Don Talend 2016-06-06 18:16:11
Increasing cost pressures on hospitals due to impacts of health care reform on reimbursements appear to be impacting their energy sources, according to some industry experts. Changes in the economic model and ever-growing demand for reliability and lower emissions mean that distributed generation has a bright future in this space. Hospital systems have generally become more efficient in recent years. They typically require about 215,000 BTU per square foot, compared with 250 BTU several years ago, and should become even more efficient in the coming years, says Daniel McGinn, director of secure power systems at Schneider Electric. More efficient HVAC systems have equipment such as high-efficiency centrifugal chillers, adds Jim Crouse, executive vice president, sales and marketing at Capstone Turbine. The load demand at a typical hospital has not increased in recent years, despite the use of increasingly high-tech patient care equipment, according to Crouse. “I’ve been doing this for more than 25 years, and it seems that the overall load profile is the same—what’s changed is where the power is going,” he says. McGinn notes one factor that sometimes affects load demand: outsourcing of some data center capacity to cloud networks or colocation facilities. A larger issue in the hospital space is in the need for high-availability power, interaction with an evolving grid infrastructure, and powering a more distributed hospital enterprise, McGinn adds. Ensuring Reliability Some hospitals that are reducing their reliance on the grid are doing so because of increasingly common natural disasters in the United States and around the world. “It’s made hospital administrators and operators of central plants more aware of the need to have power continuity,” says Crouse. “To me, the other thing that has raised awareness is the microgrid/smart metering/smart grid movement that’s starting to take effect in the industry. Hospitals are looking at the ability to combine onsite generation—whether it’s diesel standby, natural gas CHP [combined heat and power], solar, or small-scale wind equipment—and put in smart devices.” The objective is to provide power to a facility for an extended period of time, he says. More uninterruptible power supply (UPS) systems are used in hospitals to protect high-tech equipment, Crouse adds. Besides a complete loss of utility power, McGinn says many other types of power disturbances can interfere with hospital functions and even damage equipment. Significantly, systems that depend entirely upon grid power are susceptible to interruptions within the facility that have nothing to do with the incoming power, e.g., a feeder breaker trip or protective relay function. McGinn refers to Article 517 of the National Electrical Code (NEC), which requires hospitals to provide an Essential Electrical System (EES). The code segregates EES circuits into three categories: Life Safety, Critical Branch, and Equipment. The code also requires a physical segregation of these circuit types. Life Safety and Critical Branch loads are also considered emergency power, which requires that the system allow for no more than 10 seconds of power loss. The code does not prescribe which Critical Branch or Equipment functions are to be powered by the EES—that is usually determined by the hospital’s risk assessment and coordinated with the local Authority Having Jurisdiction (AHJ). Many large investments in EES equipment are rooted in the hospital risk assessment, which should be done in concert with the AHJ, the consulting engineer and the hospital’s underwriter, McGinn suggests. Hospital executives should try to stay current with trends and what is “reasonable and customary” for functions that should be covered by the EES, he adds. Within existing facilities, investments are more often made in systems that operate closer to functions, e.g., a new piece of equipment that warrants a UPS to provide continuous power. Providing protection close to the load protects against disturbances downstream of the utility feed and central EES systems, e.g., a breaker trip. McGinn also recommends considering local UPS applications in concert with ground-isolating power distribution, which offers local UPS-backed power on a smaller footprint, and away from patients. A Good Fit for Cogeneration Hospitals are good applications for CHP because of their steady, 24-hour load profile that demands hot water or steam, and chilled water throughout the year, according to Crouse. He adds that, in recent years, two demand drivers have emerged for CHP in this application. The first is resiliency or security. A localized power source provides the necessary electricity as well as hot water, and in some cases chilled water, with the latter dependent on the size of the hospital and existing infrastructure. “If it has a central plant with boilers and chillers, it’s easier to install a chilled/hot water CHP system,” says Crouse. “If it has refrigeration-based cooling or is decentralized from a hot water or chilled water perspective, it becomes a little more difficult to integrate CHP.” The other demand driver that favors CHP is environmental stewardship. Crouse advises hospital executives to ensure that the engineering firm rightsizes CHP equipment to make implementation successful. “If the electrical thermal load profile of the facility only justifies one megawatt but the electrical load is three megawatts, you shouldn’t be sold three megawatts because you won’t get the return on investment. You’re not able to use all of the thermal energy, and vice versa if you oversize for thermal and the extra electrical energy becomes worthless.” Big Apple Reliability The Memorial Sloan Kettering (MSK) Cancer Center in New York City is a slightly different case. MSK is having a Capstone C1000 microturbine unit installed to provide 1 MW of power hot air, hot water, and chilled water for a combined cooling, heat, and power (CCHP) system on its campus on Manhattan’s Upper East Side. The system, which should be commissioned in 2017, is intended to reduce demand from the grid during peak hours and cut the overall energy purchased from the grid. The microturbine will provide both primary power and additional backup power in the event of a utility blackout. The