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Energy Systems Integration News

February 2015

Photo of the Energy Systems Integration Facility with the words ESIF 2014.

The ESIF 2014 Annual Report details research highlights, awards, partnerships, capabilities, and other achievements for the facility in its first year of operation.

Welcome to Energy Systems Integration News, NREL's monthly newsletter designed to keep industry partners, stakeholders, associations, and educational institutes up to date on the latest energy systems integration (ESI) developments at NREL and worldwide.

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In This Issue


Check Out the 2014 ESIF Annual Report

The Energy Systems Integration Facility (ESIF) 2014 Annual Report is now available for download.

The report details research highlights, awards, partnerships, capabilities, and other achievements for the ESIF in its first year of operation.

Download the report.

Testing at NREL Aids Solar Power in Hawaii

Inverter load rejection overvoltage tests completed by NREL with partner SolarCity have proven so successful that Hawaiian Electric Companies (HECO) has proposed to double its hosting capacity for solar energy.

The inverter testing at NREL's Energy Systems Integration Facility (ESIF) examined ways to quantify transient LRO, which is one of the main technical barriers to allowing more distributed energy, such as solar and wind, onto the grid. Results of the testing are discussed in the report, Inverter Load Rejection Over-Voltage Testing: SolarCity CRADA Task 1a Final Report.

Based on the results of these tests, HECO announced in a January 20 filing with the Hawaii Public Utilities Commission its intention to increase its penetration limits for rooftop solarfrom the current limit of 120% of minimum daytime load (MDL) to 250% of MDL. If those increases are implemented, they will represent the highest threshold for solar penetration on distribution circuits in the United States.

LRO conditions can occur when a local feeder or breaker opens and the power output from a distributed energy resource exceeds the local load. These LRO issues have been driving HECO's current limitations on high penetration of distributed generation on the utility's feeders. Results from NREL testing helped to mitigate some of HECO's LRO challenges generated from advanced photovoltaic inverters.

Learn more about NREL's partnership with SolarCity and HECO.

NREL Handbook Helps Industry Collect and Interpret Solar Resource Data for Solar Energy Applications

Reliable information about the solar resource is required for every solar energy application, from small installations on a rooftop to large solar power plants. However, solar resource information is of particular interest for large installations, because they require substantial investment, sometimes exceeding $1 billion in construction costs. Before such a project is undertaken, the best possible information about the quality and reliability of the fuel source must be made available-that is, project developers need to have reliable data about the solar resource available at specific locations, including historic trends with seasonal, daily, hourly, and (preferably) subhourly variability to predict the daily and annual performance of a proposed power plant. Without this data, an accurate financial analysis is not possible.

Released this month, Best Practices Handbook for the Collection and Use of Solar Resource Data for Solar Energy Applications presents detailed information about solar resource data and the resulting data products needed for each stage of a solar energy project, from initial site selection to systems operations. It also contains a summary of solar forecasting and its development throughout the last few years. The U.S. Department of Energy's Solar Energy Technologies Office, project developers, engineering procurement construction firms, utility companies, system operators, energy suppliers, financial investors, and others involved in solar energy systems planning and development will find this handbook to be a valuable resource for the collection and interpretation of solar resource data. This handbook is expected to be used as a reference during each project stage.

The handbook is a comprehensive update of NREL's 2010 publication Concentrating Solar Power: Best Practices Handbook for the Collection and Use of Solar Resource Data, which was developed in response to a growing need by the solar energy industry for a single document to address the key aspects of solar resource characterization and recommend to industry the best way to use solar resource data for site selection and estimating power plant performance. As the solar energy industry has developed rapidly throughout the last few years, there have been significant enhancements in the body of knowledge in the areas of solar resource assessment and forecasting. Thus, this second version of the handbook was developed to update and enhance the initial version and present the state of the art in a condensed form for all of its users. It was also decided that additional solar technologies, such as photovoltaics, would be incorporated along with additional aspects of energy meteorology that have become extremely important, such as solar forecasting.

While the first version of the handbook was developed by NREL researchers, the updated version has additional contributions from an international group of experts primarily from the knowledge that has been gained through participation in the International Energy Agency's Solar Heating and Cooling Programme Task 36 and Task 46.

Learn more about NREL's resource assessment and forecasting work.

Watch How NREL Is Redefining What's Possible for Renewable Energy With Grid Integration

NREL is spearheading engineering innovations that will help optimize the entire energy system, and the lab's analysis capabilities complement that engineering work by identifying ways to integrate renewable energy effectively and economically. A new video released by the NREL Energy Analysis program shows how NREL research and analysis are redefining what's possible for renewable energy on the grid.

Watch the 3-minute video here: Redefining What's Possible for Renewable Energy: Grid Integration.

