The greatest potential for reducing emissions lies in energy efficiency and in switching to renewable fuel sources. Although UNC has an efficient, award-winning cogeneration facility, coal is a carbon-intensive fuel. Co-firing coal with a solid biomass fuel is a potentially viable short-term strategy. Torrefied wood, a dense charcoal-like substance, has a high energy value and can be made from waste wood. The torrefaction process can also produce fuels from agricultural wastes. Pellets of torrefied fuels with surface areas to facilitate combustion have been test-fired with coal to assess the feasibility of burning this fuel in existing campus boilers. In Fall 2010 and April 2011, UNC completed the first pilot burns of torrefied and pelletized wood. The project is on hold while the University continues to search for a company willing to supply torrefied wood. In 2013, UNC avoided using over one trillion BTUs of energy, which is equivalent to the electricity generated by burning 40,500 tons of coal at a traditional generating facility.
A new 1,000 kilowatt generator at Carolina North converts gas from the Orange County landfill to 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. During the first five months of operation, the generator used 42 million cubic feet of landfill gas, which contains about 50% methane. The same amount of landfill gas was flared. Now that the generator is operating full-time, less gas will be flared. Together, these activities kept 30,000 tons of carbon dioxide from entering the atmosphere, or the equivalent to the annual greenhouse gas emissions of 8000 passenger vehicles.
Methane is produced when waste decomposes in a landfill. Its global warming potential is at least 21 times higher than carbon dioxide. By keeping methane out of the atmosphere, the University receives carbon credits and moves toward its goal of becoming carbon-neutral by 2050.
Solar energy technologies provide significant opportunities for space and water heating and for generating electricity. Three-dimensional aerial maps indicate which campus roofs have the appropriate slope and orientation to accommodate solar energy technologies. Photovoltaic panels covering the south-facing roof of the North Carolina Botanical Garden Education Center generate nearly 8% of the building's electricity from sunlight and is the first to sell solar-generated electricity back to the campus grid. Morrison dormitory on South Campus has implemented its own solar heating installation with help from RESPC. One-hundred seventy-two solar thermal panels mounted on the roof of all four building wings provide heat to the domestic hot water and building heating system, two sets of which face southeast and two which face southwest. The residence hall's plumbing system draws first on solar-heated water from a 6,000 gallon storage tank and adds steam-heated water when needed.
Carolina's Energy Frontier Research Center for Solar Fuels advances emerging solar energy technologies and devices that can efficiently produce fuels. The research focuses on innovative interdisciplinary research, including improved generation of fuels and electricity from sunlight. The center involves more than 20 faculty, 30 postdoctoral fellows and graduate students, and collaborations with scientists from multiple universities.
Although North Carolina’s central Piedmont is not rich in wind resources, the mountains and coast experience strong, steady winds that may be suitable for generating electricity. At the request of the North Carolina General Assembly, Carolina conducted a feasibility study of coastal wind potential in 2009. The assessment addressed ecological risks and synergies, available transmission capacity, carbon reduction potential, economics, and utility statutory and regulatory constraints. Preliminary findings indicate that there is potential for economically attractive, utility-scale production of wind energy off the coast of North Carolina and within the eastern Pamlico Sound. The study team recommended aggressive pursuit of offshore wind energy and careful study of new federal regulatory processes. A 2010 study by Duke Energy Carolinas gathered extensive data on the presence of birds, fish, and marine mammals in the areas well-suited for wind development during all seasons of the year.
Other opportunities for emission-reduction addressed in the Climate Action Plan include new “green” development, improved efficiencies within the energy supply infrastructure, demand-side efficiencies in existing buildings, behavioral changes to reduce energy demand, enhanced waste management and purchasing practices, and more multi-modal transportation options.
UNC Energy Services - http://www.energy.unc.edu
UNC's Climate Action Plan website - http://climate.unc.edu
North Carolina Botanical Garden - http://www.ncbg.unc.edu