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Energy Systems Integration News

Photo of a man fueling a hydrogen car.

NREL engineer Danny Terlip fuels a Mercedes Benz B-Class Fuel-Cell vehicle at a state-of-the-art hydrogen dispensing system at the Energy Systems Integration Facility (ESIF) at NREL. The dispensing station has a 350 and 700 bar capability from a dual dispenser.

September 2015

Welcome to Energy Systems Integration News, NREL's monthly recap of the latest energy systems integration (ESI) developments at NREL and worldwide.

Have a news item we should include in our next issue? Email us at

In This Issue


NREL Signs Agreement With China's National Utility

NREL and China's State Grid Energy Research Institute (SGERI) have signed a first-ever memorandum of understanding to coordinate on ESI research projects.

The State Grid Energy Research Institute, located in Beijing, is a subsidiary of China's national utility, State Grid Corporation of China. China has announced plans to strengthen its national grid so that it can more effectively deliver electricity generated by both conventional and renewable methods.

The agreement between the NREL and SGERI lays out a general framework for coordination between the two organizations, and is intended to spark discussions for creating more specific R&D collaborations in the future.

NREL's agreement with State Grid focuses on three key areas: power system planning and operation support, energy systems integration, and market design. On the U.S. side, NREL will have access to huge amounts of data as China changes how its electricity is produced, transmitted, and used.

A potential outcome resulting from the two organizations working together could be the creation of a partnership to inform policymakers about energy and sustainable development.

Register for NREL's Workshop on Integrating PV in Distributed Grids

Join us on October 22 and 23 at NREL's Energy Systems Integration Facility (ESIF) for a workshop showcasing the latest research and advanced technologies for integrating high penetrations of PV in distribution grids.

Get more information and register.

New Rooftop Solar Resource Monitoring System Installed at the ESIF

A new station recently installed on the roof of the Energy Systems Integration Facility (ESIF) adds additional measurement capability to existing monitoring stations at NREL. There have been various solar monitoring stations across the NREL campus and on the SunEdison photovoltaic (PV) plant operating since 2009. The network has existed in various configurations since then, all of which can be found on the Measurement and Instrumentation Data Center (MIDC). NREL recently revamped the system such that there are more stations being added to the network.

Additional measurements are being taken such that the following are now available: plane-of-array irradiance, latitude-tilt irradiance, back-of-panel PV temperature, ambient temperature, and relative humidity. Data are being taken every second with a silicon diode pyranometer, namely, the LI-200. The accuracy of the timing for the one-second data is maintained with a GPS device. Additional improvements include a once- or twice-a-week cleaning of the radiometers and a calibration of the sensors each year. Data is communicated back to MIDC in a number of ways depending on the location.

These data have already proven useful to some researchers on campus and will be beneficial for future studies related to short-term forecasting and the effects of the variability in radiation on power output.

Learn more about NREL'sresource assessment and forecasting work.

NREL Researcher Presents WWSIS Phase 3 Results to Industry Officials

Last month, NREL's Kara Clark presented the results of the Western Wind and Solar Integration Study (WWSIS) Phase 3 to 35 industry and utility representatives from the Southwest Area Transmission, Sierra Subregional Planning Group, Colorado Coordinated Planning Group, the Western Interstate Energy Board, and various consulting organizations at the WestConnect Regional Planning meeting in Denver.

The meeting's participants also included agents from Tucson Electric, Black Hills Energy, Sacramento Municipal Utility District, Western Area Power Administration, Public Service of New Mexico, and Tri-State Generation and Transmission along with representatives from regulatory agencies such as Arizona Corporation Commission, Colorado Public Utilities Commission, and Wyoming Infrastructure Authority.

Clark's presentation focused on the results of phase three of the study, which show that with good 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 power.

Learn more about the Western Wind and Solar Integration Study.

NREL Assesses Costs of Adding New Generation to Existing Power Systems

NREL was commissioned by the Wind Program of the U.S. Department of Energy to investigate three integration cost-related questions: (1) How does the addition of new generation affect a system's operating costs? (2) How do changes in generation mix and operating parameters and procedures affect costs? and (3) How do increases in variable generation (non-dispatchable wind and solar) impact the accuracy of natural gas orders?

The study, designed and executed in collaboration with a group of industry experts, examined how production costs vary with the addition of new baseload generation, increases in the amount of variable generation, and changes in generation mix, gas prices, and self-scheduling practices. Four aspects of production costs were investigated: generator cycling costs (i.e., start-up, shutdown, and ramping-related costs), non-cycling variable operations and maintenance costs, reserves provisioning costs, and fuel costs.

Download the conference paper for a summary of the work: A Systematic Approach to Better Understanding Integration Costs: Preprint

Download the full report to learn the detailed study conclusions: A Systematic Approach to Better Understanding Integration Costs

Hear from NREL's Energy System Integration Experts at Upcoming Events

Mark your calendar for these speaking engagements for NREL's ESI leadership.

  • October 1314, 2015: NREL Associate Lab Director for Energy Systems Integration Dr. Bryan Hannegan will speak at the2nd Annual National Summit on Smart Grid & Climate Change in Washington, D.C. Hannegan will participate in a roundtable discussion on the topic "Will new technologies and business models help utilities and tech companies address integrate distributed energy resources and address climate change mitigation and resilience?"

