Designing, retrofitting hospitals during COVID: Sustainability
While COVID-19 has changed many aspects in a health care facility, some things remain identical. Learn about energy efficiency and sustainability
- Luis Alvarez Colon, PE, Associate, Page, Austin, Texas
- Allison Graves, PE, Principal, RTM Engineering Consultants, Chicago
- Jeff Hankin, PE, LEED AP, Senior Principal, Stantec, San Diego
- Reed Paitich, PE, Associate, Wold Architects and Engineers, Saint Paul, Minn.
- Keith D. Prata, PE, LEED AP BD+C, Mechanical Department Manager, Bala Consulting Engineers, Boston
- Donald R. Stevens, CHFM, CHC, Director – Health Care Facilities, Lockwood Andrews & Newnam Inc. (LAN), Austin, Texas
What types of renewable or alternative energy systems have you recently specified to provide power?
Donald R. Stevens: LAN has designed and specified photovoltaic, compressed natural gas and combined heat and power plants for clients in recent years. In almost every case, the decision to implement an alternative energy system came down to simple economics driven by the commodity fuel markets. PV, in Texas for example, has a 7- to 10-year payback due to relatively low electric rates. California has much better economics due to their higher tariffs.
Smaller (2 to 3 megawatts), natural gas fired CHP has a similar payback due to the costs associated with the engine overhaul that comes due right about the time the system would have paid for itself. Larger plants, usually gas turbines, have a better payback if the client has the need for both electricity and heat for their processes. LAN has one client that uses these turbines to generate electricity for about 7,500 tons of chill water capacity and process steam for a health care campus. In short, a detailed investigation is required to match the alternative energy source to the demand to see if the economics work.
What level of performance are you being asked to achieve, such as WELL Building Standards, U.S. Green Building Council LEED certification, net zero energy, Passive House or other guidelines?
Reed Paitich: We recently designed a skilled nursing facility in Montevideo, Minn., that was required to meet the Minnesota Sustainable Building Energy Standard (based on the national Architecture 2030 program), which required a reduction in energy of 70% from a similar building’s average energy use. To meet the 70% energy reduction, the HVAC system design included a geothermal ground-coupled VRF system, with 100% outside air ventilation units. We also employed a 40-kilowatt photovoltaic solar system on the roof. We were able to meet the 70% energy reduction as well as reduce the summer electric peak demand by 39%.