NREL Study Launches Computational Simulations of Eastern Interconnection

This month, NREL's Eastern Renewable Generation Integration Study (ERGIS) team launched more than 700 simulations on the Energy Systems Integration Facility's Peregrine computing cluster.

This effort is the latest piece of ongoing research on the impact of renewable energy on the Eastern Interconnection. These simulations will take more than 300,000 node hours, and the resulting analysis will be presented to a technical review committee in Washington, D.C., this spring.

ERGIS is a multiyear, multiprogram-funded project aimed at understanding the operational impacts of high penetrations of wind and solar generation on the Eastern Interconnection by providing the highest-resolution analysis of the largest power system in the world, complete with detailed generation and transmission representation. The study aims to demonstrate that wind resources are a capable resource for meeting 20%25% of the Eastern Interconnection's electricity needs. Researchers will also explore regional impacts and relationships between wind and solar resources.

Better understanding of how wind power affects utility operations allows the industry and policy makers to make more informed decisions about the integration of wind technologies, which may in turn support further development and deployment of wind power.

Learn more about ERGIS.

WWSIS-3 Results Highlighted in Power Engineering

A recent article in Power Engineering magazine highlights key findings of NREL and General Electric's Western Wind and Solar Integration Study Phase 3 (WWSIS-3).

Released in December 2014, WWSIS-3 finds that with good system planning, sound engineering practices, and commercially available technologies, the Western Interconnection can withstand the crucial first minute after grid disturbances with high penetrations of wind and solar on the grid.

Read more about the Western Wind and Solar Integration Study.

Upcoming Speaking Engagements for NREL ESI Leadership

Mark your calendars to see NREL's Bryan Hannegan and Martha Symko-Davies at three upcoming conferences.

  • 2015 Cleantech Forum, March 1618, 2015, in San Francisco, California: Dr. Martha Symko-Davies will speak on "Changing the Grid Infrastructure."

  • Airports Council International 2015 Environmental Affairs Conference, March 2225, 2015, in Vancouver, British Columbia: Dr. Martha Symko-Davies will speak on "Microgrids and Other Innovative Energy System Developments."

  • Grid Transformation Summit 2015, April 2729, 2015, in New York, New York: Bryan Hannegan will give a keynote address.

A full list of upcoming NREL ESI events is available.

NREL Achieves Milestone in Commission of New Hydrogen Fueling Station

This month, NREL achieved a milestone in the lab's commission of a new hydrogen fueling station with the first 700-bar precooled hydrogen fueling event at NREL and in the state of Colorado.

While the team has some remaining steps to completely qualify the system under NREL's readiness verification process, these new hydrogen production, compression, storage, and dispensing capabilities will provide stakeholders a unique test platform to help move the hydrogen and fuel cell industry forward.

Animation: Connecting Electric Vehicles to the Grid

A sustainable transportation future will rely on innovative systems connecting vehicles, utilities, renewable energy sources, and buildings.

NREL is working with partners to develop electrified transportation systems that allow electric vehicles (EVs) to interact with the power grid, providing the opportunity to shift transportation energy demands from petroleum to electricity.

This animation depicts a potential future transportation scenario in which EVs are charged via electrified roadways (e-roadways).

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ESI in the U.S. and Around the World

Energy Department, Arizona Utilities Announce Transmission Infrastructure Project Energization

The U.S. Department of Energy's Western Area Power Administration and a group of Arizona utilities celebrated the energizing of a new transmission infrastructure project that will serve the state's growing electrical energy needs, attract renewable energy development to the area, and strengthen the transmission system in the Southwest.

The 109-mile Electrical District No. 5-to-Palo Verde Hub (ED5-PVH) transmission project in Arizona advances America's energy infrastructure by eliminating system constraints and providing increased capacity access to affordable energy in the region.

Learn more about the project.

DOI Approves Southwest Transmission Line to Modernize Grid

Last month, the U.S. Department of the Interior (DOI) announced the approval of the $2 billion SunZia Southwest Transmission Line Project, a major infrastructure project for the West.

The project will help enable future development of wind and solar energy from New Mexico and Arizona, providing renewable power to the growing desert Southwest region.

Read more about the project.

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Who's Who at the ESIF

See Who Visited the ESIF in January

Several organizations visited NREL's Energy Systems Integration Facility (ESIF) last month. Visitors included:

  • Akonia Holographics
  • Argonne National Laboratory
  • Behrent Engineering
  • Colorado Oil & Gas Association
  • Denver Water
  • Frito-Lay
  • Innovators International
  • Marriott
  • RES Americas
  • Schneider Electric
  • Thermo Scientific
  • U.S. Department of Defense

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