One step closer to radical energy reduction in hospitals
Image courtesy of NBBJ
It's no surprise that fundamental shifts are taking place in the U.S. healthcare system. But some of the more significant changes in the coming years could have little to do with congressional reform. The pursuit of America's first net-zero hospital is one such example of an idea that has the potential to transform the healthcare industry.
Over the last several years, healthcare executives have become more willing to invest in energy reduction-inspired by the prospect of a facility that increases patient care, reduces annual energy costs, and eventually produces its own energy. In fact, energy reduction is proven to be one of the least expensive and easiest ways to immediately cut hospital operating costs.
A recent study by the University of Washington's Integrated Design Lab (IDL), NBBJ, TBD Consultants, and Solarc Architecture and Engineering, offers the next iteration in the plan to achieve the first net-zero hospital and make energy efficiency in hospitals affordable and worthwhile. The study shows how hospitals can reduce energy use by 60% at little or no additional capital cost. This report is the first time the cost of construction has been evaluated with design solutions, resulting in a clear understanding of how certain decisions will affect both energy efficiency and the bottom line. These strategies have also been vetted via hospital owners and facility managers to verify practicality and ease of maintenance.
By applying the study's architectural strategies and energy performance options, a new medium-sized hospital in Seattle could save more than $700,000 in annual energy expenses. In addition, implementing these strategies has the potential to improve staff recruitment and retention by creating a healthier, more pleasant facility in which to work and receive care.
Striking a major chord within the industry, the research caught the attention of the U.S. Department of Energy, which awarded the team a $1.2-million grant to extend its Pacific Northwest climate and cost-based model to a nationwide scope. Now armed with this new grant, IDL's core research team can empirically run these numbers for five additional cities and climate zones to see how a 60% reduction can be achieved in each region and at what cost.
Hospitals are the second most energy-intensive building type in the United States, consuming 4% of domestic energy use. There is also evidence that the health sector's energy use and resulting toxic emissions actually undermine the health of the communities the sector is meant to serve. On the basis of estimates by the United States Environmental Protection Agency (EPA), the U.S. health sector's 73 billion kWh “conventional” electricity use adds more than $600 million per year in health costs-including increases in asthma, respiratory illness, and hospital emergency department visits.1 If hospitals can slice their energy use by more than half, such a major achievement could significantly improve a hospital's bottom line, and have the added bonus of creating healthier communities.
The research project began in 2007 when the IDL secured funding from the BetterBricks program, an energy-efficiency initiative of the nonprofit Northwest Energy Efficiency Alliance (NEEA). Then, with collaboration from NBBJ, Solarc, TBD, Cameron MacAllister Group, Mahlum, and Mortenson Construction, the team sought to create a fully integrated, energy-efficient hospital design guide for the industry, keeping a close eye on indoor environmental quality and patient, family, and staff comfort.
The research team was inspired by Scandinavian healthcare facilities, which are world-renowned for very low energy use and excellent indoor environmental quality. They considered whether it was possible, under the U.S. healthcare model and code regulations, to build a radically energy-efficient hospital, and estimate how much it would cost.
Aligning itself with the 2030 Challenge and its current 60% reduction goal for new buildings (built between 2010 and 2015), they set the goal to reduce the energy use index of a typical hospital in the Pacific Northwest from 270 KBtu/SF to 100 KBtu/SF per year. The team then rolled up its sleeves and began discussing and evaluating various design strategies to achieve their objective.
With this goal in mind, the research team embarked upon an intense, three-year process of energy simulations, iterative hourly load testing, prototyping, cost analysis, and peer review. The result confirms that integrated energy-reduction solutions could indeed cut the hospital's total energy use by 60%, requiring no more than a 3% capital investment-most likely less than 2%-with a return on investment (ROI) accruing in fewer than five years. In other regions, ROI is likely to occur in a shorter time frame as these statistics are based upon Seattle's relatively low utility rates.
As modeled in the study, and to be further explored in the American Recovery and Reinvestment Act/DOE-funded extension of this research, the following is an example of a grouping of strategies proven to achieve significant energy savings when integrated together:
Increased daylighting - For better indoor environmental quality and decreased electric lighting use.
Better solar control - To minimize peak cooling loads and increase thermal comfort.
High-performance building envelope - To balance heat loss and radiant comfort with thermal performance.
Decentralized, decoupled systems - Separating the thermal conditioning from the ventilation air for better efficiencies.
Optimized heat recovery - Harvesting waste heat from the HVAC systems.
Advanced HVAC and lighting controls - Variable and shut off based upon occupancy.
Ground Source Heat Pump - Thermal balance of heating and cooling utilizes the natural thermal capacity of the ground.
While many of these concepts require departures from standard design and operations practices in hospitals, they are not necessarily new design ideas-just new to hospital design. What makes the strategies novel is the way they are bundled together using an integrated design process.
