5. - 11. ICESR 08-14-2007 - Laserfiche WebLink

Home Browse Search

OPERATION AND MAINTENANCE IMPROVEMENTS *Increase Ice Temperature Many arenas can substantially reduce energy costs by increasing the average ice temperature. The ice sheet constantly absorbs heat from the warmer air and building around it and the rate of heat absorption naturally decreases as the temperature of the ice sheet goes up. Because the refrigeration system must work to remove the heat that the ice sheet absorbs, its energy use also decreases whenever the ice sheet temperature can be raised even slightly. The reduced heat absorption also reduces the amount of energy needed to heat the arena and the higher average ice sheet temperature causes the refrigeration system to operate more efficiently. Because the overriding concern of arena operators must be to maintain the ice sheet integrity, temperature controls are often set at a conservatively low value that will maintain ice sheet quality under the most adverse conditions. Because the ice sheet might be subjected to such adverse conditions for only a few hours, days, or weeks, a conservatively low temperature setpoint will keep the ice sheet colder than it really needs to be the majority of the time. Depending on an arena's schedule and refrigeration system, it may also be practical to substantially increase the ice temperature during long unoccupied periods (e.g. overnight and throughout the morning). Unless an automatic set-back control is used, adjusting ice temperatures may require daily, manual adjustments. Annual energy cost savings from increasing the average ice temperature only 1 °F range from $200 to $800 for asix-month arena and from $800 to $1,600 for ayear-round facility. Reduce Ice Sheet Thickness Control and reduction of ice sheet thickness can reduce energy costs while also providing more consistent ice quality. While the minimum acceptable ice sheet thickness varies somewhat from arena to arena, a typical optimal thickness is one inch or less for arenas with an even concrete base; arenas with a sand base may need ice at least two to three inches thick to provide adequate support for the resurfacer. Reducing the ice sheet thickness by one-quarter inch will allow the ice surface temperature to be kept the same while the coolant or slab temperature setting is increased bytwo-thirds of a degree. Increasing the coolant and slab temperatures saves energy by increasing the efficiency of the refrigeration system. Typical annual energy cost savings from increasing the ice temperature one degree (one-half inch reduction in ice thickness) are approximately $145 for asix-month arena and $300 for facility that operates more than 9 months. In addition to energy savings, closely controlling ice thickness also makes the quality of ice more consistent because the ice surface temperature is closer to the rink floor and coolant temperature. *Reduce Refrigeration System Head Pressure Controls Energy consumption in many ice arenas can be reduced by adjusting the refrigeration system's head pressure controls. The refrigeration system keeps the ice sheet cold by recirculating refrigerant. The refrigerant absorbs heat from under the ice sheet and then dumps that heat to the Possible low-cost/no-cost improvement Energy Improvements in Minnesota Public Ice Arenas Project page 1 Center for Energy & Environment