Based on Arlington’s proven commitment to reduce our energy consumption and our environmental impact, it should come as no surprise that there is keen interest in building a new high school that is sustainable. The new high school should not only meet our educational needs for the 21st century, but also help us fulfill our commitment to environmental stewardship while minimizing the operating costs of the Town’s largest building and biggest energy user.

The question isn’t whether sustainability factors into the design of the new high school but rather, how we build the most sustainable building possible. More specifically, how do we build a facility that minimizes lifecycle costs and environmental impacts, contributes to the creation of a welcoming and healthy space for learning, and where the building itself becomes a core element of the educational experience?

Sustainability subcommittee

Last month an AHS Building Committee Sustainability subcommittee was established. This group brings a broad range of relevant technical expertise as well as a passion for sustainability and a strong desire to make the new AHS a net-zero energy building (meaning it produces as much energy as it uses over the course of a year). The committee is comprised of:

Ryan Katofsky and Kate Loosian from the AHS Building Committee
Representatives from our architect (HMFH) and our Owner’s Project Manager (Skanska)
Several of the subcontractors to HMFH that have expertise in engineering, heating and cooling systems, and net-zero energy buildings
Kevin Settlemeyer, an Arlington resident with sustainable building design experience
The Town’s Energy Manager, Ken Pruitt
The Arlington Public Schools’ Sustainability Coordinator, Rachel Oliveri
Three student representatives from the AHS Sustainability Club and their faculty advisor, Kent Werst.

Given the relatively early stage of the project, the Sustainability subcommittee’s first decision was to select a green building rating system to use for the design (LEED was chosen). This will serve two purposes:

Achieving a sufficiently high LEED score and level of energy efficiency will increase reimbursement from the MSBA by 2%. For a project of this scale, this could increase reimbursement from the state by several million dollars.
The rating system can help guide efforts to design a building that addresses sustainability from multiple dimensions, including energy and water use, on-site energy production, materials selection, stormwater management, and building commissioning.

Sustainability Goals

The subcommittee developed a list of recommended sustainability goals for the project. These cover issues related to:

Energy production and use
Managing the flows of waste within the building (e.g., recycling and organics separation, such as food scraps)
Using the building as a teaching tool
Quality of the indoor environment
Transportation

A forward thinking design is essential. For example, designing a building that can run free of fossil fuels within the lifetime of the new building should be explored. This would suggest a heating system that runs on electricity as opposed to natural gas, or one that can be easily converted in the future. Similarly, there is desire for the new building to make it easy to recycle and to separate and collect food scraps, so they can be composted or turned into renewable energy, rather than sent to a dumpster. Lastly, on-site parking could be “electric vehicle ready” so that charging stations can be added easily in the future.

Preliminary Evaluation Matrix

The subcommittee conducted a preliminary assessment of the four preliminary conceptual designs. Though it’s too early in the process for detailed designs or building energy modeling, the subcommittee used the expertise of the members to identify any major differences between the four design concepts. For example, the available roof area for solar panels, the ability to drill wells for a geothermal heating and cooling system (a very efficient way to heat and cool buildings), and the total amount of exterior wall area (an indicator of which building will have a greater ability to retain heat in winter and stay cool in summer) are all strong sustainability indicators.

The results of this preliminary assessment are shown in the table below.

This matrix suggests that there are not large differences between Alternatives 1, 2, and 3, but Alternative 4 has some drawbacks. Among Alternatives 1, 2, and 3, Alternative 3 has, in the current view of the subcommittee, the greatest opportunity to achieve a passive energy design, owing to the all-new construction and the fact that it has the smallest exterior wall area (30% less than Alternative 1). Coupled with good roof space for solar panels and modest potential for geothermal wells, Alternative 3 appears to offer the best combination of features from a sustainability standpoint.

Building on Arlington’s Sustainability Record

Arlington’s sustainability efforts not only save the Town money by reducing energy consumption, but they also reduce our environmental impact and often improve the quality of the services being delivered. Following are highlights of just some of the existing programs throughout the community:

In 2015 and 2016, rooftop solar power systems were installed on six schools.
The Town was an early adopter of LED traffic signals and streetlights, reducing electricity use for these applications by about 75%.
There have been many energy efficiency improvements made to town buildings over the years, including interior and exterior lighting, heating & cooling equipment, refrigeration, and energy management systems.
A community choice aggregation program has increased the renewable energy content of the electricity used by most residents and businesses while reducing the price and providing greater price stability compared to Basic Service from Eversource.
This year, the Arlington Public Schools was one of six districts from across the country to receive the U.S. Department of Education Green Ribbon School District Sustainability Award, recognizing our achievements in reducing greenhouse gas emissions, efforts to address the nutrition, fitness, mindfulness, and overall health of students and staff, and the incorporation of curricula that address environmental topics at all school levels.
Arlington also recently joined the Metro Mayors Coalition, which includes a commitment to making Arlington carbon neutral by 2050.

In addition, hundreds of homes and a number of businesses have installed rooftop solar power systems. These efforts prepare us to manage the impacts of climate change, reduce pollution, improve the quality of life in Town, enhance our students’ well-being, and position them for careers in sustainability and clean energy.

Of course, sustainability is just one of many factors that was considered by the building committee when selecting the preferred design concept. As the design process moves forward, the Sustainability subcommittee will work hard to create the most sustainable design possible.