Boothbay Project Seeks Cheaper Alternative to Costly Electricity Transmission Upgrades

Jan 21, 2016

BOOTHBAY, Maine — An innovative effort to reduce the need for costly new electricity transmission lines is showing some early success here.

When Central Maine Power proposed its $1-billion-plus upgrade to its main transmission system to make it more reliable, regulators approved — but as part of the deal they also tried an experiment in Boothbay. The idea was to test whether the construction of new transmission systems serving the peninsula could be avoided by installing some local technologies that could reduce demand and also generate electricity.

And the results of that test were promising.

“We can save ratepayers a significant amount of money by adopting this approach,” says Richard Silkman of GridSolar LLC, which is running the project.

Silkman says that on the hottest days, when electricity demand peaks, air conditioners at participating Boothbay businesses can be turned off. But GridSolar still can keep workers cool with a system that uses ice banks that are frozen when electricity demand is lower.

The company, which controls these systems remotely, can fire up a diesel electricity generator or pull energy from a very big battery placed just down the road. The project included the installation of new rooftop solar arrays and high-efficiency LED lighting on the peninsula. Put all that together and you get the alternative to transmission upgrades between Newcastle and Boothbay that CMP had said were needed to ensure grid reliability on high-demand days.

The cost for the GridSolar alternative is about $9 million, the company says in a new state filing — if regulators allow it to continue another 8 years. Grid Solar says that’s just one third the 10-year cost of a new transmission line.

Ben Tettlebaum, an analyst at the Conservation Law Foundation, says the project should be continued and expanded. He adds that administrators of the New England power grid will need to be convinced that the cost of such transmission alternatives should be shared by all of the region’s electricity users.

“With the right amount of advocacy and stakeholder support I think we can see some traction there,” he says. “I think it is challenging but I don’t think it’s an impossibility.”

Public Utilities Commission staff are analyzing GridSolar’s project report and will hold hearings next month on whether the effort should be continued. After that, GridSolar could propose similar — and bigger — transmission alternatives for the midcoast region and Portland.