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School boards still reeling from the pandemic might lament having to think about another difficult issue seemingly unrelated to our primary mission of education. However, the steadily increasing impacts of climate change and the implications for our students merit our close attention. How should boards approach this thorny issue?

The first step is acknowledging the problem. Scientific consensus is clear that fossil fuel burning has put excess carbon dioxide (among other greenhouse gases) into our atmosphere. These gases warm our planet. As a result, today’s average temperature is 1.1º C higher than pre-Industrial Revolution temperatures. Temperature increases are expected to deeply imperil the world’s people, increasing a host of hazards such as heat waves, droughts, and floods. Climate change threatens our communities, ecosystems, and future quality of life for our students.

In response, world governments promised major greenhouse gas reductions. By signing the 2015 Paris Agreement, nations including the U.S. pledged to cut emissions enough to keep planetary warming to less than 2º C, or 1.5º C, if possible.

Unfortunately, the U.S. Congress has so far failed to produce legislation to bring about these commitments. This leaves us school board members, charged with protecting the long-term interests of youth, in the uncomfortable position of watching a towering problem for our students go unaddressed.

Conveniently for us, while climate change is transnational in origin, the solutions are local. This means school districts can, and should, implement them now.

Institutional responses to climate change fall broadly into two areas: mitigation and adaptation. Mitigation refers to measures that reduce human contributions to climate change. For us, this means eliminating school-related production of greenhouse gases. Adaptation measures accommodate the unavoidable realities of a warmer world. These could include ensuring that school buildings can handle increasingly extreme weather and are safe from inundation by rising seas. In this article, I will focus on mitigation.

Several important greenhouse gases exist, but the main one for school districts to think about is carbon dioxide. Small concentrations have accumulated naturally in air, produced by life itself. However, the burning of fossil fuels since the Industrial Revolution has increased concentrations to unsafe levels.

Think about zeroing out your district’s carbon emissions in three categories. Emissions caused directly by equipment we operate are within Scope 1. Scope 2 emissions are caused elsewhere by our purchases of energy. Scope 3 emissions are embedded in the other things we buy.

Scope 1

Scope 1 emissions might be the easiest to understand. We create these by driving fossil-fuel-powered vehicles. Also, our fossil-fuel-powered building heating and cooking appliances create Scope 1 emissions.

The technology needed to eliminate Scope 1 emissions is available today, through a strategy called Electrify Everything. Vehicles and building heating systems can all be powered with electricity, eliminating local emissions. As a bonus, carbon reduction also drives important co-pollutants such as soot and nitrogen oxides toward zero, conferring benefits for community health as we decarbonize. We also will cut costs, as electrification saves energy.

Switching to electric vehicles (EVs) represents low-hanging fruit for districts cutting Scope 1 emissions. Even considering the sources of electricity powering American grids, the Union of Concerned Scientists concluded in 2018 that electric buses “have lower global warming emissions than diesel and natural gas buses everywhere in the country.”

Fundamentally, this is because electric drivetrains convert energy into motion more efficiently than internal combustion engines. They’re also nearly silent and drive smoothly. By cutting transportation fuel use, districts save money. In addition, EVs are built with fewer moving parts and incorporate technologies such as sealed motors and regenerative braking that reduce maintenance costs.

All major manufacturers now offer EV school buses. Trucks and vans are not far behind. E-buses are available in multiple sizes and battery capacities. Unfortunately, ranges are currently less than diesel buses and are further reduced by high speeds, cold temperatures, and the need to heat bus cabins. Driver technique has an important effect on range, penalizing speeding. Districts with long routes might have to schedule midday charging. Under-bus storage may be limited.

Despite these challenges, some school boards are already all-in on bus electrification. Maryland’s Montgomery County School District committed to 100 percent electrification, contracting for 326 e-buses recently. Boston Public Schools is electrifying 100 percent of its fleet by 2030. New York state is planning 100 percent electric school busing by 2035.

Districts making the switch must install charging infrastructure. Battery life is an area of uncertainty for this young industry. Evolving battery chemistries and differences between manufacturers make generalizations difficult. Battery thermal management systems using liquid coolant have improved battery life and performance. Some manufacturers offer battery life of up to 15 years. At the end of life, batteries can be recycled.

Prices for e-buses are currently significantly higher than for their diesel counterparts. Many districts, including my own, were able to bridge the gap with settlement money from the federal Volkswagen Clean Air Act Civil Settlement. My state offers grants under a clean air program that replaces diesel buses with electric ones. The U.S. Environmental Protection Agency is currently funding school bus electrification under provisions of 2021’s Infrastructure Investment and Jobs Act. This program will distribute $5 billion over the next five years, replacing diesel buses with cleaner ones, including e-buses. The first application window is open now and closes on Aug. 19.

