Designing health care facilities and medical campuses: Sustainable buildings and energy efficiency
Hospitals, clinics, and similar facilities are among the most demanding an engineer can tackle—the technology is evolving rapidly, hospital managers are increasingly budget-conscious, and assist in saving lives. Here, sustainability and energy efficiency design trends are explained for these building types.
- Andrew Flanagan, PE, GPD, LEED AP, Associate, Senior Plumbing Engineer, Interface Engineering, Portland, Ore.
- Mikhail Fuks, PE, HFDP, Engineering Group Leader, P2S Inc., Long Beach, Calif.
- Gary Hamilton, PE, LEED AP, CxA, EDAC, SASHE, Senior Vice President, WSP, Arlington, Va.
- Alex Harwell, Client Manager/Project Manager, Dewberry, Raleigh, N.C.
- Ted Hood, Senior Project Manager, TLC Engineering for Architecture, Brentwood, Tenn.
- George P. Isherwood, PE, Vice President, Peter Basso Associates Inc., Troy, Mich.
- Jeremy Jones, PE, LEED AP, EDAC, Healthcare Market Leader, Affiliated Engineers Inc., Chapel Hill, N.C.
- Brian Kannady, PE, Principal, ME Engineers, Golden, Colo.
CSE: What unusual systems or features are owners requesting to make their facilities more efficient?
Fuks: Owners are requesting more integration between building systems outside of HVAC and lighting. Energy-conscience owners are looking for building envelope systems and overall building orientation to be developed with energy efficiency top of mind. Also, many of the low-voltage systems in a building are starting to be integrated including security, elevators, paging, nurse call, audio/video, etc.
Kannady: One health care system we have worked with has been very progressive with the integration of HVAC and electrical systems into the campus BAS, to implement a building-analytics platform for disclosure reporting, compliance reporting, and energy management. The challenge has been in coordinating these requirements and systems across multiple facilities, in several towns, with new and existing facilities.
Jones: Monitoring, metering, and trending. They don’t “make” the facilities more efficient, but they “keep” them that way. It doesn’t take many errant setpoint changes post-occupancy to undo the best of design intentions. You can’t correct what you don’t have the ability to diagnose.
CSE: What types of sustainable features or concerns might you encounter for medical facilities that you wouldn’t on other projects?
Fuks: Water consumption and plug loads are much higher at medical facilities. Process equipment uses more water, and the need for water replenishment to void bacteria buildup requires make-up water to be added. Plug loads are increased due to larger medical equipment being plugged in for CT scans, MRIs, and other procedures.
Jones: Many sustainable strategies involve the recovery of energy from exhaust streams. Many hospital exhaust streams are contaminated by infectious patients and must be carefully handled from an energy-recovery standpoint to avoid cross-contamination.
CSE: What types of renewable or alternative energy systems have you recently specified to provide power? This may include photovoltaics, wind turbines, etc. Describe the challenges and solutions.
Jones: In my opinion, PV power generation has tremendous potential for the future, but it has not quite crossed the threshold of quick payback that would make for easy inclusion in projects. Like LED lighting already has, PV technology costs are moving in the right direction and will get there, but today, implementing this technology takes an owner that is especially committed, has major incentives from a utility company, or is in a regulatory environment or has a mandated energy goal that requires it.
Fuks: Photovoltaic panels are always considered for mostly new construction, but there is often not enough available area to provide significant power generation. Parking structure projects are more ideal for PV, and we have seen success with connecting them into campus PV systems versus a specific building.
CSE: What are some of the challenges or issues when designing for water use in such facilities?
Fuks: Water use is high, and facilities are still trying to standardize the water efficiency of medical equipment, such as sterilizers, cart washers, and autoclaves. Also, there is a constant concern for patient health, and how to avoid hospital-acquired infections, so water filtration within a facility is important to avoid bacteria growth.
Flanagan: Water is used for myriad services within health care facilities. We use water to move and store energy, transport waste through the sanitary system, sterilize equipment, protect against fire, cook, clean, and consume. However, many facility managers do not understand that once the water has passed through the utility company’s meter, it becomes the facility’s asset and liability to manage. Large health care facilities may have miles of pipe, equating to thousands of gallons of water sitting or circulating throughout the various piping systems that are the responsibility of the facility to maintain healthy standards for the various services. Water- and energy-conservation measures conflict with best practices for maintaining healthy potable water. I’ve witnessed a client perform system flushes by opening up all faucets in an area of the building monthly to maintain the quality of water in pipes-this action was in direct response to low-flow fixtures reducing water velocity through the existing pipes and increasing length of stagnation in fixture run-outs-which has caused an increase in total water consumption. Piping systems and equipment need to be designed to allow appropriate testing, treatment, and maintenance of the already purchased water.
CSE: What level of performance are you being asked to achieve, such as WELL Building Standards, LEED certification, net-zero energy, Passive House, or other guidelines? Describe a project and its goals, identifying the geographic location of the building.
Fuks: LEED certification for health care facilities is becoming more common, and energy-conscious owners are already targeting net zero energy.
Jones: The most prevalent standard among my clients is the Energy Star rating. The idea of a direct comparison with a hospital’s peer institutions resonates with many decision-makers.
CSE: Are certain rooms within a hospital or other medical facility designed to be more efficient than others due to the purpose of the space? Give an example.
Jones: I would say that the inverse is true. Some health care spaces will be less efficient than others due to the purpose of the space. In most jurisdictions, an operating room requires 20 air changes to meet current codes. In most actual operating rooms, significantly fewer than 20 air changes would actually be required to meet the true cooling and heating loads. All of this air must be cooled, dried, then reheated. The same is true for patient rooms. I don’t believe there is very much science behind the industry’s 6-air-change standard. Energy efficiency gains could be achieved if more research was done regarding the direct correlation between air changes and patient outcomes, which could be used to substantiate reductions in prescriptive code requirements.