Almost three years ago, the first steps were taken to cut the amount of energy used at Waupaca High School.
In April 2008, Harley Hellerud, who was then the school district’s business manager, began working with Focus on Energy’s representative, Don Keck, to look at what was needed to cut the school’s electric bill.
During the period of April 2007 through March 2008, the number of kilowatt hours (kwh) used at the high school totaled 2.8 million with an average of 234,567 kwh per month.
The high school’s electric bill averaged $17,767.63 per month during that same time period.
Around that same time, Glenn Flatoff was hired to be the school district’s new director of building and grounds.
“It took seeing the electric bills,” he said. “I saw (the equivalent) of a new car being spent every month at one school.”
Within a year, more steps had been implemented at the school.
As a result, the number of kwh being used at the high school has decreased from a total of 3 million kwh for the period of April 2003 through March 2004 to 1.7 million kwh for the period of April 2009 through March 2010.
During the last year, the average number of kwh used at the high school was 111,300 kwh per month. The school’s average monthly electric bill was $12,274.59.
Back in April 2003 through March 2004, the average number of kwh used per month was 251,933, and the average monthly electric bill was $13,073.
Some may wonder why such a large reduction in the number of kwh used at the high school has not resulted in an even larger decrease in the school’s monthly electric bills.
Flatoff said that between 2005 and 2007, the electric bill’s rate increased a total of 32 percent, “so our WPS bill (at the high school) would have been considerably higher today if these steps had not been taken.”
He said, “The school district had been working with Focus on Energy prior to when I came here. The major thing then was them changing out most of the 450-watt metal halide light fixtures and replacing them with higher efficient fluorescent fixtures in the gyms in all the schools and in a few additional rooms at the high school.”
He found ways to save more energy.
“I came in and basically continued carrying the baton one step further by aggressively programming the HVAC and lighting schedules and also by utilizing newly installed load limiting features on the high school building’s chiller systems.” Flatoff said.
That can best be described as another phase in the school district’s plan to cut energy usage at the high school.
The next step involved the addition of a condensing boiler in September of 2009.
“We added a smaller condensing boiler to the existing three large boilers so we can automatically reset the boiler’s hot water supply temperature to lower temperatures on milder ambient days, thus using less gas to heat the same quantity of the system’s water. And, because of the new boiler’s smaller size, we can better match the building’s lighter heat loads, thus reducing short cycling that was prevalent with the larger boilers,” he said.
Flatoff explained that with non-condensing boilers, the temperature of the water must be kept at a minimum of 160 degrees. The addition of the condensing boiler allows that water temperature to be reset to about 120 degrees, depending on the outdoor ambient temperatures.
The cost of the new boiler including installation was $64,500. Because this project was combined with other energy reducing projects at the high school at the same time as the boiler addition, the school district received a $29,500 Focus on Energy Grant for the boiler project, with the district’s cost then being a net of $34,950.
In 2007, the total number of therms used at the high school was 119,145.
That number was 102,305 in 2008. In 2009, which is the year the condensing boiler was purchased, that number totaled 89,059, and in 2010, which was the first full year with that boiler, the total number of therms used at the high school was 63,751.
The heating bills for the high school have also dropped from $117,572 in 2007 to $54,419 in 2010.
“But the whole key and the biggest savings energy are realized by simply shutting equipment off when it’s not needed; whether it’s lighting, HVAC equipment or anything else for that matter,” he said.
While the high school’s main hallway lighting used to be divided into only two main zones, one of those two zones was divided, resulting in three zones to control at the school.
“So, this way we can shut off a lot of lights that weren’t necessarily needed,” Flatoff said.
At 3:30 p.m., the high school’s hallway lights go off and HVAC system goes into the night setback. The temperature at the school is 62 degrees at night, compared to approximately 68 degrees during the school day.
Flatoff, using an installed on-line based computer HVAC and lighting program, is able to make various adjustments including scheduling in all the school building’s HVAC equipment and some of the high school’s lighting systems (exempting classrooms).
And, he says there is more that can be done at the all the schools.
More efficient lighting is available. “Lighting in the classrooms will be the biggest things,” he said.
Since members of the high school’s Green Team talked about sustainability during a recent in-service day at the school, some teachers have already been turning on less lighting in their classrooms.
Flatoff sees finding ways to save the school district money as being part of his job.
“This will be an ongoing pursuit for me for all the buildings belonging to the school district. And, as a basis, I plan on using many of the recommendations provided by Don Keck as a general guide for any other future projects. Don’s consulting has been an invaluable asset to this endeavor,” he said.