Out of Signal Hill, ReJoule’s innovations have been sold around the world, and the company is focusing its efforts on disadvantaged communities next.
On a quiet Signal Hill street, surrounded by oil pumps and offices, a family-owned renewable energy company is slowly spreading its technology around the world.
ReJoule was founded in 2017 by siblings Steven and Zora Chung, and made its home in a Signal Hill warehouse in 2020. The company specializes in repurposing electric vehicle (EV) car batteries to store solar energy for use at night.
In the coming years, ReJoule will create solar energy storage systems for three locations across the U.S. The company wants to focus on commercial-scale solar energy in under-resourced communities instead of single-family homes.
In September, the company was awarded two separate grants from the United States Department of Energy (DOE) to produce its technology on its largest scale yet. ReJoule received a $10 million grant from the DOE over the span of seven years to build three solar grids using their original design for workforce training and housing sites in disadvantaged communities.
Zora called the grants a “huge game-changer” for the company, as it’s the biggest funding allocation they’ve received.
A Leap of Faith
The brother and sister duo started ReJoule with an idea for renewable energy, and an interest in creating their own business inspired by their upbringing.
“Our parents are small business owners and they always encouraged us to start our own business,” Zora said. “So the seed was planted at a young age.”
Zora was working in corporate finance for one of the largest companies in the United States when her brother brought the idea of his business to her. Fresh with a Master’s degree in engineering, Steven had the option of starting his own company, pursuing his Ph.D. or working for any number of defense companies. His sister pushed him in the entrepreneurial direction, and he immediately asked her to come along with him.
“He knew he needed someone who understood business and he needed someone he can trust,” Zora said, adding that it wasn’t an easy decision to leave her job to join her brother. “ … I saw the opportunity for a huge positive impact and it was in an area that I was definitely not familiar with.”
For the first three years, Steven worked on his designs to test the remaining life in used EV batteries. Zora worked to find them possible buyers and make their name in the marketplace of renewable energy.
After working out of their parent’s surplus warehouse space, ReJoule received its first round of grant funding and was able to purchase its headquarters in Signal Hill.
The two were unaware of Signal Hill’s historical, deep-rooted ties to petroleum and oil drilling, though they vaguely noticed the tens of oil pump jacks surrounding their business. Zora said the “global trend” of energy is moving towards renewable and reusable methods, accounting for the increased funding from the federal government.
Why Electric Car Batteries?
Electric car sales have grown from 0.2% in 2011 to 4.6% in 2021. S&P Global Mobility projects that electric car sales will account for about 50% of all car sales in the United States by 2030.
Most batteries need to be replaced about 10 years into their life, with 90% of their capacity still remaining, said Tobias Hecht, program manager for ReJoule.
California is in the early stages of figuring out what to do with these batteries and how to recycle them to avoid a surplus of hazardous waste. ReJoule found a solution, and it’s sitting in salvage yards and used car lots around the country.
“What we want to do is maximize the value of the batteries and let it be used as long as possible … Getting extra use out of the battery is just really important otherwise you’re wasting life left in the battery,” Hecht said.
The batteries currently being used to install solar energy storage for residential homes are produced overseas, and the Institute for Energy Research found that mining for these resources have detrimental impacts on the environment.
ReJoule is using batteries already in the country, where the supply chain will increase exponentially in the coming decades.
Dual Track Innovation
The company’s first goal was not to create solar energy storage units, but to test these batteries to decide if they can be used in the first place. This process is called “cycling,” and used to take almost 10 hours (after the 1,000-pound car battery was removed).
ReJoule’s first major accomplishment was creating technology that can successfully do the same in just 10 minutes. They’ve deployed this technology to three continents since its creation.
Now, the company is working on the next step: how to test batteries without having to remove them from the vehicle, which can be a laborious four-hour process and deemed useless if the battery has little life remaining.
Zora said the market for this technology is only growing, and they hope to help used car companies deploy the technology so they can know if an electric car they’re purchasing has sufficient battery life.
ReJoule is also hoping this will make solar energy more affordable, and thus more widespread, by drawing from an already-existing supply chain instead of ordering new batteries for projects from overseas. It currently costs around $38,000 for a single-family home to be installed with solar energy, which may explain why 90% of residential solar storage is with privately owned homes.
This creates a barrier of access for owners of apartments and affordable housing developments, which is why ReJoule is creating its first large-scale storage units for affordable housing and workforce training developments.
“Our hope is that in the future, the repurposed batteries will be a much cheaper alternative,” Hecht said. “We’re focusing on building critical infrastructure for disadvantaged communities so there’s a large benefit.”
Two of ReJoule’s solar energy storage systems will be deployed in affordable housing developments; one in Santa Fe, New Mexico and the other in Petaluma, California. The California complex holds 131 units, and ReJoule is planning on its most ambitious project yet, by allowing the site to draw from solar energy 24 hours a day, year-round.
These projects were made possible by the widespread partnerships ReJoule has made with other renewable energy companies, housing developers and electrical contracting companies.
“It will probably be the nation’s first affordable housing complex running off solar energy year-round,” Hecht said.
