Energy Information Administration – Geothermal Heat Pump Manufacturing Activities (03/17/2009): “Information in this report indicates that the 2007 total geothermal heat pump shipments surged 36 percent to 86,396 units, while capacity shipped rose 19 percent to 291,300 tons. While 2007 capacity growth was substantial, it was below growth in 2006, which was 53 percent. Total rated capacity of geothermal heat pumps shipped in 2006 was 245,603 tons, compared to 160,402 tons in 2005.”