Recycling is complicated, potentially hazardous and often inefficient, however. A recent study by the European Federation for Transport and Environment found that capacity across the continent is 10 times below where it needs to be in 2030, with almost half of planned facilities at risk.
The energy system, meanwhile, has some challenges of its own. Transitioning from grids built around large, centralised power stations to a cleaner but more fragmented system makes distribution and control more difficult.
“Electricity is moving in different directions from different sources, and also obviously the load profile is changing,” says Matthew Lumsden. The CEO and founder of Newcastle firm Connected Energy is tackling the automotive and energy sector challenges simultaneously, using ‘second-life’ EV batteries in stationary storage. From a first proof of concept in 2013, the company is now planning utility-scale deployments to capture surplus green electricity when it is generated and dispatch it when needed.
“The batteries used in electric vehicles typically need to be replaced before they're fully degraded, and they have a lot of usable capacity left in them that is accessible before they're recycled,” says Lumsden, who is speaking at IMechE’s upcoming Energy Storage 2025 conference.
“Effectively what we do is a ‘handshake’ with some of the battery OEMs, some of the automotive OEMs, and some of the people who are financing and owning and operating the big fleets, and say: ‘If we take those after you finish with them on the road and we put them into stationary energy storage, then we can do a lower-impact stationary energy storage project.’”
Matthew Lumsden, CEO and founder of Connected Energy
Aiming for capacities from 10 megawatt (MW) to 100MW and more, Connected Energy hopes its M-STOR sites could “maximise green power utilisation”. The company website references a Lancaster University study that found a 450-tonne carbon dioxide-equivalent saving for each megawatt-hour of storage using second-life batteries, compared with systems using new lithium-ion batteries.
By monetising second-life batteries, Lumsden also hopes that leasing companies and OEMs can introduce an additional revenue stream, helping to reduce the lifetime cost of a battery and therefore the overall cost of a vehicle.
Adapting such heavily used components – warranties for EV batteries typically last eight years or 100,000 miles, although predictions suggest they could last up to 20 years – brings some inherent challenges.
“Our batteries are partially degraded, so the energy density is lower than you would have on the first-life system,” says Lumsden. “It's not suited to every application. But where you have some more space, then it's a viable alternative to new systems.”
While the use of degraded packs might raise some safety concerns, the CEO says these are avoided thanks to automotive battery cells being a “much higher quality” than those found in other battery energy storage systems (BESS). “The safety systems that are in the battery pack are designed to protect you and your family while you're travelling down the motorway,” he points out.
Batteries also typically fail in a “bath curve” distribution, he adds, either at the start of their lives or after years of use. “Once they've settled down, they function for a long time.” Connected Energy also has its own safety monitoring and systems.
The company’s planned large-scale BESS will look very similar to systems using first-life batteries, Lumsden says. Shipping containers will hold rows of reused packs, with each container holding one type of battery. Different containers could then be used alongside each other to maximise reliability and efficiency.
The first such system is planned to be installed later this year, with further projects planned in the UK and France, and more announcements coming early next year. Lumsden, who has worked in both renewable energy consenting and the EV industry, expects to see a “massive ramp-up” in available batteries between now and 2030 as the market continues to mature.
Environmental impact
The company founder will also moderate a roundtable at the IMechE event on the environmental impact of grid-scale energy storage, which varies depending on the type of technology used. This can also include first-life batteries, pumped hydro, compressed air and thermal energy storage.
“Fundamentally, storage is enabling the proliferation of renewable generation and obviously that's gradually decarbonising the grid,” he says. “But then you've got a less positive side, which is around the environmental impact… clearly the market is trying to move away from being reliant on very finite and difficult-to-access resources.”
The carbon cost of projects is also becoming increasingly important, he adds, alongside the thorny issue of supply chain vulnerability due to resource availability and geopolitical turmoil.
“As we get into security of supply issues and as ultra-long storage is required, then it becomes even more pressing,” he says. “As those dynamics change, when you can see the profitability coming out of it, it will drive innovation in the market even more.”
Energy Storage 2025: Delivering Grid-Scale Storage and Stability will take place at Manchester Metropolitan University on 29 April. Find out more and book now on the event page.
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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.