With more plug-in electric vehicles on the road today than ever, automakers are working to solve an impending issue: what to do with used lithium-ion batteries.

Once the batteries are no longer suitable to power vehicles, automakers must recycle or repurpose them.

Now, through a partnership with The Mobility House, the Renault Nissan Alliance is planning to use them in a 100-megawatt power storage plant in Europe.

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The energy-storage facility would give used lithium-ion batteries from the automakers' electric cars a second life for many years into the future.

Reuters reports the plant will be big enough to power 120,000 homes, roughly equaling the output of of one natural-gas or coal-powered utility station.

It may also be used to cover electricity consumption during peak demands. 

Longer-range Renault Zoe electric car, introduced at 2016 Paris Motor Show

Longer-range Renault Zoe electric car, introduced at 2016 Paris Motor Show

The batteries do not generate electricity; instead, they charge—from any generation source, including renewable solar and wind—during times of excess supply and feed electricity back into the grid when needed.

A Renault spokesperson confirmed the automaker is working with The Mobility House but did not specifically confirm the energy storage plant.

"We're working with The Mobility House on several programs including a major energy storage project that is currently still in the study phase," the automaker said.

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Sources told Reuters that Germany or the Netherlands are the top two candidates for the energy storage plant due to their high energy prices.

Like experimental energy-storage facilities in California and elsewhere, the plant's most important role could be to help smooth out solar and wind's unpredictability.

Not only does the project give the automaker a place to repurpose used battery packs, but it can earn its operators money competing with traditional utility companies as it sells the power back to the grid.

Longer-range Renault Zoe electric car, introduced at 2016 Paris Motor Show

Longer-range Renault Zoe electric car, introduced at 2016 Paris Motor Show

One analyst foresees automakers adding energy-supply components to their businesses in future.

"What will end up happening is that BMW and Daimler will ... become utilities themselves," said Gerard Reid, founder of Alexa Capital LLP.

In the meantime, Renault continues selling Europe' most popular electric car, the Zoe.

CHECK OUT: 2017 Renault Zoe electric car: larger battery doubles range

That car has experienced a surge in popularity with the introduction of a larger 40-kilowatt-hour battery pack this year.

Under the French system of battery leasing (separate from purchase or lease of the car itself), lessees are able to swap out their earlier, lower-capacity packs for the new, longer-range battery, giving even older Zoes up to 200 miles of range.

In the United States, Nissan is gearing up to introduce the 2018 Leaf, which will sport more conventional design and likely greater range.


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