Information: The five units received a building energy report along with information about the $40 per metric ton of carbon dioxide equivalent (mtCO2e) price without financial consequences.
Target: The units had a reduction goal of 1 percent below their baseline. They were charged or received a rebate of $40 per mtCO2e for emissions above or below their baseline, respectively.
Redistribution: The units were subject to a revenue-neutral scheme in which each unit was compared to the group’s overall percent change in emissions from the group’s baseline. These units incurred a charge or a rebate based on emissions relative to the baseline value.Investment: They received a subsidy equal to 20 percent of their baseline carbon charge for investment on energy efficiency. This scheme was an attempt at simulating the second year of the program during which those units that performed well would spend a portion of their carbon charge revenue on building efficiency, education and outreach, and energy conservation initiatives.
What was the relative impact of various factors on the change in emissions for buildings during the pilot?
We found that it may be more difficult for larger buildings to reduce their emissions and, conversely, it may be easier for energy intensive buildings to reduce their emissions. Our results indicate that bigger buildings had a harder time reducing their emissions than smaller buildings, and units that are more energy intensive were able to reduce their emissions by more than units that had a smaller baseline energy use.
Did instituting a carbon charge, no matter the design, influence the emissions of participating Yale buildings?
All treatment groups that participated in the Carbon Charge experienced a statistically significant reduction in emissions relative to their baseline. These results are positive for the Carbon Charge Program at Yale, justifying their efforts at instituting a price on carbon in order to decrease campus emissions.
However, emissions for all Yale buildings, not just those that participated in the pilot, decreased relative to their baseline. This could be due to the fact that the winter during the 2015-2016 academic year was warmer on average than the previous five winters, and all units used less energy for heating.
Which was the most successful carbon pricing scheme at achieving emission reductions?
Our results conclude that investment in spending on self-guided energy actions led to the greatest emission reductions. Given that the Investment scheme was found to be associated with the greatest reduction in emissions relative to the other treatment groups and the control, we sought out the administrators for the five business units in that treatment to investigate what actions that took to reduce their emissions. We found particularly interesting results from La Casa Cultural and Stoeckel Hall.
La Casa Cultural (301 Crown Street) used funds from the Carbon Charge Investment scheme for signage around the building to communicate energy efficiency practices, such as turning out the lights, closing windows, and utilizing recycling bins.
Stoeckel Hall converted manual light switches to motion activated ones in restrooms and public areas, as well as reducing heating requirements by adjusting set points as to not heat areas unnecessarily late in the evening.
For F&ES, Kroon Hall was included in the redistribution scheme during the pilot program. During the pilot, F&ES worked on technical solutions to reducing the building’s energy use (such as adjusting the occupied hours of the building and installing a thermal curtain in one office space). In addition, a communication strategic plan was created that included using social media, email, articles, and video interviews to discuss the Carbon Charge and improve its educational value to the community. Due to these efforts, Kroon Hall reduced emissions by 17 percent relative to our baseline for a total rebate of $630.90. This rebate went towards the F&ES Environmental Stewardship Committee to further energy reduction efforts on campus.