Reducing Greenhouse Gas Emissions Through Targeted Renovations
Two historic colleges worked to improve energy efficiency.
Every day more colleges and universities across the country are making greenhouse gas reduction and carbon neutrality goals. To reach these goals, they must tackle the problem of Scope 1 emissions (emissions from facilities and fleets). Existing buildings often create most of these emissions through their dependence on fossil fuels to produce energy for space heating, domestic hot water production, and building uses such as research laboratories. The task of identifying, prioritizing, and finding solutions for the challenges associated with energy production and numerous buildings of different eras, programmatic uses and MEP systems can be a daunting one.
To implement climate action plans with the goal of campus carbon neutrality, the energy inputs needed for space conditioning will require significant reduction, and this is often the starting point for institutions. Once energy use by individual facilities is reduced, energy generation – be it from central plants or dispersed generation sources – must be transitioned to sustainable, renewable sources. The implementation of these projects is complex, requiring deep engineering expertise, but also the involvement of architects to achieve coherent, cost-effective, and integrated building and campus-level solutions to decarbonization.
Two Colleges’ Approach to Decarbonization:
Wellesley College, Wellesley, Massachusetts
In 2019, Wellesley College commissioned a study of Severance Hall, one of its 20th century residence halls, as a model of how it might complete significant deferred maintenance, infrastructure, and accessibility upgrades across their campus. Simultaneously, Wellesley was in the midst of an energy master plan. The purpose of the master plan was to determine how the college might meet their “E2040” goals of reducing greenhouse gas emissions by 90 percent compared to 2010 levels. A major contributor to GHG emissions on Wellesley’s campus, as at many other universities, are Scope 1 emissions from their buildings. The energy master plan looked at ways to reduce GHG emissions from space heating and cooling across the entire portfolio of buildings. The historic residence halls, including Severance, connect to the campus steam loop and are heated either with steam or hot water radiators. The major work of the master plan involves the conversion of the campus from a steam distribution loop to low temperature hot water. This changeover to low temperature water will support potential geothermal installations, gradually reducing energy input and therefore carbon emissions. The college worked with several third-party experts to determine the best approach to building space heating systems in anticipation of this change.
Phase I of the Severance Hall project is nearly complete. In careful consultation with the college, engineers, and specialty consultants, new insulated partitions on the interior side of the building’s exterior walls have been installed. Existing steel windows have been repaired and sealed, and interior storm windows sit within historic stone surrounds. Mechanical ventilation has been added to the attics, and new radiators – sized for low temperature hot water - have been installed. These interventions improve envelope performance through increased R-values and air sealing while meeting tight budgetary constraints and will serve as the model moving forward for the retrofitting of the college’s residence hall portfolio.
Amherst College, Amherst, Massachusetts
Amherst College is a private college founded in 1821 in Amherst, Massachusetts. Their recently published climate action commitment states the college’s goal “to achieve climate neutrality by 2030 through transformative modernization of our energy system from fossil fuels to renewable electricity. By focusing on eliminating fossil fuel combustion, we will not have to rely on carbon offsets to meet our goal. In addition, we aim to go beyond just carbon neutrality on our own campus, inspiring graduates who will lead change on a much larger scale.”
The initial scope involved the envelope and architectural review of eight existing buildings. (ca. mid- 1800s to 2004), including gymnasium, library, and academic, and residential buildings. Working with third-party experts, building envelopes were assessed for areas of energy loss and potential synergies of envelope upgrades that would complement the campus low temperature heating hot water conversion. A set of envelope Energy Conservation Measures (ECMs) were developed and evaluated for their energy savings and cost implications. A final report also noted potential construction ease or difficulty, as well as code or accessibility issues such upgrades might trigger.
Based on the final recommendations in a feasibility report, the team moved into Phase I implementation. This has included significant engineering and early phase architectural work for the replacement of steam and high temperature hot water systems at 26 campus buildings, as well as schematic design for a new campus Energy Center. Work at the existing buildings ranged from detailing plaster or millwork where radiators in historic spaces require replacement as well as determining optimal pipe routing in other buildings to minimize unnecessary architectural work. The purpose of the Energy Center is to house the mechanical equipment to support distribution of low temperature hot water and chilled water produced by the new campus geothermal system. In addition to concerns regarding operational carbon, in conversations with Amherst College, the Energy Center was planned as a low-embodied carbon structure, utilizing heavy timber construction with a green roof and only minimal finishes. While the Energy Center will be part of later phases of the project, the schematic design enabled pricing for incorporation into future phase budgets. Building assessments, design of a new campus Energy Center, and the ongoing work on the integration of new heating and cooling systems into existing buildings on campus, will help Amherst College achieve their ambitious goal of climate neutrality by 2030.
Rebecca Berry is director of sustainability for Finegold Alexander Architects. She leads Finegold Alexander’s higher education, institutional and religious practice areas.