As California seeks to meet its ambitious goals for carbon reduction and support of an electric grid with high levels of renewable energy supply, there is a growing need for large amounts of flexibility from the demand side. This report outlines a system architecture and technology infrastructure to enable dynamic pricing to be used to finely tune coordination between the grid and its customers. Taking a cue from the success of internet architecture, this system — Price-Based Grid Coordination — emphasizes simplicity and universality. It enables a wide variety of ways for prices and other signals to pass from the grid to individual flexible loads and other devices, including multiple possible locations for the intelligence that combines price signals with device functional needs. The report includes a reference data model to knit together information at the utility level, communication protocols, and customer devices, to be independent of any particular protocol. The report also contains a roadmap for technology standards development needs, and a review of the current California policy developments that intersect dynamic pricing.
The Oakland EcoBlock project (EcoBlock) seeks to develop a microgrid within an existing city block in Oakland California as a demonstration project on the viability of retrofitting an existing block of residential and commercial buildings into a microgrid capable of islanding from the grid. EcoBlock has considered a variety of different potential regulatory frameworks that might accommodate the objectives of the project. Based on an analysis of current law, the working model has been to rely upon existing provisions within the Public Utilities Code that recognize the right of individuals to install and operate electric equipment outside of Commission regulation if the generation, storage and distribution of power is limited to the owners’ “own use.” This white paper examines the “own use” exemption in section 218 of the Public Utilities Code and explores its potential as well as its limitations in the context of microgrids and recent Commission action. In so doing, it touches upon the recently issued Microgrid Proceeding Proposed Decision (Microgrid PD), the Commission Staff paper upon which the PD is premised and issues that arise out of both. This white paper, however, is not intended to be a critique of either and, rather, is intended to prompt questions and reflections on how the policy decisions made in these documents will foster or retard the development of projects like EcoBlock.
This project demonstrated that solar PV can be recruited to stabilize the grid, smooth out disturbances, manage power flows, and assist circuit switching operations. It developed a radically new, layered control framework for Distributed Energy Resources (DER) to act in response to real-time, measured conditions on their local distribution circuit, rather than waiting for a price signal to indicate preferred behavior. By enabling resources to act as good citizens on the electric grid, Phasor-Based Control (PBC) facilitates arbitrarily high solar penetration levels.
Phasor-based interdependencies of multiple harmonic sources, especially Distributed Energy Resources, on distribution networks are analyzed in this paper. A new index, Phasor Harmonic Index (IPH), is proposed by the authors. IPH considers both harmonic source magnitude and phase angle for different harmonic orders. Other commonly used harmonic indices are based solely on magnitude of waveforms. A very detailed model of a distribution network is used in the harmonic assessment. With the help of the detailed distribution network model, the phase couplings and the phase balancing impacts on harmonic propagation between three phases are investigated. Moreover, effects of harmonic source phase angle deviations are analyzed at both the customer side and the substation side. This paper investigates the importance of phase angles in harmonic assessment and how distribution netwo
This interdisciplinary eXtensible Building Operating System–Vehicles project focuses on controlling plug-in electric vehicle charging at residential and small commercial settings using a novel and flexible open-source, open-architecture charge communication and control platform. The platform provides smart charging functionalities and benefits to the utility, homes, and businesses.
This project investigates four important areas of vehicle-grid integration research, integrating technical as well as social and behavioral dimensions: smart charging user needs assessment, advanced load control platform development and testing, smart charging impacts, benefits to the power grid, and smart charging ratepayer benefits.
Widespread deployment of EcoBlocks has the potential to transform today's electricity system into one that is more resilient, flexible, efficient and sustainable. In this vision, the system will consist of self- su cient, renewable-powered, block-scale entities that can deliberately adjust their net power exchange and can optimize performance, maintain stability, support each other, or disconnect entirely from the grid as needed. This report is intended as an independent analysis of the potential relationships, both constructive and adverse, between EcoBlocks and the grid.
This project developed and field-tested two methods of Adaptive Protection systems utilizing synchrophasor data. One method detects conditions of system stress that can lead to unintended relay operation, and initiates a supervisory signal to modify relay response in real time to avoid false trips. The second method detects the possibility of false trips of impedance relays as stable system swings “encroach” on the relays’ impedance zones, and produces an early warning so that relay engineers can re-evaluate relay settings. In addition, real-time synchrophasor data produced by this project was used to develop advanced visualization techniques for display of synchrophasor data to utility operators and engineers.
This white paper describes the circumstances in California around the turn of the 21st century that led the California Energy Commission (CEC) to direct additional Public Interest Energy Research funds to address critical electric grid issues, especially those arising from integrating high penetrations of variable renewable generation with the electric grid. It contains an assessment of the beneficial science and technology advances of the resultant portfolio of electric grid research projects administered under the direction of the CEC by a competitively selected contractor, the University of California’s California Institute for Energy and the Environment, from 2003-2014.
In recent years, extreme weather events have severely affected the performance of the electric grid. Very large-scale events (VLSE) with potentially catastrophic impacts on the grid pose more than an inconvenience in today's electricity-driven lifestyle, and the frequency and severity of such events may continue to increase as a consequence of global climate change. This article summarizes the state of the art in leveraging distributed resources to improve resilience of the electric grid. It also highlights the technical questions that need to be addressed through additional research and development if the value of distributed resources is to be maximized. Published in "Power and Energy Magazine", Volume: 12, Issue: 5