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Wednesday, Apr 24, 2024

Carbon Countdown: Heating Up the College

The largest contribution to the College’s carbon emissions comes from heating and cooling buildings. When the Climate Action Plan (CAP) was implemented in 2008, heating and cooling constituted 89 percent of the College’s emissions. Most of the emissions came from the combustion of  no. 6 fuel oil to heat and cool buildings; the College was burning about two million gallons per year, which released 23,877 metric tons of carbon dioxide equivalent (MTCDE) in 2006-07. Another 2,009 MTCDEs came from the combustion of no. 2 fuel oil, and 623 from propane. The CAP clearly stressed the need to use carbon neutral fuel sources to heat and cool the campus if the College is to reach carbon neutrality by 2016.

The College’s biomass plant, opened in 2009, was a major step toward making the College carbon neutral.

There are two important questions when considering the biomass plant. How does it function, and how does this correlate to reduced net emissions? The College’s plant uses a process known as biomass gasification, where woodchips are superheated with a controlled amount of oxygen so that they do not actually combust. The resulting gas, called syngas (synthetic gas), is then combusted and the heat is used to make steam, which is piped throughout campus to heat, cool, make hot water and cook. This method of combustion is very efficient, and is carbon neutral because the same amount of carbon dioxide is released as is absorbed by the trees that are consumed in the process.

While the net emissions from the biomass plant are zero, this does not mean it has no emissions. The emissions from the plant are not significantly lower than those from burning fuel oil, but the biomass facility utilizes a filtration system to clean up the exhaust, removing 99.7 percent of particulates.

The emissions resulting from chipping and transporting the wood to the biomass facility are not factored into the assessment of carbon neutrality.

Another important aspect of biomass is where the fuel comes from. The College joined with the State University of New York College of Environmental Science and Forestry (SUNY-ESF) on a project to test the feasibility of willow shrubs as a source of wood chips for the biomass plant. Willow shrubs are fast growing, and could be planted on unused farmland to generate additional income for local farmers. After the first harvest in 2010, it was determined that willow shrubs are not an effective fuel source for the College’s biomass plant. The College continues to source their chips from logging operations within a 75-mile radius.

In addition to the use of biomass to generate steam, heating and cooling emissions can be reduced by improving building efficiency. When the CAP was assembled, a survey of buildings at the College indicated that 53 percent of the square footage on campus performed well below current energy code standards.

Since the report, the College has indeed made strides to improve the performance of its infrastructure. In 2008, Franklin Environmental Center at Hillcrest received Leadership in Energy and Environmental Design (LEED) Platinum certification, the highest possible certification. More recently, the squash center also obtained LEED Platinum certification, and the College is seeking LEED Gold certification for the new field house.

Unfortunately, the new townhouses being constructed in Ridgeline will not be required to be LEED certified. The College’s agreement with Kirchhoff Campus Properties, who is building the new dorms, does not require the company to seek LEED certification for the complex. Given the recent progress with the squash center and Virtue Field House, this is a disappointing step in the wrong direction for the College.

All of the College’s developments have contributed to a 66 percent reduction in net emissions from stationary combustion sources, such as boilers, heaters and ovens. From 2013 to 2014, the College emitted only 8,996 MTCDEs due to stationary combustion, as compared to 26,509 MTCDEs in 2006-2007.

Recent improvements have contributed to reduced net emissions and reliance upon fossil fuels, but have not solved the College’s heating and cooling problem. The biomass plant eliminated the need for one million gallons of no. 2 fuel oil each year, leaving another million gallons to address.  What has the College done about the next million gallons of fuel oil and what can still be done? That is the “million gallon question.”


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