Glossary

Term Definition Examples
Announcement Date The date the project was publicly announced.  
Benefit Stream Affected The benefit stream(s) affected by this policy. Frequency Regulation
Black Start A black start is the process of restoring a power station to operation without relying on the external electric power transmission network. An energy storage system is used to re-start turbines of a generation facility after a large blackout causes generators to go offline.
Capital Expenditure (CAPEX) The total up-front capital expense of the system stated in dollars. 2000000
Commisioning Date The date the project was electrically activated, or "turned on".  
Construction Date The date construction commenced on the project.  
Debt Provider The primary debt provider in the project.  
Decommisioning Date The date the project became inoperative or was "turned off".  
Developer The person or organization responsible for organizing the development and implementation of the energy storage project.  
Duration at Rated Power The amount of time (in HH:MM) the storage system can output at its rated power capacity. 02:30
Effective Date The date the policy becomes effective.  
Electric Bill Management Energy storage used by end-use customers in a variety of facets to reduce electric bills. Can be used to eliminate demand charges, charge during off-peak to reduce peak consumption, etc.
Electric Bill Management w/ Renewables Energy storage used by end-use customers in a number of facets, and in conjunction with renewable generation resources, to reduce electric bills. Smooth the output of solar panels to eliminate the risk of high demand charges during peak hours when the solar drops off.
Electric Energy Time Shift Energy time shift involves storing energy during low price times, and discharging during high price times.  
Electric Supply Capacity Depending on the circumstances in a given electric supply system, energy storage could be used to defer and/or to reduce the need to buy new central station generation capacity and/or to ‘rent’ generation capacity in the wholesale electricity marketplace.  
Electric Supply Reserve Capacity - Non-Spinning Generation capacity that may be offline, or that comprises a block of curtailable and/or interruptible loads, and that can be available within 10 minutes. Unlike spinning reserve capacity, non-spinning reserve capacity is not synchronized with the grid (frequency). Non-spinning reserves are used after all spinning reserves are online.  
Electric Supply Reserve Capacity - Spinning Generation capacity that is online but unloaded and that can respond within 10 minutes to compensate for generation or transmission outages. ‘Frequency-responsive’ spinning reserve responds within 10 seconds to maintain system frequency. Spinning reserves are the first type used when a shortfall occurs.  
Enacted Date The day the policy was officially accepted.  
Energy Storage Project Name The official or unofficial title of the project. Bath County Pumped Storage Station
Energy Storage Technology Provider The company that provides the energy storage technology itself. A123 Systems
EPC Stands for "Engineering, Procurement, Construction" - Identifies the entity or entities that performed any or all of these services for the project. DBR Construction
Equity Owner The (or one of the) owner(s) of the system, or the entity that holds "title" to the equipment. Southern California Edison; First Wind
Equity Owner Percentage The percent equity held by each owner of the project.  
Expiration Date The day on which the policy is no longer effective.  
Frequency Regulation Frequency regulation involves moment-to-moment reconciliation of the supply of electricity and the demand for electricity. The reconciliation is done every few seconds. So at any given moment, if electricity demand exceeds supply then the supply is increased to meet demand. And, if demand is less than supply then the supply is decreased.  
Grid Connected Commercial (Reliability & Quality) The electric reliability application entails use of energy storage to provide highly reliable electric service. In the event of a complete power outage lasting more than a few seconds the storage system provides enough energy to a) ride through outages of extended duration or b) to complete an orderly shutdown of processes, c) transfer to on-site generation resources. The electric power quality application involves use of energy storage to protect loads downstream against short duration events which affect the quality of power delivered to the load. Some manifestations of poor power quality include: • variations in voltage magnitude, (e.g., short-term spikes or dips, longer-term surges, or sags) • variations in the primary 60 cycles/sec frequency at which power is delivered • low power factor (voltage and current excessively out of phase with each other) • harmonics, (i.e., the presence of currents or voltages at frequencies other than the primary frequency) • interruptions in service, of any duration, from a fraction of a second to minutes  
Grid-Connected Residential (Reliability) The electric reliability application entails use of energy storage to provide highly reliable electric service. In the event of a complete power outage lasting more than a few seconds the storage system provides enough energy to a) ride through outages of extended duration or b) to complete an orderly shutdown of processes, c) transfer to on-site generation resources.  