system is expected to save the owner at least $1 million in annual operating costs. The microturbine will operate in “dual mode,” allowing the facility to easily transition from continuous power mode to standby power mode. The unit will be the primary power source and will always be available as the emergency backup power source. According to Cory Glick, president of RSP Systems, the Capstone distributor for New York and Connecticut, the decision had been made to design a cogeneration system to ensure emergency power during the development process starting in early 2014—it was just a question of which technology would be used. Glick points out that the MSK leadership was seeking a reliable backup power configuration, given the lessons of Hurricane Sandy in October 2012. About 200 patients had to be evacuated from NYU Langone Medical Center in the wake of Sandy because several of that facility’s oil-fired generators failed when the basement flooded. With a relatively compact footprint of 38 feet by 19 feet, 6 inches, the natural gas-powered microturbine, equipped with five 200-kW engines, will be mounted on the new building’s roof, eliminating potential vulnerability to flooding, Glick notes. He adds that the microturbine is not subject to the challenges inherent to supplying oil to the island of Manhattan, and there is no need for oil to be brought into a facility intended to be sterile or for disposal of used oil. Even the equipment itself does not require petroleum lubrication: it runs on air bearings. Fuel Cells Have Great Potential A less established technology for locally powering hospitals, but one that nonetheless has tremendous potential, is fuel cells. Professor Scott Samuelsen, Ph.D., director of the National Fuel Cell Research Center at the University of California, Irvine, says that fuel cells will suit hospitals in the future, just as they are currently used in wastewater treatment plants. Both applications need to stay in operation in the event that the grid goes down, he points out, and fuel cells have proven to be a reliable, low-emissions technology in many stationary applications. Fuel cells electrochemically convert any of several fuel sources into electricity and heat in a highly efficient process that emits virtually no pollutants due to the absence of combustion. As at many wastewater treatment plants, fuel cells are becoming the go-to local power source over diesel gensets. “We already have the market for hospitals, but it hasn’t evolved out of the embryo stage to the adolescent stage,” says Samuelsen. “But it has shown signs of moving in that direction.” Samuelsen acknowledges that the marketplace is not yet fully aware of the benefits of fuel cell technology. A major reason for this is the fact that this technology may seem too good to be true, he contends. Specifying engineers and facilities staffs that are used to technologies that run on combustion, such as gas turbines and reciprocating engines, tend to be skeptical that fuel cells can actually produce electricity without producing significant noise. And, “When you add to it the virtues of virtually no emissions, the suspicion goes up even higher, because everything we do today that produces combustion produces emissions, so that’s a difficult barrier to overcome,” he says. Another barrier to acceptance is educating the market that heat energy can be converted into water-chilling energy—and that fuel cells can serve as the fuel source. “Intuitively, that does not make sense,” says Samuelsen. “We remind the market of the old gas refrigerators where you’d convert heat from the flame of the natural gas burner into refrigeration, and the particular technology for that is absorption chilling. It does take time to show how this heat that would otherwise go up into the atmosphere and be lost forever can be put into the absorption chiller box and out comes chilled water.” Samuelsen points out several characteristics of hospitals for which fuel cells are well-suited. They have a similar load demand to that of wastewater treatment plants, another type of facility for which reliable power is of critical importance. Fuel cells’ ability to operate in baseload align nicely with hospitals’ constant load demand, and fuel cells’ load-following capability will only improve in the future. Fuel cells currently favor constant operation without changing power output, and they also have cooling output capability. Another salient attribute of hospitals is their need to instantaneously transition to backup power generation. Samuelsen describes diesel gensets as “stranded assets” until they are used and, when they are put into service, produce emissions levels that many progressive air quality districts are no longer permitting. Fuel cells serve as a viable alternative that produces power at all times with greater intensity than diesel gensets traditionally have, provide a constant reduction in operating costs to a hospital, and do so more reliably, according to Samuelsen. A project that was recently commissioned at the University of California Irvine (UCI) Medical Center helps to build the business case for fuel cells in the hospital market. CCHP Project Showcases Fuel Cells In January 2016, a 1.4-MW FuelCell Energy Direct FuelCell power plant was commissioned to provide both electricity and usable heat to the UCI Medical Center after about a year and a half of development work. The power plant is configured for CCHP so that the same unit of fuel generates both ultra-clean power and usable high-quality heat that will be used for heating water and converting some of the heat into cooling for air conditioning. The system, powered by natural gas, could also be powered by biogas. FuelCell Energy installed, and is operating and maintaining, the plant and medical center—a campus with a 412-bed acute care facility—purchasing the electricity and heat under a multi-year power purchase agreement. The agreement allows the owner to receive clean, quiet, and inexpensive onsite power without the need for a capital investment. The power plant delivers locally generated, continuous baseload power. It will generate about 30% of the facility’s power, and the heat produced will be used to partially fulfill the medical center’s hot water requirements and be directed to a direct-exhaust