A MBTA HSP46 testing. Photo by Pi.1415926535 at wikipedia.
MBTA needed new equipment, the HSP46 is MBTA's solution. In 2010 the MBTA board approved the purchase of new locomotives. These locomotives are powered by GE GEVO12 power plants from GE, equipped with a static inverter for head end power, and capable of meeting the EPA Tier 3 standards. AC-traction systems, prime movers, head end power equipment, and computer systems are supplied by GE, while MPI is supplying the brake systems, air systems, and cooling systems. The locomotives have started arriving(as of August 2013). In 2011, the MBTA released images of new paint which will be applied to the authority's HSP46 fleet. It was chosen by the general public in an online survey. In 2012, the MBTA Board voted to approve the first option for 7 locomotives, bringing the order total to 27 units (1200-1226). In April 2013, the MBTA Board approved the purchase of the remaining 13 option locomotives; the current order total is 40 units (1200-1239). These units will enable MBTA to retire 40 of its oldest locomotives. However, they have not been retired. And instead of the HSP46's being numbered 1200-1239, they were renumbered to 2000-2039, for unknown reasons.