JAY — Seedlings are growing in a greenhouse at the Jay Middle School, thanks to the work of some physics students.

“Nothing has ever grown in here. Look at what we have done,” Joe Roy, a high school senior in Rob Taylor’s physics class, said Tuesday as he and three others walked into the greenhouse.

When he was younger and in that school, Roy said, he remembered people trying to grow things and they couldn’t because of excess heat.

It was way too hot during the day and too cold at night, he said.

“We almost died when we walked into it the first day,” student Devin Rose said.

Students conducted experiments in March and found that the peak temperature was 118 degrees, Roy said.

Taylor assigned his physics students to do a research paper on why it was too hot and to solve the problem without using electricity.

“First, we had to figure out why the greenhouse was so hot,” senior Miles Hutchinson said. “We had to research thermodynamics.”

They decided the main reason why the greenhouse was so hot was because of radiation, he said.

Sun rays coming through the windows produced the radiation, Nick Raymond, a fellow senior, said.

The class then researched different ways of transferring the heat. They explored ventilation, reflective and filtering surfaces, thermal mass and humidity control.

The students decided on a thermal mass heat-transfer system.

The way it works, Roy said, is water absorbs the heat in the greenhouse during the day and at night, the water releases heat into the air.

They decided to use seven, 40-gallon buckets and nine sauna tubes full of water.

When they added the water, the temperature in the greenhouse doesn’t go above 100 degrees during the day, he said.

And, it doesn’t drop below 65 degrees at night, Raymond said.

A rule of thumb, Hutchinson said, is a minimum of two-thirds of a cubic foot of water per square foot of south facing glass is needed to regulate greenhouse temperatures.

They really needed to use 16 more buckets of water to keep the temperature constant in the room, he said, but there was no space in the greenhouse.

They compromised by using less barrels of water and placing the plants on a wooden shelf on the barrels.

“It’s a very simple passive solar system,” Taylor said.

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