Design in a Time of Uncertainty
By Rives Taylor, Principal, Global Resilience Research Lead
HARC researchers now assessing obstacles to greater use of combined heat and power (CHP) say hospitals and campuses offer particular promise for their expansion in Texas.
CHP systems (and complementary energy-efficiency features) that are already in place at some of Texas’ leading medical and educational institutions illustrate the benefits that CHP and efficiency proponents routinely cite.
Thermal Energy Corporation (TECO), Houston
TECO supplies heating and cooling to 18 institutions with 45 buildings that comprise about three-fourths of Houston’s Texas Medical Center. A $377-million project with a 48-megawatt CHP plant and associated elements is projected to save about $200 million in energy costs by 2025. In addition, the natural-gas-fired plant’s greater efficiency is expected to eliminate about 302 tons per year in emissions of smog-forming nitrogen oxides and 305,000 tons of carbon dioxide, the principal human-produced greenhouse gas. These pollution reductions equate to the emission reduction that would be achieved by taking 52,000 cars off the road, according to the U.S. Department of Energy.
Methodist Hospital, Houston
Houston’s Methodist Hospital added a 4.6-megawatt CHP unit to accommodate the steam demand of a new research building that opened in late 2010. According to a HARC report on the project, key motivations included energy security, reliability and emergency preparedness. “With the installation of the CHP, the hospital ensured that it had the ability to generate electricity, provide chilled water and steam, even during long term electrical utility outages that might be caused by natural disasters (such as hurricanes),” the report added. With a catalytic scrubber, the project ensured “significantly lower” emissions of nitrogen oxides, because higher-emission steam boilers could be operated less often.
University of Texas at Austin
When it comes to CHP, the University of Texas at Austin was an early adopter. The campus CHP plant was first established in 1929, before a municipal electricity grid could provide power there. Expanding to meet the needs of a growing campus over the decades since, the CHP plant now has a 43-megawatt unit and a 34-megawatt unit, according to a HARC report. Key additions to the system since 2004 have achieved “continuous efficiency gains, savings and greenhouse-gas reductions,” the report added. As a result, emissions of carbon dioxide have been cut by 85,850 tons per year, with costs “strongly indicating a synergy between favorable economics and the associated environmental benefits.”
University of Texas School of Nursing, Houston
The University of School of Nursing in Houston’s Texas Medical Center is part of the UT Health Science Center, one of TECO’s customers. Besides participating in the benefits of TECO’s CHP project, the School of Nursing’s building has energy-efficiency and other environmental-impact-reducing design features that earned a number of awards, including recognition by the American Institute of Architects as one of the nation’s “Top 10 Green Projects” in 2006. At that time, the school said the energy-saving features produced annual cost savings of nearly $77,000, with analyses showing the new building would use 80 percent less energy per square foot than the adjacent UT School of Public Health, constructed 25 years before.