At the Applied Process Engineering Laboratory, PNNL installed a 30-kilowatt microturbine system. The small, natural gas-powered turbine can be started remotely by BPA to produce electricity for the building during times of peak electrical demand. This on-site production, called distributed generation, helps reduce stress on transmission lines by supplying some of the power for the building directly instead of pulling from the regional power grid.
The second project eases stress on the grid by allowing BPA to "shed load" or reduce the demand for power by remotely turning off air conditioning and HVAC equipment at two smaller buildings and the 200,000-sq-ft Environmental Molecular Sciences Laboratory. At EMSL, six air handlers are cycled on and off, for approximately 10 minutes at a time.
Unlike radio-controlled methods which utilities have used elsewhere, this system uses the Internet and computerized equipment to make changes without any physical action necessary at the buildings.
"Our engineers have preprogrammed a sequence of power-saving actions that take place once BPA remotely initiates load shedding," said Srinivas Katipamula, PNNL's project manager. "But ultimately, occupant safety and comfort take precedence."
Elsewhere, utilities have demonstrated load shedding and distributed generation as a way to defer building new electrical generation facilities. In the Northwest, BPA, through its Non-Wires Solutions program, is exploring ways to defer the construction of new transmission lines throughout the region. The PNNL demonstration project is part of this effort.
"We are evaluating whether we can use direct load control to shave load at peak demand times to keep prices lower for everyone," said Mike Hoffman, a BPA public utilities specialist. "It is not unusual for construction of a transmission line to cost upwards of $100 million or more." Commercial buildings are considered an untapped resource for direct load control with more than 4.7 million commercial buildings in United States. "While the PNNL demonstration project is relatively small, providing a total of just 175 to 275 kilowatts of load reduction at any given time, the potential for savings is great," said Katipamula.
The PNNL demonstration project uses features found in existing building automation controls and allows them to communicate directly through the Internet without expensive, intermediary devices. BPA can control the load through a website which provides status of the equipment and feedback on how the commands have been executed.
This project will help BPA quantify whether this type of non-wires solution will work to help reduce demand during periods of high electrical usage-typically hot summer afternoons or cold winter mornings. The project is expected to continue through the end of 2005.
The microturbine distributed generation project at the APEL facility is an ongoing collaboration with Energy Northwest, a public power agency located near Richland, which owns the building and is paying the natural gas fuel costs associated with the microturbine.