Energy Supply

Increased efficiency and use of renewable energy sources are the keys to powering the University in a sustainable way.

Energy Generation

cogeneration plantCarolina’s main source of power comes from a highly efficient 32-Megawatt cogeneration plant. This combined heating and power system is used primarily to produce steam which is piped to 175 campus buildings including UNC Hospitals, for heating, humidification, hot water heating, sterilization, and making distilled water in laboratories. This steam is also used to generate electricity, with the capacity to meet one-third of the University’s peak demand. This dual function results in an overall efficiency that is twice that of any plant built solely for the purpose of power generation. The cogeneration plant has won multiple awards for cleanliness and efficiency from the U.S. Environmental Protection Agency. In 2008, the EPA recognized UNC for reducing greenhouse gas emissions equivalent to taking 9,011 passenger vehicles off the road.  In 2009, the University developed a Climate Action Plan (CAP), which sets attainable and measurable goals to reach climate neutrality by 2050.

Currently the plant is fueled primarily by coal. UNC purchases coal from mines that do not practice mountain-top removal, a mining practice that can irreparably harm local ecosystems. Within the plant, generating steam in circulating fluidized bed boilers reduces emissions of sulfur dioxide and nitrogen oxide. Adding calcium-containing products such as limestone to the combustion chamber reduces sulfur dioxide. By keeping the combustion temperature much lower than conventional fossil fuel combustion temperatures, nitrogen oxide production is minimized to 1,600° F as opposed to more than 2,200° F.

In 2010, Chancellor Holden Thorp commissioned an Energy Task Force to study energy issues on campus. The chancellor accepted all of the group’s recommendations, which included:

  • Accelerate conversion from coal to a cleaner fuel or fuel mix;
  • Source biomass, if used, from certified “sustainably managed” forests, as determined by third-party verification;
  • Make best efforts to identify and secure coal that is certified by a third party and sourced from deep mines only;
  • Optimize use of natural gas as supplies and costs warrant; and undertake periodic reviews of the potential for solar thermal and solar photovoltaic system installations.

The first pilot burns to test biomass fuels at the cogeneration plant took place in fall 2010 and spring 2011. A 20% mix of pelletized & torrefied wood was used in the successful pilot burn.

Cooling the campus is the job of five networked chiller plants. These plants use a combination of electric centrifugal and steam absorption chillers to cool water, which is then pumped to 166 buildings. Two satellite campuses are also served by district chilled water systems. A 5-million gallon thermal energy storage system shifts a portion of the University’s chilled water production to off-peak periods. Electric cost savings range from $108,000 to $459,000 annually, depending on the peak and off-peak electric rates charged by Duke Energy.

In fall 2011, Student Government requested that UNC allocate some of its money into a Green Revolving Fund, which provides low-interest loans to energy conservation, efficiency, and production projects around campus. Chancellor Thorp congratulated the students’ innovative thinking and allocated $500,000 to the fund in fall 2011.

In 2013, a new 1,000-kilowatt generator at Carolina North began operations. The generator converts gas from the Orange County landfill into electricity for the grid. The University and Orange County negotiated the Landfill Gas Recovery Agreement in 2009 as a way to reduce carbon emissions, provide a revenue stream to Orange County, and advance UNC’s carbon-neutrality goals. The University sells the electricity to Duke Energy and plans to ultimately use the waste heat for buildings at Carolina North.

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UNC Energy Services

Renewable Energy Special Projects Committee

Driven by student initiatives, the University has also begun to incorporate renewable energy technologies on campus. During the student elections of 2013, 83% of students voted to make permanent a $4 per semester student fee that funds energy, efficiency, and renewable energy projects. First imposed in 2004, the fee raises approximately $200,000 annually. As the first recipient of an RESPC loan, Lenoir Dining Hall used the loan to purchase Energy Star appliances and LED lighting for the renovated second floor. RESPC has budgeted a total of $1,642,280 for loans, with about 50% of the money directed towards renewable energy and about a quarter towards renewable energy and about a towards indoor and outdoor LED and other lighting and equipment upgrades. RESPC also budgets money towards heating and cooling system makeovers and energy education.

