Consumer backup generators (BUGS) offer a large untapped resource on the consumer side of the meter at many commercial and industrial customer facilities in the United States and can play a significant role in flattening the utility load profile to the economic and environmental benefit of utilities, consumers, and society.

This is among the conclusions of a recent report from the U.S. National Energy Technology Laboratory (NETL) in its smart grid implementation strategy series.

Properly integrated, BUGS, which are used for either emergency or standby applications, can have an environmental as well as economic benefit because they are well distributed, quick to startup and shutdown, close to the point of consumption, and more responsive than large, traditional power sources, says the report.

The low asset utilization of standby and emergency applications represents 170 GW of untapped capacity in the U.S., amounting to about 22 percent of the peak and 36 percent of the average load in 2009, and suggesting they could potentially serve larger loads, certainly at peak. A Portland General Electric (PGE) demonstration showed a significantly lower conversion cost per kW as well as a 30 percent or more reduction cost per kW over simple cycle gas turbine costs. The key to increasing the capacity factor of BUGS is interconnecting them to the grid and using them to serve larger loads.

The generators within the emergency power are predominately diesel fueled reciprocal engines. Preliminary calculations indicate there is also a reduction in CO2 and other emissions with these, compared to gas turbine peaking units. For example, engaging half of the BUGS for peak reduction during 200 hours a year could result in a reduction in CO2 emissions of more than 935,000 tons a year compared to natural gas peaking units.

The smart grid as described in the Modern Grid Strategy envisions the accommodation of all generation resources and optimizes the efficiency of the available assets (see Smart grid – the sytems view). Enabling BUGS as a peak resource is one option that builds on the enablement provided by the smart grid.

The full report can be viewed here:
Backup Generators (BUGS): The Next Smart Grid Peak Resource

Related Smart Grid Implementation Strategy report:
Energy Storage – A Key Enabler of the Smart Grid