absorption chiller that will produce 200 tons of cooling for office building air conditioning. Due to its low carbon and nearly complete absence of criteria pollutants, the power plant is exempt from air permitting under the California South Coast Air Quality Management District Rule 219. The plant’s low-emissions attribute accelerated the project development process. Samuelsen notes that the project aligns with one of the goals of the National Fuel Cell Research Center (NFCRC), which was established in 1998 at UCI by the US Department of Energy (DOE) and the California Energy Commission, accelerating the development and deployment of fuel cell technologies. The California Energy Commission, South Coast Air Quality Management District, and Southern California Gas Company invested in the project. According to Samuelsen, this project addresses the development goal by integrating the fuel cell and an absorption chiller so that heat that would otherwise get exhausted from the fuel cell is used to chill water for air conditioning. The project addresses deployment by educating and providing incentives for the market to consider this technology in the future. Its lower cost and lower emissions of criteria pollutants preserves urban area air quality and reduces greenhouse gases. Compared to the electric grid, the fuel cell installation is expected to prevent the emission of 28 tons of nitrogen oxide, 64 tons of sulfur dioxide, 3,000 pounds of particulate matter and more than 7,000 tons of carbon dioxide. Back in 2010, the NFCRC submitted a proposal to the California Energy Commission to complete a fuel cell demonstration project, conduct research in the process of developing and optimizing the design, identify a location, and design a facility to serve as an educational showcase to address questions about the technology. The NFCRC worked with the medical center to establish a power purchase agreement to support installation of the power plant and on the facility construction and commissioning as the co-project manager along with the medical center’s facilities staff. The medical center had evaluated different CHP technologies, but did not include cooling until the NFCRC got involved, Samuelsen recalls. “In order to enhance the reliable provision of electricity to the hospital and at the same time meet the very restrictive environmental regulations in southern California, the medical center placed a high priority on fuel cells,” says Samuelsen. “They were the final piece of the puzzle that fit. In California, we have had fuel cell installations at other hospitals that have increased the confidence of entities such as the UCI Medical Center in fuel cell technology. The only thing that’s different about this installation is the capture of heat for 200 tons of cooling.” Although there are no current plans to supplement the fuel cell power plant with solar power, Samuelsen says he is seeing more and more of those combinations. He points out that solar power is faced with a couple of challenges. One is its diurnal nature, i.e., it only generates energy when the sun is out. The other is intermittency: When clouds block out sunlight, it suddenly cuts power, and another power source must compensate. Fuel cell is a clean technology that complements solar in a steady fashion, whether in distributed generation, or as a main fuel source, Samuelsen says. He predicts that the UCI Medical Center project will yield valuable fuel cell performance information that will support future technology development. “We will monitor the data closely from the project—for example, efficiency and emissions to inform the models that we developed in the program that describe the performance of the technology and will help us improve the system performance in the future.” To showcase the project, the NFCRC set up a conference room with a flat-screen monitor playing a presentation that describes how the system works and another that displays its performance: emissions, efficiency, and amount of cooling. “One of the objectives of this installation is to have the market go up and kick the tires,” says Samuelsen. The Future What does the future hold for onsite hospital power generation? Intelligent grid systems and mass energy storage systems that leverage solar and other local energy sources will be a big part of that future. Microgrids will no doubt play a big part, too. The DOE covers several successful projects and answers questions about microgrids at www.energy.gov/articles/how-microgrids-work. Samuelsen notes that the efficiency and reliability of microgrids is receiving a lot of attention as the technology evolves. In March, the Advanced Power and Energy Program (APEP) at UCI hosted the International Colloquium on Environmentally Preferred Advanced Generation series, which alternates between two clean energy topics every year: microgrids (the 2016 focus) and grid energy innovation. Also, Samuelsen reports that APEP has a DOE contract to develop a microgrid controller, and the UCI Medical Center is one of the partners on the project. Crouse says that the trend is moving away from using a single technology, toward a combination of technologies to meet the needs of a given facility, whether the needs relate to financial, backup power, environmental, or carbon reduction. Capstone looks at more than just CHP or backup power generation and works with partners such as solar developers, energy storage companies, and microgrid technology companies to devise customized solutions as well. “That’s one of the challenges with CHP in general—two hospitals aren’t necessarily going to have similar needs because their operations might be slightly different or they might be in different climate zones,” says Crouse. “The needs of a hospital might center around emissions or environmental priorities, but also noise and vibration. We see a lot of interest in our technology because we have no noise or vibration. So, the cost of trying to integrate a new design into an existing facility is sometimes much lower because of the lower overall environmental impact of offsite generation with a product that has very low noise and zero vibration.” BE Don Talend specializes in covering sustainability, technology, and innovation.
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