For many top-tier US universities, a robust district energy system is integral to their Climate Action Plan, providing a flexible platform to integrate multiple resources like renewable energy, combined heat & power (CHP) and thermal storage for a more a resilient, efficient and sustainable campus to support the core missions of research and education. Universities have long been leaders in reducing emissions through continuous investment in energy efficiency along with renewable energy projects like solar pv, biomass, landfill gas, earth-coupled heat pumps, and even lake water for district cooling. Because a district energy network aggregates the energy needs of dozens of buildings, it creates economies of scale that facilitate investment in energy technologies not otherwise feasible on a single-building basis. District energy infrastructure has made it possible for Harvard to meet its carbon reduction goals earlier than predicted, for UT Austin to use less fuel over the past 10 years despite a campus that has nearly doubled in size, and for Princeton to maintain continuous operations through a devastating event like Super Storm Sandy.
After many years of study, in 2000 Cornell University implemented an award-winning lake source district cooling project to exchange cold water from nearby deep Cayuga Lake for renewable air conditioning to 14 million sq ft of campus buildings, cutting operating costs by 87% and essentially exchanging a big electricity bill for a bond payment on this innovative $58 million investment. In their 2009 Climate Action Plan, Cornell pledged to further reduce carbon emissions to zero by 2035. The plan identified 5 key areas for reduction, with 42% of the savings from shifting to CHP from coal. Because using CHP provides economies of scale in a campus energy system, things like equipment upgrades, converting from coal to natural gas and biomass, and integrating renewable energy sources are more economically feasible. Just the construction of the CHP plant, which came online in 2010, cut Cornell’s carbon emissions by a total of approximately 75,000 tons by 2012, representing over 20% of the Ithaca Campus greenhouse gas footprint. The university also claims a host of other benefits from their CHP plant; “Improved energy efficiency; enhanced environmental protection; fuel flexibility; ease of operation and maintenance; reliability; comfort and convenience for customers; decreased life-cycle costs; decreased building capital costs; improved architectural design flexibility.”
For more information, please visit: Cornell University Initiatives: Combined Heat and Power; Cornell University Energy; Cornell Unveils its Climate Neutrality Plan; Cornell Lake Source Cooling
University of Texas at Austin
The University of Texas at Austin has earned the distinction among its peers as “the most efficient university utility in the U.S.” based on the stewardship and operation of a highly efficient campus district energy microgrid that includes 135 MW of on-site CHP generation, thermal energy storage, turbine inlet air cooling and advanced controls and energy management. Natural gas is the primary fuel used at UT Austin and the university acknowledges that while natural gas is considered one of the cleanest fossil fuels available, it is still a significant source of greenhouse gas emissions. However, the high efficiencies reached by their CHP facility (between 82 and 87% annually) means that producing energy for the campus with CHP has avoided the cumulative release of 862,000 tons of carbon dioxide since 1996, equivalent to taking nearly 164,630 cars off the road. UT Austin is so successful at efficiency optimization that their energy system “has helped the campus lower its CO2 emissions to 1977 levels, while the campus has grown by over 40 percent since then.” Meanwhile they also maintain reliability of 99.9998% which is crucial for supporting mission-critical research requiring uninterrupted energy in a hot, humid climate like Austin.
CHP has been the fundamental backbone to UT Austin’s success in reducing carbon emissions while nearly doubling the size of their campus, essentially supporting carbon-free growth over the past decade. Juan Ontiveros, Associate Vice President of Utilities, Energy & Facilities Management at UT summarizes it best, “We’ve been able to produce twice the amount of energy, for twice the amount of square footage, with the same amount of fuel, for a 10-year period. Everyone could do that— I’m not the only one. These are all proven technologies that you can implement right now.”
Carl J Eckhardt Combined Heating and Power Complex has dramatically reduced fuel consumption and improved efficiency while maintaining energy flows to a growing campus between 1996 and today
Carbon emissions today are equivalent to 1976 levels despite an increase in campus SF served from 9M SF to 17 M SF.
