Energy efficiency in hospitals
Hospitals and laboratories emit 4.4 percent of the world’s greenhouse gas emissions, according to a September 2019 report “Health Care’s Climate Footprint,” from Arup and Health Care Without Harm (HCWH).
Yet in much of Goldman Copeland Consulting Engineers’ work with 18 hospitals, we find that they have extraordinary potential for improved energy efficiency. The opportunity stems from several common characteristics of hospitals, including a tendency toward ad hoc infrastructure upgrades and a need for a wide range of room temperatures, which can be quite wasteful of energy unless well-managed.
Realizing that potential can reduce a hospital’s carbon footprint, demonstrate commitment to energy savings, play a significant role in slowing the impact of climate change, and reduce energy costs.
In addition, governments or local utilities may offer financial incentives, depending on the location and the energy systems involved.
Benefits of centralizing energy infrastructure
Some of the opportunity arises from the fact that hospitals typically expand in size by building additions. In many cases, this means additions on top of additions.
The energy infrastructure grows accordingly, gradually departing from the original centralized plans and leading to unplanned systems that often perform inefficiently and may fail to meet the needs of the space.
Hospitals can, therefore, identify savings through energy audits that look at the whole medical complex and focus on solutions that return the plant operations to a centralized concept and thus allow optimal system performance.
On one hospital project, for instance, we were able to increase the size of a main chilled-water distribution line that had limited the building’s ability to adequately provide air conditioning to more distant air-handling units.
The increased distribution improved chiller performance and occupant comfort. It also allowed the building to reduce usage of relatively inefficient supplemental units that had been operating to make up the difference.
Improving hospital heating/cooling systems
More opportunity can be found in the fact that hospitals have a constant demand for both heating and cooling simultaneously. This makes it possible to take heat that would otherwise be rejected into the atmosphere and use it for heating purposes.
Certain healthcare spaces, especially operating rooms and other areas with high-density technological equipment, need colder and dryer air than the rest of the hospital, which then needs increased heat to be comfortable. Various energy-recovery solutions can off-set or eliminate the resulting inefficiencies.
Improved energy efficiency can be achieved by balancing those various—often competing—needs. For example, combined heating/cooling heat pumps perform both functions simultaneously, creating hot water with cold water and vice versa.
This set-up eliminates the need for two separate systems and can cut equipment costs, while also reducing energy costs and increasing occupancy comfort. These systems can be incorporated into new designs or retrofitted as an energy conservation measure.
Changes in regulatory standards can also create opportunity. Many existing HVAC systems, for instance, predate amendments to healthcare design guidelines that now allow systems to be turned down during unoccupied periods. Rather than requiring 12, 15, or 20 air changes per hour on a continuous basis, hospitals can turn down airflows while the room is unoccupied as long as humidity levels and room pressurizations are maintained.
Consider geothermal for healthcare
The need to balance simultaneous heating and cooling requirements—as well as the size of most medical campuses—makes healthcare facilities good candidates for taking advantage of geothermal ground source energy. This underutilized renewable energy resource can generate energy and financial savings in the long run.
Geothermal ground source energy is thermal energy extracted or stored in the ground subsurface. That energy can be accessed from a lot of areas to provide efficient heating and cooling for nearby buildings. Its great benefit is that the stored thermal energy is naturally available in the ground. Electric energy is needed to access it but at a reduced level that helps make the electric grid more sustainable.
While the geothermal ground source energy is free, there is a cost to extract and circulate it. There are also upfront expenses associated with installing the geothermal system.
The cost can best be justified when a new heating or cooling system is needed, with much of the cost recovered over time in reduced energy costs, lower carbon emissions, and longer equipment life cycles. Payback periods from these measures can be in the range of 10 years, although they vary significantly depending upon the specific details of the project.
Incentives for energy-efficiency efforts
Healthcare systems should look for financial incentives from federal and often state governments or local utilities to cover the cost for energy audits, as well as geothermal ground source energy systems.
Both PSE&G and New Jersey Natural Gas, for instance, have robust programs of support for energy audits by hospitals in New Jersey. These organizations can also provide upfront financing for most related energy infrastructure improvements, with a sizeable portion of that amount forgiven over five years.
Healthcare’s role in reducing carbon emissions
At a time when cutting carbon emissions is a national and global priority, hospitals can play a crucial role. The strategies mentioned here can help facilities increase their own energy efficiency, save energy and money, and benefit the planet in the process.
Tristan Schwartzman is a principal and the director of energy services at Goldman Copeland Consulting Engineers (New York). He can be reached at tschwartzman@goldmancopeland.com. Jonah Allaben is a senior associate in energy services at Goldman Copeland Consulting Engineers. He can be reached at jallaben@goldmancopeland.com.
