Superstorm Sandy made it abundantly clear just how vulnerable critical facilities are to flooding and power outages and thus the importance of creating microgrids.
One important way to build a microgrid - distributed energy that can operate outside the electric grid - is to use Combined Heat & Power (CHP), which supplies both heat and electricity, by capturing waste heat.
This is especially crucial for hospitals and medical centers, five of which are being honored by the US Environmental Protection Agency (EPA) for their use of extremely efficient Energy Star-rated CHP systems.
The honorees are:
- Medical Area Total Energy Plant, Boston, Mass.
- Montefiore Medical Center, New York, N.Y.
- New York Presbyterian Hospital/Weill Cornell Medical Center, New York, N.Y.
- New York University, New York, N.Y.
- Texas A&M University, College Station, Texas
For hospitals, CHP provides reliable uninterrupted patient care and protects vital assets such as medical research facilities, diagnostic labs and pharmaceutical supplies.
For universities, it provides uninterrupted electricity, heat, and cooling for dormitories and classrooms, and protects data centers and research activities that are vulnerable to losses of air conditioning and electricity.
The CHP systems at these institutions have operating efficiencies ranging from 69-75%, much higher than the efficiency of separate electricity and thermal energy production, which is typically less than 50%.
NewYork-Presbyterian Hospital's CHP system, for example, generates 7.5 megawatts (MW) of electricity and up to 70,000 pounds of steam per hour. The steam is used for space heating and hot water and the system can supply 100% of electricity demand. And is saves the hospital about $5 million a year on energy costs.
Thanks to New York University's CHP system, the campus kept operating even after Hurricane Sandy - the rest of lower Manhattan was without power for several days. It can generate 12.9 MW of energy, supplying 37 campus buildings.
In August, President Obama issued an executive order that calls for 40 gigawatts of new CHP capacity in the US industrial sector by 2020, a 50% increase from today's levels. Interest in CHP on the residential level is also growing.
Much of CHP is currently powered by natural gas, but the Oregon Institute of Technology is the first university to use geothermal as the power source and a California water utility runs it on biogas.
Here is EPA's CHP website: