The DG case studies that follow highlight real world examples of microgrids and CHP, solar, and energy storage systems operating and providing resilience benefits (among others) to critical infrastructure sites. Case studies provide an excellent snapshot of how project challenges were overcome, and how individual facilities and end-users are maximizing the benefits from DG in order to enhance their overall facility or campus resilience. DOE’s CHP Project Profiles Database has two-page summaries profiling real world CHP projects with detailed information about system design, project costs, annual energy savings, environmental benefits, and more. Some CHP project profiles in CI are featured below.
Texas Medical Center (CHP)
The 48 MW CHP system at the Texas Medical Center provides electricity, steam, and chilled water to 45 buildings comprising an area of 19.3 million square feet, roughly 85% of the Texas Medical Center campus. The CHP system has been in operation since 2010 and provides $6-12 million in energy cost savings per year. While much of Houston and the surrounding area was without power during Hurricane Harvey, the Texas Medical Center's CHP system was able to provide life sustaining power for air conditioning, refrigeration, heating, and a number of other services. Although much of the surrounding Brays Bayou area was flooded, the elevated design of the CHP system allowed it to operate throughout the storm. More information can be found in DOE’s CHP project profile, Texas Medical Center and TECO, and DOE’s webpage, CHP Installation Keeps Hospital Running During Hurricane Harvey.
Greenwich Hospital (CHP)
The Greenwich Hospital is a 175 bed, 500,000 sq ft medical center located in Greenwich, CT. Its CHP system, installed in 2008, consists of two 1,250 kW natural gas-fired reciprocating engines. The hospital also has a 2,000 kW backup generator. Following Hurricane Sandy, the area surrounding Greenwich Hospital lost power for approximately 7 days. When the hospital lost grid power, it went down for about 7 seconds before the backup generators kicked in and power was restored. The transition from using grid power to operating solely on the CHP system went as planned, with the CHP system shutting down and restarting in island mode, while power was supplied to the hospital by backup generators. The whole transition process takes approximately 5 minutes. Due to its CHP system, Greenwich Hospital was able to continue normal operations throughout the storm. More information can be found in the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Mississippi Baptist Medical Center (CHP)
Located in Jackson, Mississippi, the Mississippi Baptist Medical Center experienced a complete electric grid outage for 52 hours during Hurricane Katrina in August 2005. The hospital’s 4.6 MW CHP system allowed the facility to continue operations while providing shelter, food, and clothing to stranded local citizens and displaced patients from other area hospitals. As the grid became unstable during the hurricane, the Mississippi Baptist Medical Center shed some load, disconnected from the power grid, and continued operation with the CHP system providing all power. The hospital ran for more than 50 hours, and it was the only such facility in the Jackson metropolitan area to remain nearly 100% operational. More information can be found in DOE’s CHP project profile, Mississippi Baptist Medical Center, and the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
South Oaks Hospital (CHP + Solar)
South Oaks Hospital, located in Amityville, NY on Long Island, has experienced significant energy cost savings and reliability benefits from their 1.3 MW CHP system and 47 kW solar PV array. The two duel-fuel reciprocating engines are able to supply all of the building's electricity needs, while the absorption chiller and two boilers have continued to supply steam for use in space heating and cooling, and domestic hot water production. The system has an overall efficiency of 82% and was able to pay itself back in under 5 years. During the 2003 blackout, South Oaks never lost power and was able to remain grid-isolated for 5 days, while the surrounding area lost power for 14 hours. Again, during Superstorm Sandy, the CHP system provided 100% of power. This allowed the facility to keep medications and food in freezers and refrigerators, provide service to patients from other facilities, and serve as a community center during the storm. More information can be found in the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Hospital De La Concepcion (CHP)
Hospital de la Concepcion, a 167-bed facility in San German, Puerto Rico installed a 2.8 MW CHP system in early 2017 in order to reduce energy costs and increase facility resiliency. The CHP system operates in 100% island mode and was able to provide critical power and thermal energy to the hospital throughout and after Hurricane Maria, serving life sustaining loads. The system is fueled by propane and is also equipped with a 250 ton absorption chiller that provides cooling and refrigeration services to the hospital. In addition to the critical services offered by the CHP system during and after Hurricane Maria, it is also anticipated to provide significant energy savings to the hospital in the future.
Princeton University (CHP + Solar)
The heart of Princeton's microgrid is a gas turbine CHP system capable of producing 15 MW. On sunny days, this power is supplemented by a 4.5 MW solar field. Princeton’s microgrid normally operates synchronized (connected) with the local utility. This benefits both the university and other local ratepayers. When the price of utility power is lower than Princeton’s cost to generate, the microgrid draws from the utility grid. However, when Princeton's microgrid can produce power less expensively than the utility, it will run to meet as much of the electricity needs of the university as possible. When Princeton’s microgrid can generate more than the university needs, and when the price of power on the utility grid is high, Princeton exports some power to earn revenues while lowering the net price of power for all other grid participants. More information can be found in the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Alaska Gateway School District – Tok School (CHP)
The Gateway School District in Tok, Alaska, installed a 120 kW boiler/steam turbine CHP system in 2013. The community of Tok is located approximately 200 miles east of Fairbanks and is surrounded by 8.5 million acres of forest in the Tok Management Area. Because of its remote location and small size (1,400 inhabitants), the high cost of fuel and electricity had a large impact on the local economy, especially the school. By installing a CHP system that could utilize the large amount of woody biomass fuel in the area, the school was able to provide 75% of the school’s electricity needs at a fraction of the cost. Furthermore, the excess heat from the CHP system was used to heat the school’s greenhouses, providing fresh produce year-round to the school and local community. More information can be found in DOE’s CHP project profile, Alaska Gateway School District Tok School, and the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
University of California San Diego (CHP + Solar + Energy Storage)
The University of California San Diego microgrid is one of the most advanced microgrids in the world. It provides 92% of the electricity and 95% of the heating and cooling needs for its 13 million square foot campus. The microgrid consists of 30 MW of CHP generation, 2.4 MW of solar PV, 300 kW of solar thermal, a 2.8 MW fuel cell, and 2.5 MW of battery storage. The CHP system is comprised of two 13.5 MW gas turbines and one 3 MW reciprocating engine, and serves nearly 85% of the entire campus' annual electricity loads. The cogeneration system has reduced UC San Diego's energy costs by approximately $9 million per year, increased overall system efficiency by limiting energy T&D losses, and relieved congestion on the surrounding San Diego Gas and Electric grid. More information can be found in DOE’s CHP project profile, University of California San Diego Microgrid.
Santa Rita Jail (CHP + Solar + Storage)
Santa Rita Jail, in Dublin, CA currently houses roughly 4,000 inmates in 18 separate housing units, and also contains additional service and administrative buildings throughout its 113-acre campus. The jail experienced multiple power reliability issues from 2002 to 2006, resulting in roughly 7.5 total hours without power during the 5-year period. In order to enhance onsite resilience, the jail installed multiple DERs over time, including a 1.4 MW molten carbonate fuel cell CHP system, 2 MW (4 MWh) of battery storage, 1.2 MW of solar PV, and additional diesel backup generators. The jail also incorporated the CERTS reliability framework and advanced controls into the microgrid to make it one of the most advanced microgrids in the world today. More information can be found in DOE’s CHP project profile, Alameda County Santa Rita Jail Microgrid.
Bergen County Utilities Authority (BCUA) (Renewable CHP)
The BCUA wastewater treatment plant installed a 2.8 MW biogas-fueled CHP system in 2008 in order to heat the five anaerobic digester tanks and provide the facility with roughly 90% of its electricity needs. The two Jenbacher JMS 420 engines are able to operate in parallel to the electric grid and are capable of running on either anaerobic digester gas or natural gas. The facility heavily relied on its CHP system during Sandy, which allowed the facility to process sewage for it 47 municipalities and roughly 550,000 customers during and after the storm. The facility is also able to aid in grid resiliency by participating in PJM’s Interconnection Demand Response Program. More information on the BCUA CHP system can be found in the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Breevort East (CHP)
The Breevort East high-rise co-op in Greenwich Village, NYC, installed a 300 kW CHP system in order to reduce electricity and thermal energy costs for the facility. Three natural gas-fired reciprocating engines are used to provide 300 kW of continuous power and 2,100 MBtu/h of thermal output for hot water. The recovered heat is also used to provide cooling via a 90 ton absorption chiller. The Brevoort was one of the only buildings in the lower third of Manhattan that was able to maintain power during the extended grid outages caused by the storm. The CHP system has also helped to provide the building with significant energy cost reductions. More information can be found in the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Public Interest Data Center (CHP)
The data center at Public Interest Network Services (PINS), located at 50 West 17th Street in Manhattan, provides hundreds of companies with office communications support. It is connected via three different fiber networks to multiple carriers for voice calls, provides multiple tier-1 Internet backbone operators, and is protected against power failure by a full-scale uninterruptible power supply (UPS) and CHP system. The 65 kW microturbine-based CHP system, fueled by natural gas, provides all of the computer and office lighting electric loads. In addition, thermal energy is captured and used for space cooling through the use of absorption chillers. During Superstorm Sandy, the power to the building and surrounding area was out for over two days; however, the data center was able to remain fully operational. No staff were at the building when the power went out; however, the automatic switch system transferred the data center load to a UPS while the CHP system transferred into island mode. The automated transition process took about one minute to complete. More information on the Public Interest Data Center can be found in the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Fajardo Sports Complex (Renewable CHP)
The Rafael Hernandez airport in Aguadilla, Puerto Rico originally installed a 120 kW CHP system as part of Lufthana's operations. In the aftermath of Hurricane Maria, the CHP system was moved across the island to the city of Fajardo in order to provide emergency services for nearby residents. The CHP system is located at the Fajardo Sports Complex which serves as a refugee shelter and distribution center for local residents. The CHP system is fueled by local waste biomass resources, such as woody biomass, and is the first non-diesel power generation system in the region. The system has provided critical relief services and shelter for residents in the region. More information can be found at BusinessWire.