Grid Interconnection The level at which an energy resource (such as generation or storage) connects to the grid. An energy resource could be connected at Transmission, Primary Distribution, or Secondary Distribution levels. Transmission; Secondary Distribution
Grid Interconnection Affected The grid interconnection type affected by this policy. Transmission; Primary Distribution
Incentive Affected The name of the incentive(s) affected by the policy. Treasury Grant 1603
Incentive Amount The amount of incentive given to the project. 1200000
Incentive Source The entity that provides the incentive to the project. California Self Generation Incentive Program Administrators
Incentive Title The official or unofficial title of the incentive program received by the project. Self-Generation Incentive Program
Integrator Company The organization that brings together component subsystems into a whole and ensures that those subsystems function together as specified. ABB
ISO/RTO (Independent System Operator/Regional Transmission Organization) The ISO or RTO that manages the grid where the energy storage system is installed, if applicable. In the areas where an ISO is established, it coordinates, controls, and monitors the operation of the electrical power system, usually within a single US State, but sometimes encompassing multiple states. RTOs typically perform the same functions as ISOs, but cover a larger geographic area. CAISO; NYISO
Load Following Load following resources’ output changes in response to the changing balance between electric supply (primarily generation) and end user demand (load) within a specific region or area, over timeframes ranging from minutes to a few hours.  
Location The physical location of the energy storage project. (Address, City, State, Zip, Country)  
Onsite Renewable Generation Shifting Energy storage to perform renewables energy time-shifting for end-use customers that generate renewable power onsite. A production plant has a microturbine that generates excess power at night. They use the battery to store that excess energy and use it during peak price daytime hours.
Operating Expenditure (OPEX) Operating expenses in dollars per kWh of capacity per year. It is assumed that such operating expenses would be recurring throughout the life of the project. 800/kWh/year
Operations and Management (O&M) Contractor The company or group that operates and manages the energy storage system.  
Ownership Model A description identifying the relationship of the project owner to the project itself. Third-Party-Owned, Customer-Owned
Ownership Model Affected The ownership model(s) affected by this policy. Third-party-owned
Paired Grid Resource The source of energy that charges the ESS. Wind; Grid
Performance Any performance statistics or results available on the project. The system performed at a capacity factor of 90% during the year of 2010. Other examples of performance statistics include: - Round Trip Efficiency (RTE) - Ramping Rate - Greenhouse Gas Emissions - Noise (decibels) - Availability - Number of maintenance visits
Picture A high-resolution JPEG if available.  
Policy Description A brief summary of the policy in general and how it relates to storage. AB 2514 requires the CPUC to open a proceeding to determine apporpriate utility procurement targets, if any, for energy storage systems that are commercially available and cost-effective
Policy Name The official or unofficial name of the policy. The Self Generation Incentive Program
Policy Number The assigned tracking number for a given policy. R. 11-09-011
Policy Source The agency or body that created or approved the policy. California Public Utilities Commission
Power Electronics Provider The company that provides the power electronics (such as inverters) for the storage project. Satcon Power Systems
Primary Project Contact A person to contact for information about the project. (Name, Phone, Email, Address)  
Project Description A short description of the project that includes size, technology, city/state, and application. A 270 MW Underground Compressed Air Energy Storage Plant in Des Moines, Iowa that performs the tasks of energy time shifting and renewable resource firming for a nearby wind plant.
Projected Project Lifetime The number of years a project is expected to remain in operational condition, from date of commisioning. 15 years
Ramping Changing the loading level of a Generating Unit in a constant manner over a fixed time (e.g., Ramping up or Ramping down). Such changes may be directed by a computer or manual control.  
Rated Power The total possible output from the energy storage system, expressed in kW. 600kW
Renewable Energy Time-shift Centralized or distributed Electric Energy Time Shifting specifically related to the uncontrollable nature of renewable generation. Using an energy storage system to capture excess energy generated by grid-connected wind and solar farms during low demand times in order to dispatch it during high demand times.
