Officials at the T are exploring renewable energy options and have plans to install solar panels at two sites in order to save an estimated $250,000 on electricity costs annually.

According to T spokesman Joe Pesaturo, the T is putting two parcels out to bid under one contract — Readville Yard 5 in Dedham and the Wonderland Parking Garage.

The T hopes that construction begins in the fall of 2012.

The winning bidder will be given access to the sites to build and maintain the solar arrays and in exchange, the MBTA will buy the electricity, according to officials.

The contract with the T would last 20 years.

Once chosen, the contractor will have 12 months to start generating electricity, according to the proposal.

Last year the MassDOT board approved a procurement mandating that 20 percent of the T’s purchased electricity come from certified renewable energy sources.

Next stop, Somerville?

MBTA officials said if all goes well with these two parcels, they may consider putting out a bid to place solar panels on the T’s Somerville facility. The 8-acre rooftop houses the commuter rail maintenance facility.

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