In buildings, major Scope 1 emission reductions can come from replacing fossil-fuel heating systems with heat pump technology. Heat pumps are essentially reversible air conditioners that can move heat from inside a building to the outside or vice versa. Overall efficiency is very high because moving heat from one place to another is thermodynamically easier than creating heat through electrical resistance.

The technology draws heat directly from a source, concentrates it to room temperature, then circulates it into classrooms. Evaporators draw heat directly from the air. Higher capacity geothermal designs draw heat from water circulated underground or through piping immersed in lakes. Heat pumps can be effective even in cold locations, though they are sometimes paired with a backup heat source for exceptionally cold temperatures.

Water heating also can be a significant source of Scope 1 emissions. To reduce these, districts can install time-tested rooftop thermally absorbent water piping. Manufacturers have developed hybrid heater tanks that combine heat pump technology with electric resistance heaters. These draw heat from the air and concentrate it in the water. Because heat pump water heaters exhaust cool air, they significantly cool the rooms in which they are installed and require adequate space.

Districts can address cooking-related Scope 1 emissions by replacing gas stoves with induction cooktops. This technology works by magnetically inducing heat in the bottom of metal pots and pans. These stoves are quicker to heat and more efficient than resistance coil stoves but also more expensive. They are expanding into the industry because they provide precise temperature control with no emissions and fewer hot surfaces. Induction cooktops require magnetic pans.

Scope 2

Scope 2 emissions are those created indirectly by purchasing energy. Usually, this is electricity but could be steam if piped for heating. These emissions originate by turning on a light, for instance, drawing electricity from the grid. Utilities balance demand by running generators elsewhere on the grid. If they burn coal, significant carbon emissions will be produced. Alternatively, balancing with a hydroelectric dam or solar array will create virtually no carbon. These complexities make it difficult to quantify the carbon emissions associated with any specific amount of electricity. However, Scope 2 emissions can still be eliminated in other ways.

Conservation is the first choice for districts lowering their Scope 2 emissions. Every way to use electricity represents a way to save it. High-efficiency LED lighting produces far more lumens/watt than fluorescent lighting while improving quality and reducing maintenance. Districts can purchase ENERGY STAR appliances and automate energy-saving features of electrical devices such as computer monitors and room lighting. This saves electricity without requiring user behavior change. Building HVAC controls can be optimized for time and day of occupancy.

Solar panels and wind turbines are Scope 2 solutions that many school districts have installed. These generate zero-carbon electricity and can provide educational side benefits if generation is displayed for students. Rooftop solar is common but requires good sun alignment while complicating roof maintenance and replacement. Alternatively, panels can be installed over parking lots, providing welcome shade for employee cars. Ground installations allow easy access for maintenance, but take up real estate, require vegetation management, and might require fencing. Districts that install these energy sources may be eligible for local and state incentives and are likely to recoup investment costs within a handful of years.

These methods will reduce a district’s Scope 2 emissions, but to get to zero, districts must procure 100 percent of their electricity from zero-carbon sources like wind, hydro, solar, or nuclear. Multiple states have enacted laws requiring utilities to provide only carbon-free electricity by some cutoff date. Districts in those states have the problem solved. Others may be able to contract with a utility for the same service, as some offer “green power” programs promising to match customer purchases with an equal amount of renewable generation. Districts with neither of these options should lobby their legislatures to expand their low-carbon electricity options.

Scope 3

Scope 3 emissions are indirect carbon emissions that result from our operations but are outside the definition of Scope 2. Most items we purchase, from office supplies to food, created some carbon emissions during manufacture. These “embedded” emissions are essentially the Scope 1 and 2 emissions of our vendors. Business travel and employee commuting emissions are also Scope 3. For many organizations, Scope 3 is the largest category of emissions.

These emissions are extremely difficult to inventory. Fortunately, as world economies turn toward renewables, supply chains are greening up on their own. Still, boards have policy options for accelerating Scope 3 emission reductions, such as prioritizing green products in purchases, buying locally, encouraging repurposing and recycling, promoting remote work, persuading families to use school buses, and installing EV chargers for employee use.

School boards might understandably hesitate to take all this on. Climate change seems fraught with political overtones, detracting from immediate concerns like youth mental health, declining test scores, and staff retention. Yet, of these challenges, only climate change has a timer: The longer we wait, impacts worsen, and solutions become harder.

Educating children remains our primary mission, but how we do it matters. Young people have asked us to make a difference on climate because they know they will bear the heavy consequences of a too-hot, too-humid atmosphere after we are gone.

Do what’s easy first, but get started! Each school district will have its own optimum path to zero emissions. A district with old vehicles might find bus electrification a natural place to start. Districts in building programs should incorporate zero-emission concepts. I urge you to firmly commit to decarbonization, whatever the path. Set zero as your goal and 2050 as your deadline. Write this into policy.

Fortunately, carbon elimination is an investment program that will reap tremendous co-benefits in public health and operating budgets. Every level of government, every business, and every residence faces these same realities and can expect to implement similar solutions. Let’s get it done.