Renewables Capacity Firming Use of storage to mitigate rapid output changes from renewable generation due to: a) wind speed variability affecting wind generation and b) shading of solar generation due to clouds. It is important because these rapid output changes must be offset by other “dispatchable” generation.  
Research Description A brief synopsis of the research being conducted, if applicable. Testing applications for the integration of solar PV with ESS for utility-scale systems.
Research Institution The name of the research institution affiliated with the project, if applicable. Solar Technology Acceleration Center; US Department of Energy
Research Institution Link A link to the relevant research institution affiliated with the project, if applicable. http://www.solartac.org/
Service/Use Case The benefits provided by the energy storage system. Services reference individual benefits and may come from direct market participation or reduced/deferred cost relative to the status quo. Use Cases are groups of (or sometimes individual) services that are provided by a single energy storage system. If possible, select from our pre-determined set values. Electric Energy Time-Shift; Renewables Capacity Firming; Frequency Regulation
Stationary Transmission and Distribution (T&D) Upgrade Deferral The T&D Upgrade Deferral benefit is related to the use of a relatively small amount of modular storage to: a) defer the need to replace or to upgrade existing T&D equipment or b) to increase the equipment’s existing service life (life extension). Storage for T&D equipment life extension is especially compelling for the aging fleet of underground circuits which are quite expensive to replace or to upgrade. Those circuits’ life can be extended by: a) reducing the number of ground faults and/or b) reducing loading such that operating temperature is reduced, which reduces degradation of the insulation.  
Status The current status of the energy storage project. Operational
Substation On-site Power Energy storage provides power at electric utility substations for switching components and for substation communications and control equipment when the grid is not energized.  
Technology Type The type of energy storage technology used in the project. If possible, select from our pre-determined set values. Advanced Lead Acid Battery; In-Ground Natural Gas Combustion Compressed Air Energy Storage
Transmission Congestion Relief In many areas, transmission systems are becoming congested during periods of peak demand, driving the need and cost for more transmission capacity and increased transmission access charges. Additionally, transmission congestion may lead to increased use of congestion charges or locational marginal pricing (LMP) for electric energy. Storage can be used to avoid congestion-related costs and charges. In this application, storage systems are installed at locations that are electrically downstream from the congested portion of the transmission system. Energy is stored when there is no transmission congestion, and discharged (during peak demand periods) to reduce transmission capacity requirements.  
Transmission Support Energy storage used for transmission support improves T&D system performance by compensating for electrical anomalies and disturbances such as voltage sag, unstable voltage, and sub-synchronous resonance. The result is a more stable system with improved performance (throughput). Benefits from transmission support are highly situation-specific and site-specific.  
Transportable Transmission and Distribution (T&D) Upgrade Deferral The T&D Upgrade Deferral benefit is related to the use of a relatively small amount of modular storage to: a) defer the need to replace or to upgrade existing T&D equipment or b) to increase the equipment’s existing service life (life extension). Storage for T&D equipment life extension is especially compelling for the aging fleet of underground circuits which are quite expensive to replace or to upgrade. Those circuits’ life can be extended by: a) reducing the number of ground faults and/or b) reducing loading such that operating temperature is reduced, which reduces degradation of the insulation. Transportable systems can be moved to where they are needed most on the grid.  
Utility The utility that administers the grid where the energy storage system is installed. Southern California Edison
Utility Type The type of utility, categorized by ownership. Investor-Owned
Utility Type Affected The type of utility affected by this policy. Investor Owned; Public Owned
Voltage Support To manage "reactance" at the grid system level, grid system operators rely on an ancillary service called ‘voltage support’. The purpose of voltage support is to offset reactive effects so that grid system voltage can be restored or maintained. "Reactance" occurs because equipment that generates, transmits, or uses electricity often has or exhibits characteristics like those of inductors and capacitors in an electric circuit.  
Web Link A link to the primary source for information on the policy/project, or a link to more information about the policy/project. http://www2.reupower.com/tes.asp