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GM enabling solar powered electric car charging with smart grid API's in Volt

GM and TimberRock are developing support for an integrated solar power system, with grid energy storage and electric car charging, enabling smart grid goodness.


Electric cars are often pictured in front of wind turbines or solar panels, because we want clean fuel for our clean cars. GM's OnStar division just announced a partnership with TimberRock that could make this more of a reality, directly tying solar panels, grid energy storage systems, and electric car charging.

It is a fact that most electricity comes from burning fossil fuels, and it therefore leaves the electric car open to the "coal powered car" moniker some like to toss around. But if you can clearly tie a renewable clean energy source, like solar power, directly to charging an electric car, it will be absolutely clear the fuel for that car will be 100% clean. In addition there's the opportunity to earn revenue by selling any excess solar power to the grid, or performing smart grid services with a co-located grid energy storage system.

OnStar first announced in February the availability of programming API's and other access to the Chevy Volt to support developing Smart Grid solutions for the Volt. The API's give software developers the ability to integrate the Volt or other electric cars (like the Chevy Spark EV) with Smart Grid technologies. “At OnStar, we believe that innovation is fostered best through openness and transparency,” said Nick Pudar, OnStar vice president of planning and business development. “The benefit of the approach we’re putting forth here is market-driven development of applications to best suit the needs of our customers.”

Those capabilities include:- Demand response – Allows an electric car to, while charging, respond to Demand Response signals from the Grid to ramp the charge rate up or down; Time-of-Use (TOU) rates – OnStar can receive dynamic TOU pricing from utilities and notify Volt owners of the rate plan offers via email. Charging data – OnStar also sends and receives EV data that helps utility providers without having to interface with the vehicle’s electric vehicle supply equipment. Aggregated services – This solution allows electric service providers to manage the charging of participating vehicles in a given geographic area, with customer consent. This includes the ability to control charging on a large amount of EVs simultaneously.

TimberRock is looking to monitor the output of its solar charging stations, how much stored energy is available and when it can sell energy back to the grid to help meet peak demand. OnStar has given TimberRock access to this solution so that it can start, stop and modulate the amount of charge going to a particular Volt in coordination with energy need.

“The future of electric vehicle charging will be a marriage of renewable energy and battery storage as we look to address the intermittency of renewable solar and wind power,” said Rob Threlkeld, General Motors’ manager of renewable energy. “This project supports GM’s goal of using all factors of the charging equation: electric vehicles, solar power, and battery storage.”

“We have given TimberRock the ability to use Demand Response to efficiently control the charging of their fleet of Volts,” said Paul Pebbles, GM global manager, Smart Grid and EV Services. “This is the first time a demonstration of Demand Response is being taken beyond lab or university studies.”