SCARBOROUGH — A new control system will ensure the hydraulic fluid in 16 Public Works trucks is kept warm in freezing weather, while saving the town an estimated $18,000 or more per year.

The $11,000 price tag for the control system and installation was covered by a portion of the $84,300 in American Recovery and Reinvestment Act funds allocated to the town in May through an Energy Efficiency and Conservation Block Grant program.

Under conditions of the grant, the town must use the funds on projects that would reduce its fossil fuel emissions, reduce total energy use of the eligible project, improve energy efficiency in transportation, building or other areas, and create jobs.

Housed in an exterior-mounted electrical box, the new system automatically turns on the trucks’ block heaters to warm the hydraulic fluid when the outside temperature drops to 32 degrees, Director Mike Shaw said. Between 20 and 32 degrees, the system cycles the heaters on and off to keep the fluid warm without continuous use of electricity. Below 20 degrees, the system runs the heaters continuously.

Before the new system, the 1,500-watt block heaters used on eight of the trucks and the 4,200-watt combination block and oil tank heaters used on the other eight were turned on in mid-October and remained in constant use until mid-April.

First proposed by master electrician and contract worker for the town, Don Mitchell, the system is similar to one he installed a few years ago for school buses. But Mitchell said that project was easier because it operates with a simple timer that kicks the heaters on in advance of each morning’s bus run.

But, unlike school buses, it’s difficult to predict exactly when plow trucks will be needed. Sometimes, sudden icy conditions require an immediate response. And before the trucks are taken out, the hydraulic fluid must be heated to prevent it from thickening in the cold, which hampers proper functioning of the plow and other movable parts on the trucks.

“When that fluid’s thick, the sander barely spins,” Operations Foreman Richard Collins said.

Sometimes new technologies can create new problems, Shaw said. In the case of LED traffic lights and truck headlamps, which are now being used in many communities to replace less-efficient lighting, saving money and reducing the carbon footprint has come at a price, Shaw said.

Since the new lights do not give off heat like the old ones, they cannot melt the snow that eventually covers them during a storm. Last year, Collins said, they were called on to assist South Portland Public Works to clean off obstructed street lights surrounding the Maine Mall. And plow drivers must also stop to clear their headlights at times during their work.

But Shaw said he is confident that the only change the town will see from the new technology used on the truck heater block control system will be savings to the bottom line.

Peggy Roberts can be reached at 781-3661 ext. 125 or proberts@theforecaster.net.

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Don Mitchell, left, and Scarborough Public Works Director Mike Shaw stand in front of a new system designed to turn on heaters that warm public works trucks’ hydrolic fluid when the temperature dips to 32 degrees or lower. The temperature-sensitive control system, obtained with $11,000 of an $80,000 energy grant recently awarded to the town, is expected to save more than $18,000 a year in fuel costs.