VOLTTRON is an innovative open source software platform that helps users rapidly develop and deploy new control solutions for a myriad of applications in buildings, renewable energy systems and electricity grid systems. Developed by Pacific Northwest National Laboratory with funding from the Department of Energy, VOLTTRON can be downloaded from the not-for-profit Eclipse Foundation that will steward it as an open source software platform. As part of this move, PNNL has joined the Eclipse Foundation, a global organization with more than 275 members.