For more information on UT Austin, visit: About the Carl J. Eckhardt Combined Heating and Power Complex
If you mention Princeton in the context of energy, most people think of Super Storm Sandy in October, 2012 and how the university’s district energy CHP microgrid maintained operations through the storm, keeping the campus and community supplied with electricity and heat even while the surrounding areas were left completely without power. When Sandy hit, Princeton kept the lights and heat on thanks to their CHP-based microgrid, even supporting local area first-responders as an area of refuge.
Another benefit of CHP at Princeton is fuel flexibility. The system is designed to use several inputs including grid electricity, solar pv from an on-campus farm, natural gas, diesel, recovered heat, and bio-diesel fuel. The plant’s operations system includes various meters and controls which allow plant operators to monitor and predict metrics like energy demand from the campus and forward electricity prices to make real-time operational decisions whether to make or buy power from the grid on any particular day. When the price of grid power goes negative, Princeton effectively gets paid to make chilled water for storage into a large thermal tank for later use to air condition the campus and further offset electricity demand during higher-priced periods. Additionally, because they have aggregated the heating and cooling needs of 150 buildings into the central plant, Princeton has the ability to switch from natural gas to bio-diesel as price or supply dictates. It will be much simpler to convert the single central plant to low-carbon fuel than 150 individual boilers in each building. Their CHP microgrid enables the university to pay lower prices for energy, saving them millions on energy costs each year. In addition to monitoring demand and price, “emissions are rigorously monitored” as well and the emissions reductions generated by the CHP plant means that Princeton “is on track to reduce CO2 emissions to 1990 levels (95,000 metric tons) by 2020.” And like UT Austin, Princeton continues to achieve these emissions reductions even while their campus real estate grows. Energy efficiency through CHP is a critical advantage paying continuous dividends.
Harvard has been using district energy to supply resilient energy to its campus for nearly a century and has been an early adopter in the age of sustainability, implementing a greenhouse gas emissions reduction plan in 2008 and entering into a long-term power-purchasing agreement for carbon-free wind energy in 2009. When the university met their emissions reduction goal early in 2016, they credited a reduction of 20,500 metric tons of carbon dioxide equivalent (MTCDE), equal to taking 4,300 cars off the road, to their combined heat and power system, the largest portion of on-site emissions reduction. Even now Harvard continues to demonstrate its global leadership in sustainability by modernizing and optimizing their district energy systems as a means to strengthen campus resiliency and reliability while simultaneously curbing their steam plant’s carbon intensity by 22 percent.
The most recent goals set forth by the University are “to be fossil fuel-free by 2050 and fossil fuel-neutral by 2026.” At the same time, the university is expanding with a new satellite campus in the Allston neighborhood of Boston. Harvard has chosen to construct a new district energy center with CHP in order to meet the new campus’ energy needs and simultaneously work towards meeting those goals. The campus will be fueled by natural gas for now “because that’s the dominant lowest carbon fuel source available for this scale of facilities,” but flexibility provided by the energy center means that “As low and zero carbon technologies are tested and proven, they can be evaluated for incorporation” into the campus energy system, as the university has done on its main campus where their district energy system has allowed them to utilize technologies like solar thermal, solar PV, and heat recovery.
Bob Manning, Director of Engineering & Utilities at Harvard University, recognizes that the New England electricity grid is getting cleaner through greater penetration of more renewables over time, and sees a future where operating decisions are based on real-time carbon intensity. “We see district energy as an enabling platform, providing us with the flexibility to make real-time adjustments based on both the carbon intensity of the grid and the fluctuating price of power. Our system will be able to optimize between on-site CHP generation and purchased power, especially as the grid gets greener. With thermal storage, we can shift production to the hours when carbon intensity is low and when pricing drops or even goes negative. The round trip efficiency will be much better than current battery technology.”
