Lexington’s new high school is poised to cost about $660 million, but a chunk of that cost will go toward green technologies that will eventually start paying for themselves.
Lexington plans to invest in a 4,806 kW system of solar panels, a 2MW / 8MWh solar energy storage battery, 20 electric vehicle chargers, and hybrid air-source and ground-source heat pumps for HVAC, according to the schematic design the building project team submitted to the Massachusetts School Building Authority last month.
The up-front cost of that HVAC system is cheaper than a traditional gas boiler, and the state and federal governments are likely to grant Lexington reimbursement for choosing the environmentally friendly option. The cherry on top of the cake? Lexington will likely produce more energy with its solar system than it will use and Eversource will credit the town to tap into it.
“It almost turns out to be like a miracle win for everybody,” Select Board member Mark Sandeen, who is also president of MassSolar is Working, a Lexington-based nonprofit that works to make solar accessible, told LexObserver.
Upfront costs
The miracle isn’t all in the credits and rebates Eversource could grant Lexington for its solar, however. Most of the savings come from cost avoidance, Carolyn Kosnoff, Lexington’s assistant town manager for finance explained to the Observer.
Lexington’s Fossil Fuel Free bylaw and Specialized Energy Code state new construction in town must be all-electric to avoid burning fossil fuels, which are harmful to the environment. The town can’t, therefore, go with a traditional gas boiler and air chiller system that most schools built before 2020 have.
Lexington instead plans to install a hybrid air-source and ground-source heat pump to heat and cool the new LHS, which does not burn any fossil fuels and is more environmentally friendly.
The hybrid air-source and ground-source heat pump the town is planning to move forward with costs about $62.2 million, which is roughly $10 million cheaper than a traditional gas boiler and air chiller, Sustainable Lexington, the group vetting the green technologies, found.
The hybrid system also requires less maintenance and has a longer lifespan (so it will need to be replaced less frequently) than the traditional fossil fuel option.
On top of the lower upfront cost, Lexington predicts MassSave, the state’s energy efficiency program that offers incentives for reducing energy use, could give the town between $4 million and $5 million for installing heat pumps.
Lexington is also holding out for about $10 million from Washington for installing the heat pumps and a solar battery. While President Donald Trump has massively scaled back on Inflation Reduction Act rebates, the administration is still offering incentives for geothermal heat and solar storage.
As for solar, the town expects to make annual payments of just under $1 million for 30 years. But at some point, the return on that investment could be significant.
Sustainable Lexington predicted the town could save about $90 million (in upfront cost savings, maintenance fees, replacement costs, state and federal grants, and some extra change from Eversource for tapping into the battery) over 30 years.
How the solar money-maker works
If it’s sunny outside while school is in session, LHS will run on energy generated by its solar panels, which will greatly decrease its Eversource bill.
Commercial facilities such as schools pay a monthly usage bill, like residents do, and a peak demand charge. A peak demand charge is a charge for the highest amount of electricity used in any fifteen minute period during a given month on a kW basis.
It’s as if you had to pay for the top speed that you drove your car each month. If you hit 95 miles per hour while driving up to New Hampshire last month and that’s the highest your speedometer got in all of August, you’d pay a peak demand charge for that 95 miles per hour speedometer reading. In the case of schools, a municipality is charged for a school’s top kW usage for the month.
Lexington’s current high school’s peak demand charge equals about half of its entire energy bill, Sandeen said. The battery could help cut that cost significantly.
“When I turn on my heating system or my air conditioning system…the battery discharges so Eversource doesn’t see that peak demand,” Sandeen explained. “We can have, for example, a peak demand of 1.5 MW, but the battery could make it 0.3 MW…so now I can cut my bill dramatically.”
But what happens when it’s cloudy? Or raining? Or snowing?
When school is not in session, like on the weekends, during the summer, or even after school before the sun goes down, the school uses less electricity than when school is in session. At those times, the solar panels continue to generate energy and store it in the battery.
When it isn’t sunny outside and the solar panels don’t generate enough energy to power LHS, the system will use the battery for electricity.
Even if Lexington has a bunch of rainy and snowy days, the battery will still hold a surplus of power. The town can sell that extra energy to Eversource for others to use in exchange for credits.
“During the summer months, when everybody’s air conditioning is cranking at maximum, they’re worried about brown outs, and [Eversource doesn’t] have enough electricity to pass around to everybody, they’ll send a little trigger to Lexington High School and say, ‘it’s super hot out, we need to trigger you,’ so we’ll discharge our battery to the grid and they pay us for that,” Sandeen explained.
How do we know we’ll make more than we’ll use?
Lexington’s design team on the high school building project modeled what the school will use for electricity during every hour of the year. They added those numbers up and estimated what the school’s energy usage could look like.
That model predicts LHS could use about 20,000 BTUs per square foot per year, or about 26 energy use intensity (EUI). Even if the school uses 30 percent more than that, the solar and battery will still be able to help support the school and supply Eversource with some extra energy in exchange for credits, Sandeen explained.
“People are, understandably so, worried about the cost of this project,” Cindy Arens, chair of Sustainable Lexington, told the Observer. “If we’re talking about being financially responsible for the town’s finances, it would be irresponsible not to do this.”
EV chargers
The town is also investing in level-two electric vehicle chargers for 20 of the parking spaces at the school. Level two chargers are high-power chargers that provide vehicles between 25 and 32 miles of range per hour of charge. Users will have to pay to hook their cars up to the EV chargers that will be at the school.
The town anticipates electric vehicles will become increasingly popular in the near future, so it plans to create the infrastructure to install more EV chargers as demand increases over time.
