Carbon Countdown: Electricity Use Maintaining Large Carbon Footprint

Beyond emissions from heating and cooling, travel and waste, the College must address emissions from purchased electricity in order to reach its goal of carbon neutrality by 2016. When the Climate Action Plan (CAP) was adopted in 2008, electricity purchases accounted for only 2 percent of the College’s total carbon emissions. By 2014, this figure had risen to almost 7 percent. Though this was largely due to a decrease in total gross emissions from heating and cooling, emissions from purchased electricity did rise from 676 metric tons of carbon dioxide equivalent in 2007 to 864 tons in 2014.

The College uses about 22 million kilowatt hours of electricity per year. Of this energy, 20 percent is cogenerated on campus by turbines connected to the central heating plant. The steam generated by the plant (from biomass and fossil fuel combustion) drives turbines, which generate electricity. The steam is then piped throughout campus to meet the heating and cooling demand. The remaining 80 percent of the College’s electricity is purchased from the Central Vermont Public Service Corporation (CVPS). Because the combustion of biomass is considered carbon neutral, it is this purchased electricity that accounts for the College’s net carbon emissions from electricity usage.

When the College purchases electricity from CVPS, it cannot control the source of the electricity or whether it is carbon neutral. Until 2013, the vast majority of Vermont’s power (70 percent) came from nuclear energy, which is carbon neutral. Much of the remainder of the state’s electricity came from hydropower, another source of clean energy. Most of Vermont’s nuclear power came from the Vermont Yankee nuclear power plant, which shut down in late 2014. Due to this, utilities have since had to purchase electricity from non-renewable sources.

Green Mountain Power, which recently merged with CVPS, predicts that only 55 percent of its fuel mix in 2015 will be renewable, coming from nuclear and hydroelectric sources. The other 45 percent of its fuel mix will consist mainly of “system” power, which comes from various sources, including fossil fuels. In calculating carbon emissions from purchased electricity, the College must factor this in.

To help reduce net emissions from electricity, the CAP recommended conservation as well as investigating alternative energy sources, such as wind and solar power.

In 2012, well after the CAP went into action, the College installed a small 143kW demonstration solar system near McCardell Bicentennial Hall, which consists of 34 solar trackers. In total, the system produces about 200,000 kilowatt-hours annually, which is only one percent of the College’s total electricity consumption. According to the College’s website, the electricity generated by this system is enough to power Forest Hall throughout the year.

Though solar power could be used to offset the College’s energy usage, it is not currently feasible for large-scale power generation. Because of the relative inefficiency of modern solar panels, the College would need a huge solar system to meet its energy needs. This presents multiple problems, including the physical infrastructure of the system and energy storage.

In order to further reduce net emissions from electricity purchases, the College should continue to focus on reducing electricity consumption. Signs asking students to turn off lights when they leave the room have become increasingly prevalent on campus and help to encourage more sustainable practices. Despite these efforts, there is the sentiment that students are still largely unaware of the impacts of their lifestyle choices on sustainability.

Since 2007, carbon emissions due to purchased electricity at the College have risen by 188 metric tons of carbon dioxide, nearly 30 percent. Though only a small contribution to the College’s overall carbon emissions, reduction of electricity usage or a shift toward renewable energy sources will help the College reach its goal of carbon neutrality by 2016.