California Energy Commission Uses Power Quality Meters To Study The Impact Of Distributed Generation On The Grid

VICTORIA, Canada (February 28, 2005) The California Energy Commission (CEC) has completed a two-year study evaluating the effects of distributed generation (DG) on the California utility grid. As part of its "FOCUS-II project," the CEC had contracted engineering firm Reflective Energies to monitor power quality and voltage fluctuations at 14 generation and interconnection sites throughout the state. To help gather data from each site, Reflective Energies used a network of advanced ION® power quality monitors and software from Power Measurement (www.pwrm.com). According to Edan Prabhu of Reflective Energies, the findings of this study will help to promote an improved understanding of the DG-grid interface, "and in the long run, may help to support faster, more affordable and reliable interconnections between distributed generation assets and the California grid."

To gather the necessary data, Reflective Energies equipped each site with one ION 7600 power quality monitor on the electric generator, and another at the "point of common coupling" where the utility power lines meet the customers' power lines. These dual monitors helped to identify any changes in power quality, both when the DG was running, and when it wasn't. Each device was configured to monitor multiple energy parameters — including voltage, frequency, waveform distortion, harmonics, and flicker — and report this data to a centrally located PC workstation, where it was evaluated using ION Enterprise® energy management software. The resulting information helped determine whether power quality events were initiated by the grid or the DG asset.

According to Edan Prabhu, the ability to continually monitor and analyze real-time and logged system data at multiple locations was a key element of this study, and an important step towards understanding the interaction between the grid and the DG assets. "As more such information is gathered," Prabhu said, "the cumulative results of these studies will provide a better picture of DG-grid interface behavior, and help engineers to better understand and evaluate DG interconnections."

For more information, see the full report "DG Interconnection Monitoring: The FOCUS-II Project" on the California Energy Commission website at http://www.energy.ca.gov/pier/final_project_reports/CEC-500-2005-006.html

About Power Measurement: Power Measurement is a global provider of enterprise energy management systems for energy suppliers and consumers worldwide. The company's ION® web-ready software and intelligent energy meters help large businesses improve power quality, reduce energy costs and keep operations running enterprise-wide, 24 hours a day. For more information, visit www.pwrm.com.