Assessing the Emissions Impacts of Demand Response Programs Due to Diesel Backup Generation in California

EPA Grant Number: FP917341
Title: Assessing the Emissions Impacts of Demand Response Programs Due to Diesel Backup Generation in California
Investigators: Huffaker, Erich
Institution: University of California - Berkeley , Ernest Orlando Lawrence Berkeley National Lab
EPA Project Officer: Michaud, Jayne
Project Period: September 1, 2010 through August 31, 2013
Project Amount: $111,000
RFA: STAR Graduate Fellowships (2011) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Emerging Environmental Approaches and Challenges: Information Science


Many have attested to the value of Demand Response (DR) in maintaining grid stability and reducing peak demand. However, not much research has looked at its environmental impacts. Specifically, what are the emissions impacts in California of the backup diesel generators (BUGs) that many DR participants rely on to meet their curtailment obligations?


The basic approach will be to utilize recently available data on when BUGs run within the State of California to assess cumulative emissions impacts. First, the study aims to obtain and format the run-time logs, which detail the specific usage patterns of BUGs in California. Then, the study will identify which of these BUG owners also are participants in DR programs. The hours of BUG usage will be cross-referenced against the schedule of events for various DR programs, providing a target number of hours that BUGs are used for DR. Then, the study can assess the emissions rates of PM, SOx, NOx and any other relevant criteria pollutants for each of these generators. The next step will be to create a simple spreadsheet tool that policy makers may use to input raw data on BUG usage. The output of the tool will be emissions rates that air quality modelers can utilize to determine specific local effects.

Expected Results:

There is a dearth of research examining the specific impacts of BUGs in demand response. However, one previous study in 2005 attempted to quantify the impacts using modeling tools, finding that the impacts of such usage were significant and negative overall. It is likely that this study underestimated the cumulative effects that the current study’s results will uncover. As a result, the study expects to find that the usage of these generators poses a significant threat to the environment and air quality.

Potential to Further Environmental / Human Health Protection

Long-term exposure to PM has a well-acknowledged history of correlation with lung cancer and cardiovascular disease. PM emissions drive up the overall risk factor of pollution in an area. Concentrations of BUGs are highest in urban areas, so their emissions have a proportionally higher impact per capita. In addition, BUG pollution from DR occurs on event days that are typically the hottest, smoggiest days of the year. In sum, this study will aim to give insight in PM and other emissions that occur in the worst possible places, at the worst possible times.

Supplemental Keywords:

BUGs Demand Response, emissions impacts demand response, diesel generators demand response, demand response air quality, diesel generators, backup generators, particulate matter (PM)

Progress and Final Reports:

  • 2011
  • 2012
  • Final