  • November 46, 2015: NREL's Dr. Martha Symko-Davies will speak on "Building the Grid Integrating Complexity" at the Empowering Customers & Cities event in Chicago, Illinois.

  • November 1718, 2015:Dr. Hannegan will speak on "The invaders: Disruptive technologies crowding the utility space" at the Utilities in a Time of Change and Challenge conference in Scottsdale, Arizona.

See the full list of upcoming NREL ESI events.

Finalists in Google and IEEE "Little Box Challenge" to Bring Inverters to NREL October 21

On October 21, each of the 18 finalists in theLittle Box Challenge presented by Google and the IEEE Power Electronics Society will bring their inverter to the Energy Systems Integration Facility (ESIF) for testing and evaluation against the contest parameters. The Challenge is an open competition to build smaller power inverters for use in solar power systems. The winner of the $1 million prize will have designed and built a kilowatt-scale inverter with the highest power densityat least 50 watts per cubic inch.

NREL researchers will evaluate each inverter's efficiency and performance during the same set of typical operating conditions spanning 100 hours. The test results will help Google decide the winner of the competitionwho will be announced sometime in late 2015 or early 2016.

Learn more about NREL's partnership with Google through the Challenge.

NREL to Host Greentech Media Grid Edge Meeting October 27

NREL is hosting Greentech Media's Grid Edge Executive Council meeting on October 27, 2015, in the Energy Systems Integration Facility (ESIF). The topic for this meeting is renewable integration at the grid edge. The discussions will be focused on examining the top drivers of renewable integration and the technology currently available to facilitate rapid grid connectivity. Other topics include identifying downstream impacts of more grid-connected renewables and some of the regional efforts currently underway.

NREL Hosts NERC Synchronized Measurement Subcommittee Meeting Last Month

On September 2 and 3, NREL hosted the North American Electric Reliability Council (NERC) Synchronized Measurement Subcommittee Meeting. This was a kickoff meeting for a new NERC task force on synchronized measurements, with a focus on developing priorities for NERC with regards to phasor measurement unit usage for reliability standards, state estimation, and generator model validation. NERC representatives are considering asking NREL to host future NERC meetings on various topicswhich could bring in utilities and other stakeholders that may be future partners in R&D work.

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ESI in the U.S. and Around the World

iiESI Update: ESI 102 Workshop Presentations Available, Thermal Energy Workshop in Korea Next Month

Download presentations from the International Institute for Energy Systems Integration (iiESI)'s ESI 102 workshop last month, and register for next month's event in Korea. iiESI is a global institute aimed at tackling the challenges of energy systems integration through collaboration and education.

  • The ESI 102 workshop was held August 37, 2015, at the Energy Systems Integration Facility at NREL. The course covered the research challenges of ESI at all scales (from residential to continental) across multiple energy (and non-energy) domains from a technical, market, regulatory, and consumer standpoint. The course was designed to give a snapshot on the state of the art in ESI and the research challenges. The course was designed for graduate students and practitioners working in the field with a very diverse set of backgrounds. See the workshop agenda and presentations.

  • iiESIand the Korea Institute of Energy Research are co-sponsoring the workshop "ICT Enabling Thermal Energy Flexibility in Integrated Energy Systems" next month in Korea. The workshop will follow the World Science and Technology Forum, hosted by the Ministry of Science, ICT, and Future Planning of the Republic of Korea on October 1920, 2015, in Daejeon, Korea. Register and get more information about the event.

Watch for upcoming issues ofEnergy Systems Integration News for more iiESI updates.

Energy Department's Second Quadrennial Technology Review Assesses Grid Modernization Technologies

Released this month, the Energy Department's 2015 Quadrennial Technology Review (QTR 2015) examines the most promising research, development, demonstration, and deployment (RDD&D) opportunities across energy technologies to effectively address the nation's energy needs. Notably, the report identifies seven high-impact RD&D areas needed to build the fundamental capabilities required for a modern electric power grid.

The insight gained from this analysis provides essential information for decision makers as they develop funding decisions, approaches to public-private partnerships, and other strategic actions over the next five years.

Learn more about the QTR 2015.

U.S. Deploys 40.7 Megawatts of Energy Storage in Second Quarter of 2015

In the second quarter of 2015, the U.S. energy storage market had its best quarter in two and a half years, installing 40.7 megawatts of capacity, according to the Energy Storage Association (ESA). While the figure is a nine-fold increase year-over-year, this increase was mainly driven by one large utility project, although underlying trends show great promise for other markets. The ESA projects that 2015 will be the biggest year yet for energy storage, with a total of 220 megawatts planned or already deployed.

See the ESA news release and the executive summary of the ESA's "U.S. Energy Storage Monitor" for the second quarter of 2015.

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Who's Who at the ESIF

See Who Visited the ESIF in August

Recent visitors to the Energy Systems Integration Facility (ESIF) include:

  • National Rural Electric Cooperative Association
  • North American Electric Reliability Corporation
  • Dr. Hermann Tribukait, Representative of the Energy Sustainability Fund of Mexico
  • Gerardo lvarez Franyutti, Vice-President, Energy Business Group, Mexichem

You can tour the ESIF, too. Contact us today to schedule your own ESIF visit.

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