Changes to energy supply and demand on campus accounted for the largest percentage of emissions reduction. Graphic by Judy Blomquist/Harvard Staff
Rendering of Harvard District Energy Facility to support Allston campus expansion. Courtesy Leers Weinzapfel Associates
For more information, please visit: Harvard Harnesses CHP to Meet Emission Reduction Targets
Massachusetts Institute of Technology
Like others in this list, MIT sees its cogeneration plant as a key component of their sustainability strategy, “crucial to supporting MIT’s research and educational activities,” and a “flexible power system that positions the Institute to explore emerging sustainability and efficiency measures.” Sustainability, reliability, resiliency, and energy efficiency are some of the main benefits of CHP and reasons why MIT has chosen to reinvest in its cogeneration system. Compared to a traditional campus energy system the existing plant at MIT has used a third less fuel and helped avoid almost 1.3 million metric tons of GHG emissions in its lifetime. The newly upgraded plant will offset “a projected 10% increase in GHG emissions due to energy demands created by new buildings and program growth” while still being able to maintain high reliability needed to support its research and other world-changing activities. Achievements like that can be attributed to a substantial increase in energy efficiency reached by upgrading their CHP system from its current 22 MW capacity to 44 MW capacity.
MIT has committed to “reducing greenhouse gas emissions at least 32% by 2030.” Perhaps the most important function of the CHP plant and district energy system at MIT is to serve “as an effective bridge to evolving energy technologies.” As critics point out, a natural gas-powered system is not an environmental holy grail, but due to the energy dense and mission-critical nature of many university facilities a cogeneration plant powered by natural gas is one of the cleanest and most efficient proven options available today. Ken Packard, MIT’s Director of Utilities, says that “With this system MIT will be better positioned to explore additional sustainability and efficiency measures, and we’ll be able to incorporate emerging energy technologies as they become available. We are collaborating with the Office of Sustainability on an energy strategy that defines our goals for the future, including at least a 32 percent reduction of campus greenhouse gas emissions by 2030. Cogeneration is the bridge that will get us there.”
University of New Hampshire
At the University of New Hampshire, operating a cogeneration plant has made it economically feasible for the university to transition from fuel oil to natural gas to landfill gas, reducing their carbon emissions every step of the way and becoming “the first university in the country to use landfill gas as its primary fuel source.” Like UT Austin recognizes where natural gas falls short, UNH acknowledges that there are valid arguments against the use of landfill gas as their primary fuel source, however “since we have only a decade in which to substantially reduce our greenhouse gas emissions to avoid the worst impacts of climate change, we need to explore renewable power sources like landfill gas.” And the combination of CHP and landfill gas has been extremely effective at reducing the university’s emissions to meet their goals of “a 50 percent cut in greenhouse gas emissions by 2020 and an 80 percent cut by 2050,” the cogeneration plant alone “resulted in an estimated reduction in greenhouse gas emissions of 21%.”
For more information, please visit: Meeting Campus Emissions Requirements with Landfill Gas; UNH Cogeneration Facility; UNH Energy & Utilities; A Successful CHP Project at the University of New Hampshire
University of Missouri
The University of Missouri Columbia operates arguably one of the most efficient and greenest university campuses in the nation, achieved through continuous focus on energy management and conservation, CHP and integration of renewables. Since 1990, Mizzou has reduced its energy use per square foot by 20 percent, realizing over $71.2 million in savings. By investing in efficiency and cutting demand, the combined cost avoidance and energy savings now amounts to $9.4 million annually. Moreover, the university’s renewable portfolio of biomass, wind and solar produces 40% of total annual energy needs, “now generating more renewable energy on [their] campus than any other university in the country, achieving a 50% reduction in GHGs from its base year of 2008,.” Additionally, the 66 MW campus energy microgrid can produce 100% of the power requirements for the campus, enhancing the resiliency and reliability for a modern research-driven public university campus, an important economic engine for the community.
For more information, please visit: University of Missouri CampusEnergy2017 Student Video Contest; University of Missouri Renewable Energy; University of Missouri Energy Efficiency
The lessons learned at these campus district energy systems can provide valuable experience and insight to others in the regional economy, especially nearby communities, cities, industry and military bases seeking enhanced resiliency. As active members of the International District Energy Association (IDEA), these universities share a 109 year tradition of open peer exchange to help advance technology, innovation and best practices, supporting collaboration that produces remarkable economic and environmental gains for their institutions. To learn more, please visit www.districtenergy.org and let us know if you would like to arrange a site visit to see smart energy in action. Make plans to attend Microgrid 2.0 in Baltimore Oct 29-31, 2018 to meet with and hear many of these university leaders.