Two buildings in the Commonwealth of Pennsylvania’s state capital, Harrisburg, have been improved to achieve an expected 30 percent energy reduction throughout the combined 750,000 square feet (69675 m 2) of the buildings. The project, carried out by Buffalo Grove, Ill.-based Siemens Building Technologies Inc. and Pennsylvania’s Department of General Services, implemented photovoltaic energy systems. The Commonwealth will save the equivalent of nearly $800,000 in energy costs during the first year and that figure will escalate by approximately 5 percent per year thereafter.   Total program energy savings estimates are expected reduce equivalent energy expenses some $15 million over the life of the contract. According to DGS, net energy cost savings to the taxpayers are in excess of $2 million.