The project will accelerate commercialization of large scale mobile (PEV) and fixed grid storage through ensuring interoperability of multifunctional devices with enhanced value proposition. This storage project is also a major first step leading to a future campus scale microgrid at NIST involving PV arrays, electric vehicles, NIST Net Zero home, all coupled with storage, to provide an integrated microgrid system. A Distributed Smart Grid Storage System can simultaneously provide value (and accrue revenue) for several applications including 1) providing local power quality, solar cloud ramprate smoothing and enabling microgrid operation for outages; 2) enhancing the delivery system performance by leveling peak power flow through constricted grid interconnections; and 3) participating in wide area system operator ancillary service markets such as frequency regulation. Advanced battery technologies (e.g., LithiumIon chemistries) provide good value for the high power, short duration (<1hr) storage cycles needed to address the above applications, where different battery chemistries provide different cost tradeoffs between power, energy, weight/volume density (for electric vehicles), and cycle life capabilities (charge/discharge cycle depth, rate, and number of cycles). The NIST project provides research and coordination to ensure interoperability of the many standards development organizations addressing various aspects of these rapidly emerging advanced batterybased distributed storage systems including safety codes, provides models for advanced battery system performance in grid storage applications, and provides interoperability test procedure development and storage system performance evaluation for a wide range of grid scenarios encountered by customer and community energy storage systems including electric vehicles as grid storage.
Objective - Establish interoperable electrical and information exchange standards, performance models, and measurement methods for smart grid and microgrid integration of high-speed battery storage systems focused on community and customer domain devices (including electric vehicles as grid storage).
What is the Technical Idea? The rapid rise in distributed, renewable energy resources, including residential photovoltaics, is driving fundamental changes in our electrical infrastructure, including new operational and regulatory requirements and new expectations among consumers. The future grid that will emerge from this rapidlyevolving landscape has new measurement and interoperability challenges that are being addressed through NIST’s smart grid test bed project portfolio, with one exception. That exception is the essential role that energy storage capability must play in providing for a stable and manageable future grid. This proposed new project addresses that gap by adding high-power storage and associated energy management methodologies to the microgrid interoperability testbed, and by using this Energy Storage Systems (ESS) to conduct research on the role of storage in microgrid island mode operation and grid support during grid-conneceted mode. The project will develop technology underpinnings of ESS energy mananment systems (EMS), grid storage application performance models, and the measurement methods and standards needed for effective grid integration and utilization of ESS devices.
Distributed highspeed ESS devices utilizing advanced battery technologies and smart inverter interconnection equipment can in principal simultaneously provide value for many applications, thus increasing the value proposition of the installed systems; and hence incent pervasive deployment. However, this will require a new EMS paradigm where the highly distributed ESS devices provide fast local customer and distribution grid support needed for resiliency and power quality, while simultionsly participating in wide area grid support for stability and capacity utilization. The NIST project will address the interoperability requirements for customer and grid support functions of of ESS including the following:
The local customer and distribution system applications for highspeed storage include improving power quality, smoothing ramprates of photovoltaicsolar from clouds, and enabling microgrid operation for outages. In microgrid applications, distributed storage can be a primary enabler by providing generation during short outages and transitions to island mode, and by enabling local rotating generators to operate at more optimal power levels and cycling rates. The same distributed storage system can smooth ramp rates of local solar generators that can affect local power quality and can interfere with local distribution system devices and operations (Ramp rate regulatory requirements are being considered by California PUC Rule 21 Smart Inverter Working Group). High speed distributed storage systems can reduce the ramp rates to no faster than a minute to meet utility needs, while also allowing photovoltaic solar system integrators to use maximum power point tracking to capture all available solar energy.
Power Transmission and Distribution delivery system assets typically must be sized for the peak power level that is only needed for a short period of time during the day. Aggregated highspeed distributed storage can level the peak power flowing through the constricted grid interconnections, thus reducing the capital equipment investment needed to service peak load events. In 2011, a FERC ruling permitted higher market rates for participation in fast frequency regulation that can be provided by highspeed battery storage systems, in contrast to the lower market rates for the less valuable slower response frequency regulation that is provided by rotating machine generators. In 2014, the California Public Utility Commission in response to California legislation set a total state energy storage target of 1.3 GW by 2020. These are major drivers (and mandates) for rapid deployment of highspeed storage that can also provide the other benefits discussed above.
What is the Research Plan? The NIST distributed storage project will provide interoperable standards, measurement methods and data that will enable battery-based distributed Smart Grid Storage Systems to capitalize on multiple value streams, and will provide certainty in markets by better defining the cost and value of providing the various grid storage functions.
In 2009, NIST authored and chaired the Smart Grid Interoperability Panel (SGIP) priority action plan that coordinated standards for Distributed Energy Resources with a focus on distributed storage. NIST has continued to provide leadership in this area through the SGIP Distributed Renewables, Generation and Storage Domain Expert Working Group (DRGS DEWG). The NIST distributed storage project will continue to participate and provide leadership on distributed storage system standards working groups focused on interconnection standards, information model standards, and test and safety standards including:
In 2011, NIST convened the High Megawatt PCS workshop at the Pentagon to aid in identifying “PCS Architectures for PEV Fleets as Grid Storage” (http://www.nist.gov/pml/high_megawatt/jun2011_workshop.cfm). This was part of the DOD goal to mitigate the cost of PEVs at military bases by using them as grid storage when they are not being driven (http://www.whitehouse.gov/blog/2011/09/09/air-force-jumpstarts-electric…). The NIST project will demonstrate interoperability of distributed smart grid battery storage systems for the use cases and standards discussed above. The project leverages other projects within the NIST Smart Grid Office research portfolio and the unique NIST smart grid testbed including the grid scenario emulator and Microgrid/PCS lab.