Drilling down to the different energy-reduction strategies, it seems intuitive to attack the largest energy consumer first-heating. However, in this study, cooling was the initial target because significant downstream energy and cost advantages of a redefined cooling system could be realized. Other strategies include: reducing use of air to transport heating and cooling and replacing it with fluid transport; using water to carry energy; and utilizing decentralized systems such as radiant panels, chilled beams, and fan coil units to deliver thermal tempering.
By decoupling cooling from ventilation air, reducing solar load, and employing decentralized systems, the entire ducting system was reduced in size and complexity, creating more room for systems integration above the ceiling. With additional overhead space, owners save up-front costs on building height and flexibility is built-in for future renovations. These strategies help create a balanced need for cooling and heating-opening the opportunity to employ an energy-saving ground source heat pump system.
Case in point
The research team is eager to fully apply the energy reduction model to a “live” hospital project. However, there are several new Pacific Northwest hospital projects implementing a subset of the study's strategies. These facilities include the University of Washington Medical Center (UWMC) in Seattle with the design of its new, eight-story, 273,000-square-foot Montlake Tower expansion project.
Ultimately, the UWMC will beat Seattle's baseline energy use code by 30%, and the national baseline code-ASHRAE 90.1 -by 33%. This will
essentially return $200,000 every year to its bottom line. The strategies will more than likely be achieved at no additional cost to the facility with help from some utility incentives. In this case, UWMC achieved utility buy-in by integrating the utility provider into the process early on.
In particular, the overall grouping of strategies used for the UWMC include daylight and solar control, optimized air supply, heat recovery chillers, and reduced lighting. In addition, a cool roof reduces heat build-up. Toxin-free, recycled, and locally sourced materials were selected where possible; rubber flooring was specified in patient areas to reduce joint stress; and low-flow plumbing fixtures were installed.
Research partner NBBJ recently surveyed its large, nationwide healthcare portfolio and discovered that by having applied some of the study's strategies to the 5.7 million square feet of hospital space currently in design, hospital owners will save $4 million in annual energy costs when their buildings come on line. When one extrapolates those savings across all new U.S. hospitals in design, a picture of the profound impact energy reduction can have on the operating costs for U.S. healthcare begins to come into focus. In addition, significantly improving indoor environmental quality creates an atmosphere that is more conducive to healing and reduces medical errors and occupational stress.
The study was recently presented at CleanMed, an annual conference representing members of the healthcare and building industries. Conference attendees responded enthusiastically to the research, with many looking to implement the strategies into their own facilities.
While the prospect of saving 60% in energy costs is quite an attention grabber, the real excitement from the healthcare industry has come from the rigorous, “real time” costing data analysis that accompanies the energy saving strategies.
In addition, a number of vetting sessions with hospital owners, local utilities, architects, and M/E engineers has added a high level of credibility and yielded some productive objective feedback that has guided the final results of the study.
“Physicians get the connection between the environment and health. Doctors want to work in facilities that are achieving these kinds of energy and health performance goals,” states Geoffrey Glass, director of facility and technology services at Providence St. Peter Hospital in Olympia, Washington, and one of the participants in the vetting sessions. “This research study sets specific, cost-effective, and achievable design principles for successfully reducing operational costs and carbon footprints. This report should be required reading for anyone planning to build or renovate a hospital in the future.”
Similarly, a recent Johnson Controls’ Institute for Building Efficiency/American Society for Healthcare Engineering/International Facility Management Association study revealed that 58% of North American healthcare facilities ranked energy management as very or extremely important to their organization, and 62% plan on making capital investments in energy efficiency over the next 12 months.
The research group has already started the next phase of research with the aim of moving America's hospitals closer to net-zero. The group held its kick-off brainstorming session in October and anticipates the first round of results will be published in early 2012.
Meanwhile, research partners continue to work with clients to implement part or all of the study's strategies. NBBJ has just begun work on an 850,000-square-foot acute care hospital that is slated to achieve a 60% reduction when it opens in 2015.
Hospitals are an essential community resource and this study offers a way to keep these critical enterprises viable by cutting bottom line costs, creating healthier communities, and improving patient and staff environments. It's a win-win scenario for patients, their providers, and our planet.
Duncan Griffin, LEED AP, is an architect and senior associate at NBBJ, specializing in healthcare facility design. He can be reached at DGriffin@nbbj.com.
Heather Burpee is the lead health design researcher at the University of Washington's Integrated Design Lab. She can be reached at email@example.com.
- Health impacts and costs based on United States Environmental Protection Agency Clean Air Interstate Rule data (http://epa.gov/oar/interstateairquality/index.html, accessed 20 April 2009) using the Practice Greenhealth Energy Impact Calculator (www.eichealth.org, accessed 20 April 2009)
Healthcare Design 2010 December;10(12):10-13