Philadelphia's Subway Trains Are Becoming Rolling Power Factories

The transportation sector accounts for nearly half of United State's total energy consumption. With fuel prices continually climbing, those energy costs are cutting into already-strained state budgets. To combat its carbon footprint, the South East Pennsylvania Transit Authority (SEPTA) has outfitted its light-rail… » 5/11/12 2:40pm 5/11/12 2:40pm