Environmental pros
All this green technology will not only save the town money, but it will save Lexington in other ways, too. These investments will help chip away at Lexington’s carbon footprint and improve the health of LHS students and staff.
Buildings contribute to about one third of the state’s carbon emissions, Meg Howard, program director for the Massachusetts Clean Energy Center’s high performance buildings team, told the Observer. Making Lexington’s largest-ever capital building project all-electric is a meaningful step in reducing the town’s carbon footprint.
And the new HVAC system will regulate the air quality inside the building which can help keep students and teachers healthy, Arens said.
“Even if we had no outside pollutants, no airborne diseases, even just packing students in and we’re all breathing and giving off [carbon dioxide] — you need extra oxygen,” Arens said. “The better the air quality you can make sure you have in your building, students get higher test scores, staff is more productive…less people are out sick, so it’s good for so many things, not just the environment.”
Some residents have expressed worry about the battery because it is a lithium ion battery, which produces about 3,000 metric tons of carbon emissions to be created (by mining and refining the lithium inside the battery) and installed. But Lexington will save about that much in the first year of the system working alone, Sandeen explained.
What’s next
Lexington’s SBC has recently started doing what’s called ‘value engineering’ with the project’s design team. Value engineering is when the project team further analyzes the design and discusses where they could cut costs.
Sandeen and Arens hope the SBC does not cut back on its green technology plans because doing so would increase taxes for residents later.
“There are things you can do to cut costs that will increase your operating costs later,” Sandeen said. “If we cut the solar now, you’re going to be paying for it later.”
All the envisioned green features proposed for Bloom could equally be included in a renewal of the School on the present campus. It only requires the interest and thought to do it. SMMA opened that door with its plan C6 in April 2024. They praised its ability to address overcrowding in 1/2 the time as Bloom. And protect the center park and playgrounds, avoiding chapter 97 challenges. It was never given fair consideration. Well, what could we expect when it was posted on the website of frequently ask questions in September of 2022, a full year before a design team was hired, that said “the general idea is for the students to remain in the old (current) LHS while the new building is being constructed”.
The idea of destroying the value of the connectivity of Lexington’s center recreational complex could only come from ones who never benefited by watching their children in different sports. Parents who have had children play little league and soccer while watching younger siblings play at the playground understand.
Lexington should never break the contract made in 1915 between the Town and Augustus Scott when Augustus, a true unsung hero of our Town, gifted 30 acres for the perpetual use as parks and playgrounds to all of Lexington’s citizens.
Peter (or anyone else):
Can you give us a link to what “C6” was? I ask because my query “show me the C6 concept SMMA proposed for Lexington’s new high school” on Google’s “AI Mode” yielded:
SMMA did not propose a “C6” concept for Lexington’s new high school. The firm, acting as the architect for the building project, developed and presented a series of conceptual designs, or “massing studies”. The design the School Building Committee (SBC) ultimately chose to move forward with was officially known as massing study C.5b, and was nicknamed “Bloom”.
But I find AI generally “stupid” and I don’t recall ever seeing a “plan C6”, therefore my question. Thanks!
I found C6 on slides 52-54 of https://drive.google.com/file/d/1I24k7Q-t5jitAcGj40gtPmbYKxPhAhy-/view.
In April 2024 C6 cost $612 million (including $12 million for modulars), or LESS than C5B, later renamed Bloom, which cost $618 million at the time (slide 57).
And C6 is curved (like Bloom), so more expensive than a simple “box” replacing LHS’s foreign languages building as Phase 1 of a “true 2-phase design” would be. So C6 is unnecessarily expensive, and if phased properly, could require fewer modulars, making a true 2-phase design possibly far less expensive than Bloom.
Bottom line, the SBC NEVER looked at a true 2-phase design that would cost less than Bloom and would accommodate far more students than Bloom’s 2,395.
We have been kicking this can down the road for 20 years!! That’s why it’s so expensive now. We need a new, modern high school NOW. We have been patching it up ever since my children were at LHS in the early 2000’s. Those who are sentimental about the past would do well to look to the future and give our children the modern, safe high school they deserve for the 21st AND 22nd century.
Masha:
Yes, absolutely correct.
But the SBC proposes Bloom, slated to last 70 years, but sized for only 2,395 students, FEWER than we had last year, while Lexington’s population may INCREASE by 30% once all new https://docs.google.com/spreadsheets/d/17OpIfyFsvGyrz8u_fQ5nhWYk7rnEDml4/edit?usp=sharing&ouid=116971253884586510151&rtpof=true&sd=true MBTA developments are built and occupied in 8-10 years from now.
So Bloom would waste $660 million. A better design is possible, which the SBC has so far stubbornly refused to consider.
This is a great article – I learned a lot! Thank you for doing all this research and sharing!
I appreciate that Lexington has a local newspaper covering important community issues like the new high school project. That said, this particular article misses the mark and reads more like a promotional advertisement for the school design than balanced reporting.
The number of times the words “could”, “likely” and “expects” appear in connection with savings should raise red flags. These projected benefits are entirely untested, highly uncertain, and come at an extraordinary upfront cost. There is little hard evidence that the financial payoffs will ever match what is being suggested here.
I’m also concerned about the repeated reliance on Select Board member Mark Sandeen as the primary voice of “expertise.” Mr. Sandeen is well known for his obsession with solar and willingness to spend taxpayer money on it — yet he doesn’t even have solar installed on his own home. That inconsistency deserves to be called out rather than overlooked.
The community deserves a clear-eyed, fact-based assessment of costs, risks, and alternatives, not a one-sided story that assumes everything will work out as promised