The student-run Renewable Energy Special Projects Committee, an arm of Student Government, allocates the fee. Some investments to date include:

  • A 174-panel solar hot water system on top of Morrison Residence Hall to provide heat to both the domestic hot water and building heating system
  • 31 geothermal wells at the N.C. Botanical Garden Education Center to provide heating and cooling in the building
  • 135 LED lights in the open, central staircase at the Medical Biomolecular Research Building to replace 20 watt halogen lights
  • A solar hot water system that will be installed on top of Fetzer Gym when the roof is replaced
  • Funding for a two-year pilot program of Tar Heel Bikes, a student developed project that allows on South Campus to rent bikes for free
  • Funding to install 19.8 kw solar array on top of the FPG Student Union.

In 2011, the RESPC implemented a program to increase the effectiveness of its funds on campus, which has led to funding for receipt-supported entities, like housing and dining.  90% of the money will be repaid through avoided energy concepts.

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Renewable Energy Special Projects Committee

Energy Demand

With rising energy costs and the construction of new buildings, the University’s annual energy bill now tops $89 million. Energy use at UNC has declined 29 percent per square foot since 2003 despite a square foot expansion of 41% in the same period, saving the University $261 million in avoided energy costs. This has created a clear need for active energy management and conservation. In 2008, a new Energy Management Department was formed within the Facilities Services Division to consolidate energy saving functions. A new campus energy policy and aggressive conservation measures adopted in 2009 are projected to increase energy savings significantly.

Lighting

Lighting consumes 25 to 30 percent of the electricity in classroom and office buildings and is a high priority for efficiency upgrades. Over the past 15 years, all of the overhead lighting on campus has been converted from inefficient T-12 light tubes with magnetic ballasts to smaller diameter T-8 or T-5 light tubes with electronic ballasts. The result is better light, a 20% savings in electrical consumption, and substantially reduced maintenance calls. Ninety percent of building mechanical rooms have been equipped with timers to turn off the lights. Forty percent of common spaces, such as restrooms, break rooms, and conference rooms, contain occupancy sensors.

Standard, screw-in incandescent lights bulbs have been eliminated in all campus buildings and desk lamps. They were replaced with more than 4,000 compact fluorescent light bulbs that use only one-quarter of the electricity and last many times longer.

Recent improvements in the cost and efficacy of LEDs (light emitting diodes) have encouraged the University to begin testing a variety of fixture types on campus, both indoor and outdoor.  Electric costs at the LED-lit Bell Tower Parking Deck are so much lower than at other decks that Parking Services plans to convert all decks to LED lighting. At the Ackland Art Museum, more than 400 recently installed LED bulbs will reduce energy used for lighting by 87% and improve lighting quality. Costs will decline by $13,000 annually and carbon dioxide emissions will fall by 73 tons.

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Operating Efficiencies

Building energy consumption accounts for 79% of campus greenhouse gas emissions, so managing existing buildings is key to reducing Carolina’s carbon footprint. Many current and future energy efficiency improvements are focused on building automation system controls, operating protocols, and individual behaviors. In 2009, UNC Energy Management launched an aggressive campaign against energy waste in all areas of campus. The Energy Conservation Measures Program is a building commissioning effort utilizing in-house labor, outside contractor support, and minimal funding to achieve low-cost energy savings. Analyzing and upgrading over 10 million square feet of building space since 2009 has resulted in almost 30% energy savings, or $22 million in energy savings. The program focuses on heating and cooling systems in existing buildings.

Regular recalibration of equipment and systems, broader temperature ranges that correspond with the seasons, setting back air handling systems when buildings are unoccupied, and reprogramming building automation systems can result in major savings.

In 2010, UNC entered the EPA‘s first annual Working Off the Waste Competition. UNC’s Morrison Dormitory won the national competition, reducing energy use by 36% and preventing 733 metric tons of greenhouse gas emission during the course of the competition on a budget of less than $35,000. Morrison continues to participate in this competition each year, remaining a leader in sustainability.

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UNC Energy Management

Energy Management Control System

Real time electric metering has recently joined steam and chilled water metering in virtually every building on campus. The online Dashboard, developed by UNC’s Energy Services department, includes data on more than 200 buildings. The online Energy Dashboard, developed by UNC’s Energy Services department, includes data on more than 200 buildings. The graphic display provides hourly, daily, weekly, monthly, and near real-time data for steam, electricity, chilled water, and solar use, and will eventually provide monthly data for water use. By making the data visible to the Carolina community, building occupants and maintenance personnel can see the impact of actions and behaviors on energy consumption.

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Behavioral Change

Promoting responsible energy consumption is a cornerstone of UNC’s energy conservation program. To learn more about these efforts, please visit the Behavior Change page.