Salem Community College (CHP)
Salem Community College, in Carney's Point, New Jersey, installed a 300 kW CHP system in 2009 in order to reduce energy costs and increase power reliability for the campus. The CHP system was critical in providing heat and power for campus buildings, including an emergency relief shelter, during Hurricane Sandy in 2012. The American Red Cross operated a disaster relief shelter in Davidow Hall, which provided emergency shelter and disaster relief services to roughly 85 people during and after the storm. More information can be found in the EPA's Guide to Using Combined Heat and Power for Enhancing Reliability and Resiliency in Buildings.
Margaritaville Vacation Club - Wyndham St. Thomas (CHP)
The Margaritaville Vacation Club in St. Thomas, U.S. Virgin Islands, was able to remain open during and after Hurricanes Irma and Maria because of the onsite power provided by the 1.8 MW CHP system. The Margaritvaville resort was able to power up its CHP system within hours after Hurricane Irma, and provide critical power to guests and emergency services to others on the island. The CHP system remains operational and the resort continues to provide power and water to those in need. More information can be found in a Capstone Microturbine press release about the 1.8 MW hotel CHP system.
Sikorsky Aircraft (CHP + Solar)
Sikorsky Aircraft Corporation, an aircraft manufacturer based in Stratford, Connecticut, installed a 10.7 MW gas turbine CHP system in 2011 to align with corporate sustainability goals. The CHP system provides the 2,000,000 square foot manufacturing facility with 84% of its electric and 85% of its thermal needs. Due to the reliability of the CHP system, the facility did not experience any interruptions during Superstorm Sandy, and was able to sustain normal operation during storm and aftermath. The facility also provided helicopter transport services for disaster relief personnel and supplies, and the manufacturing campus was opened as a place of refuge (meals, showers, phone charging) for the 6,650 employees and their families. Sikorsky has also deployed a number of other renewable energy and energy efficiency strategies, including installing 250 rooftop solar PV panels that produce roughly 106,250 kWh per year. More information can be found in the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Pfizer – Andover, MA - Pharmaceuticals (CHP)
In 1999, Pfizer installed a CHP system at their biotechnology campus in Andover, MA. The 10 MW natural gas-fueled turbine system provides electricity and thermal energy to the campus 24/7. The 70-acre site, seven-building campus houses some of the company’s R&D and manufacturing facilities, which require electricity and steam at all times. In order to provide a reliable power source, Pfizer turned to a CHP system that provides electricity, heat, and steam to the manufacturing campus. The system was designed so that Pfizer can temporarily separate from the grid in instances of anticipated outage. The CHP system also allows Pfizer to meet its sustainability goals and to significantly reduce its energy costs. More information can be found in DOE’s CHP project profile, Pfizer - Andover, and the Oak Ridge National Laboratory report Combined Heat and Power: Enabling Resilient Energy Infrastructure for Critical Facilities.
Community Microgrid - Fairfield, CT (CHP + Solar)
The town of Fairfield, CT experienced significant energy outages during Superstorm Sandy, and decided to invest in a community microgrid in order to improve the resilience of critical facilities. The microgrid consists of a 300 kW natural gas-fired generator, 47 kW of solar PV, and a 60 kW natural gas-fired reciprocating engine as the microgrid anchor. The microgrid serves the fire station, police station, an emergency communications center, a public shelter, and a cell phone tower. It has the ability to isolate from the electric grid in case of an outage event, and will greatly improve the resilience of the connected facilities during future weather and emergency events.
Utility Microgrid - Sacramento Municipal Utility District (SMUD) (CHP + Solar + Storage)
The Sacramento Municipal Utility District (SMUD) is a public utility that provides electricity to Sacramento County, California. SMUD commissioned its microgrid project in 2012 at the corporate headquarters campus in order to demonstrate real world microgrid operation and integration of different resources and technologies. A 300 kW CHP system serves as the microgrid anchor, and also provides heating and cooling to the campus buildings through a 128 ton absorption chiller and chilled water storage. The microgrid also incorporates 10 kW of solar PV, which works in tandem with the CHP system through a number of smart inverters and the microgrid controller. The project not only demonstrates how microgrids can efficiently incorporate different generation technologies, but also increase power quality and reliability and interconnect with the bulk power system.