Amtrak will put 70 new electric trains into service for the Northeast corridor, which can feed 100% of the energy they generate from braking back into the grid. The savings are estimated at $300 million over 20 years

Amtrak is the latest train line that’s converting to new generation locomotives, those that send energy back to the grid while substantially increasing their own efficiency.

70 new electric locomotives, Amtrak Cities Sprinters, will service the Northeast corridor starting this fall. They’ll be added gradually until they are all in service in 2016, replacing locomotives that have operating for 25-35 years.