The European GreenDataNet project, involving Nissan and Eaton, proposed the idea last year - but has not yet told us of a live test. The idea of using electric car batteries in data centers has been suggested previously. The 2016 Volt will introduce a 31 percent increase in driving range, presumably due in part to changes to the battery. The project has been done using the current generation of Chevy Volt batteries. GM had previously demonstrated repurposed Volt batteries as an alternative power source for home use, collaborating with Duke Energy in a demonstration that showed how the repackaged batteries could be used for storing power when the rates are low and providing power when the demand and prices went up. There are currently 130 applications running in the data center, with 15 older data centers already consolidated and shut down. The data center is one of two that GM is using to consolidate from 23 previously existing facilities. The energy stored will be used in the administration building. The five battery unit has a capacity of 85.5 kWh, which is a good match for the energy that can be provided by solar and wind sources. They have active thermal control and each one contains 288 prismatic cells giving it the ability to provide 17.1 kWh of stored energy. The lithium-ion (Li-ion) batteries are 5.5 foot long, t-shaped, and weigh 435 lb (198 kg). GM is testing the idea with five retired Chevrolet Volt batteries which provide power to the data center facility. However, it is often pointed out that renewable sources are often intermittent, and so will make more sense when coupled with local storage. That is enough to power the office building and lights in a parking lot.
Milford already has renewable energy input, from a 74kW solar array and a pair of 2 kW wind turbines.