Region One could follow Hotchkiss lead on energy plant

LAKEVILLE — The Sharon Energy and Environment Commission is taking the lead on trying to persuade local towns and schools to convert to the new, efficient system of energy production now in use at The Hotchkiss School.

Hotchkiss (an independent co-ed boarding school for grades nine to 12) is on a quest to be carbon neutral by 2020. As part of that effort, the school spent roughly $14 million to build a biomass plant that provides heat for most of the campus (an area that is in excess of a million square feet).

On Friday morning, July 24, committee members met in the Mars Athletic Center’s parking lot and were joined by Sam Herrick, business manager for the Region One School District; Frank Perotti, who is on the Standing Building Committee for Housatonic Valley Regional High School; and Steve Hassig, head custodian for Sharon Center School. 

Committee member and Sharon resident Roger Liddell led the tour, along with John Tuke, who is Hotchkiss’ chief financial officer, and Dave D’Andrea, the school’s senior engineer. 

The tour began in the athletic center, with a visit to the two massive oil burners that were installed there about 15 years ago. They were used in summer, mainly for the swimming pool and “domestic hot water” uses such as washing machines and the showers in the locker rooms.

Those two units are now used only for back-up. 

The work they used to do is now mainly done by a diminutive and very efficient machine called the Ilios heat pump, which is about the size of a medium  household closet. 

The water heater is powered by a modified Ford Taurus engine that runs on about $10,000 of propane per year (compared to about $30,000 worth of heating oil that was needed to run the two boilers). 

Liddell said, “This is not ‘heroic’ technology. It’s a car engine.”

“And it’s very small,” said Sharon Energy and Environment Committee member Kathleen Fuhr. “Could you find a place for this at the high school?”

“We could find a place for this,” Herrick said.
“And it’s in our capital plan to replace the boilers there.”

The heat pump is only used in summer and the shoulder seasons, when the central biomass plant is turned off (in April) and until it is turned on again (in October).

The group then went over to take a tour of the biomass facility, housed in the wavy-topped building off Route 41, beside the golf course.

Tuke explained that the decision to build the new facility was made because the school’s old central heating plant “was at the end of its life.”

It was also located next to a dormitory. The school decided to see this as an opportunity: It could build the most efficient possible plant and site it in the most intelligent location.

After extensive research, the school decided to build a biomass facility that burns wood chips. 

D’Andrea said, in response to a question, that wood pellets are a little easier to store and handle than wood chips but they’re also more expensive and they are sometimes treated with chemicals. 

Wood chips are simpler, cheaper and cleaner. The school has several suppliers of chips, but one of the major vendors is J&J Lumber in Dover Plains, N.Y. 

The chips cost, on average, $41 a ton. A single ton has a BTU output that is equivalent to 59 gallons of No. 2 heating oil. The cost savings equal about $600,000 to $700,000 a year, Tuke said.

When asked why the small and efficient water heat pump is not used all year, D’Andrea said, “The water heater uses propane, which is more expensive than the wood chips.” 

“And you can’t use that little heat pump to substitute for the wood-fired boilers and the chillers needed to cool the hockey rinks,” Tuke said.

The decision was made to put the plant in a very central and also very visible location, not only because it efficiently connects all the buildings but also because, Tuke said, “it’s an educational opportunity.”

Centerbrook Architects, an award-winning firm based in Essex, Conn., designed the plant (as well as  the school’s Katherine M. Elfers Hall and Esther Eastman Music Center).

The facility itself doesn’t require a beautiful exterior, Tuke noted, but “the school chose to make the investment in an esthetically attractive building given its prominent location and because we view it not just as a heating plant but as a classroom.”

He estimated that the technology for the biomass facility cost about $3 million. The other costs were for pipes to carry the heat throughout the campus, and for the design and construction of the building. He also estimated that a traditional central heating system would have cost about $11 million.