely on them in times of stress. Conversely, fossil fuels can be burned anytime, but they aren’t good for the environment nor are they sustainable.
This is the problem that electricity storage aims to solve: How can we deploy electricity from clean energy sources without having to rely on unpredictable weather patterns?
6 Types of Energy Storage Available Today
Traditionally, you may think of batteries as energy storage — and you’d be right! Lithium-ion battery storage is one of the six different ways we can currently back up power. Those include:
- Pumped Hydroelectric: Not only is this form of energy storage renewable, but it also comprises 94% of all United States energy storage today. Electricity pumps water upstream, and the water is then released downward to spin turbines that generate electricity when we need it.
- Molten Salt: A highly efficient method, molten salt stores heat energy captured by concentrating solar power (CSP) plants. These plants use highly reflective mirrors to concentrate the sun’s energy to heat salt to a molten state. When energy is needed, the salts heats water to spin steam turbines to create electricity. It’s emissions-free and solar-powered.
- Batteries: These are giant versions of the metal tubes that power your calculator. But instead of providing a few volts, these batteries store electricity capable of powering thousands of homes. By the end of 2018, the U.S. had 869 MW of installed power capacity and 1,236 MWh of energy capacity.1
- Compressed Air: When there is more supply than demand for electricity, this method compresses air that can then be released when demand is greater. The compressed air is typically stored underground in depleted oil and gas reservoirs, and it’s emissions-free.
- Liquid Air: Another way of storing air for energy, electricity cools air to a liquid state during the off hours. When demand is up and supply is low, the air expands and evaporates to spin a turbine to create electricity.
- Flywheels: Flywheels store electricity using kinetic energy. Electricity spins a magnetically levitated rotor tens of thousands of times per minute in a vacuum space. This provides a nearly frictionless environment akin to space that can be reconverted back to electricity when demand is high. Because of its inefficiencies, it is the least-implemented storage technology of the six.
The Benefits of Developing Energy Storage Technology
Energy storage technology has the potential to utterly transform how we create, sell and use electricity. The U.S. Department of Energy calls renewable energy storage a “major breakthrough” in electricity distribution.
In the past, solar and wind weren’t seen as key players in meeting peak electricity demand. The solution was to either shift people’s usage to match when renewables created electricity or give us the control to use power whenever we want. With an effective energy storage infrastructure, solar and wind can and will compete with on-demand energy sources like coal and natural gas. This will only further transition us away from relying on fossil fuels and toward a sustainable, more green future.
Challenges of Energy Storage Deployment
The future does not come without challenges, though. Currently, we lack in all three of the major steps to implementation:
- Research and development
Thankfully, the Department of Energy recently announced the $150 million Energy Storage Grand Challenge in July 2020 to address all three issues. By 2030, the Department of Energy aims to create a secure, domestic supply chain that does not depend on foreign sources of “critical materials.”2 We’re guessing those critical materials include fossil fuels.
Emerging technologies like flow batteries, stacked blocks and superconducting magnetic energy storage — as well as further research, development and deployment of lithium-ion batteries — all show promising hope for a brighter, cleaner future.