Kristina Hamachi LaCommare

Cost of power interruptions to electricity consumers in the United States (US)

The massive electric power blackout in the northeastern U.S. and Canada on August 14-15, 2003 catalyzed discussions about modernizing the U.S. electricity grid. Industry sources suggested that investments of

Power and Frequency Control as it Relates to Wind-Powered Generation

50 to

Tracking the Reliability of the U.S. Electric Power System: An Assessment of Publicly Available Information Reported to State Public Utility Commissions

100 billion would be needed. This work seeks to better understand an important piece of information that has been missing from these discussions: What do power interruptions and fluctuations in power quality (power-quality events) cost electricity consumers? We developed a bottom-up approach for assessing the cost to U.S. electricity consumers of power interruptions and power-quality events (referred to collectively as reliability events ). The approach can be used to help assess the potential benefits of investments in improving the reliability of the grid. We developed a new estimate based on publicly available information, and assessed how uncertainties in these data affect this estimate using sensitivity analysis.

Evaluation Framework and Tools for Distributed Energy Resources

This report is a part of an investigation of the ability of the U.S. power system to accommodate large scale additions of wind generation. The objectives of this report are to describe principles by which large multi-area power systems are controlled and to anticipate how the introduction of large amounts of wind power production might require control protocols to be changed. The operation of a power system is described in terms of primary and secondary control actions. Primary control is fast, autonomous, and provides the first-line corrective action in disturbances; secondary control takes place on a follow-up time scale and manages the deployment of resources to ensure reliable and economic operation. This report anticipates that the present fundamental primary and secondary control protocols will be satisfactory as wind power provides an increasing fraction of the total production, provided that appropriate attention is paid to the timing of primary control response, to short term wind forecasting, and to management of reserves for control action.

Review of the Recent Frequency Performance of the Eastern, Western and ERCOT Interconnections

Large blackouts, such as the August 14-15, 2003 blackout in the northeasternUnited States and Canada, focus attention on the importance of reliable electric service. As public and private efforts are undertaken to improve reliability and prevent power interruptions, it is appropriate to assess their effectiveness. Measures of reliability, such as the frequency and duration of power interruptions, have been reported by electric utilities to state public utility commissions for many years. This study examines current state and utility practices for collecting and reporting electricity reliability information and discusses challenges that arise in assessing reliability because of differences among these practices. The study is based primarily on reliability information for 2006 reported by 123 utilities to 37 state public utility commissions.

Understanding Bulk Power Reliability: The Importance of Good Data and a Critical Review of Existing Sources

LBNL-52079 ERNEST ORLANDO LAWRENCE B E R K E L E Y NATIONAL LABORATORY Evaluation Framework and Tools for Distributed Energy Resources Etan Z. Gumerman, Ranjit R. Bharvirkar, Kristina Hamachi LaCommare, and Chris Marnay Lawrence Berkeley National Laboratory 1 Cyclotron Road., MS90-4000 Berkeley, California 94720 Environmental Energy Technologies Division February 2003 Download from: http://eetd.lbl.gov/ea/EMS/EMS_pubs.html#RE This work described in this paper was funded by the Assistant Secretary of Energy Efficiency and Renewable Energy, Office of Building Technologies of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098.

Distributed generation capabilities of the national energy modeling system

The reliable operation of an electric power system depends on careful management of the balance between generation and load to ensure that system frequency is maintained within narrow bounds around a scheduled value. Yet, maintaining frequency at the scheduled value is challenging because the load served is continuously changing, and occasionally, events such as the sudden loss of a large generation plant or large amount of load, cause frequency to deviate abruptly. This report reviews the recent history of frequency performance for all three U.S. interconnections: Eastern, Western, and the Electric Reliability Council of Texas (ERCOT). The review is based on data collected by the North American Electric Reliability Corporation (NERC). The review focuses on frequency response, which measures the performance of the interconnections immediately following sudden, large imbalances between load and generation. Trends in frequency response are presented and preliminary efforts are made to relate frequency response to other aspects of frequency performance and to examine aspects of the methods used to calculate frequency response.

Investigation of residential central air conditioning load shapes in NEMS

Bulk power system reliability is of critical importance to the electricity sector. Complete and accurate information on events affecting the bulk power system is essential for assessing trends and efforts to maintain or improve reliability. Yet, current sources of this information were not designed with these uses in mind. They were designed, instead, to support real-time emergency notification to industry and government first-responders. This paper reviews information currently collected by both industry and government sources for this purpose and assesses factors that might affect their usefulness in supporting the academic literature that has relied upon them to draw conclusions about the reliability of the US electric power system.

A quantitative assessment of utility reporting practices for reporting electric power distribution events

This report describes Berkeley Labs exploration of how the National Energy Modeling System (NEMS) models distributed generation (DG) and presents possible approaches for improving how DG is modeled. The on-site electric generation capability has been available since the AEO2000 version of NEMS. Berkeley Lab has previously completed research on distributed energy resources (DER) adoption at individual sites and has developed a DER Customer Adoption Model called DER-CAM. Given interest in this area, Berkeley Lab set out to understand how NEMS models small-scale on-site generation to assess how adequately DG is treated in NEMS, and to propose improvements or alternatives. The goal is to determine how well NEMS models the factors influencing DG adoption and to consider alternatives to the current approach. Most small-scale DG adoption takes place in the residential and commercial modules of NEMS. Investment in DG ultimately offsets purchases of electricity, which also eliminates the losses associated with transmission and distribution (TD enhancing the cash flow analysis but incorporating aspects of DG economics that are not currently represented, e.g. complex tariffs; and using an external geographic information system (GIS) driven analysis that can better and more intuitively identify niche markets.

A Model of U.S. Commercial Distributed Generation Adoption

This memo explains what Berkeley Lab has learned about how the residential central air-conditioning (CAC) end use is represented in the National Energy Modeling System (NEMS). NEMS is an energy model maintained by the Energy Information Administration (EIA) that is routinely used in analysis of energy efficiency standards for residential appliances. As part of analyzing utility and environmental impacts related to the federal rulemaking for residential CAC, lower-than-expected peak utility results prompted Berkeley Lab to investigate the input load shapes that characterize the peaky CAC end use and the submodule that treats load demand response. Investigations enabled a through understanding of the methodology by which hourly load profiles are input to the model and how the model is structured to respond to peak demand. Notably, it was discovered that NEMS was using an October-peaking load shape to represent residential space cooling, which suppressed peak effects to levels lower than expected. An apparent scaling down of the annual load within the load-demand submodule was found, another significant suppressor of the peak impacts. EIA promptly responded to Berkeley Labs discoveries by updating numerous load shapes for the AEO2002 version of NEMS; EIA is still studying the scaling issue. As a result of this work, it was concluded that Berkeley Labs customary end-use decrement approach was the most defensible way for Berkeley Lab to perform the recent CAC utility impact analysis. This approach was applied in conjunction with the updated AEO2002 load shapes to perform last years published rulemaking analysis. Berkeley Lab experimented with several alternative approaches, including modifying the CAC efficiency level, but determined that these did not sufficiently improve the robustness of the method or results to warrant their implementation. Work in this area will continue in preparation for upcoming rulemakings for the other peak coincident end uses, commercial air conditioning and distribution transformers.