From competitive sports to recreational activities in the winter (i.e. ice skating), hockey rinks are found across North America and with expanding economic powers like China beginning to construct ice rinks, energy consumption by sporting events is poised to increase. Ice rinks in general are energy hogs in somewhat obvious mechanisms of pumping coolant and refrigeration. However, major inefficiencies can be found in older systems regarding a less obvious measure – heating. In order to keep spectators comfortable, ice rinks will often keep air temperatures closer to 60°F.
This is unsurprisingly, not the best method to keep ice at optimal conditions. Even simple changes like reducing air temperature from 60°F to 40°F have been found to provide energy savings of 25 to 50%. Touchstone Energy even claims that adding a heat recovery system to an ice rink can realize up to 75% in energy savings. Theoretically, waste heat from the refrigeration condenser could be used in domestic water heating, subfloor heating, floodwater heating, ice melting, and preheating cold outdoor air for ventilation. However, many older rinks are in arenas that cannot undergo such upgrades to facilitate these uses at a feasible cost.
Above: ASHRAE comparison of rink energy consumption by percentage.
It’s not all gloom and doom though as the National Hockey League (NHL) at the professional level and a multitude of community rinks at the local level have shifted towards using more energy efficient means. While these are still in the developing stages of getting to a net zero status, the methods are wide ranging and can be used as case studies for future rinks. Harold Mayhew, an architect who specializes in skating rinks finds himself on the forefront of making ice rinks more efficient (and more recently with the goal of net zero). Mayhew designed the ice rink at Maine’s Bowdoin College, which opened in 2009, that became the nation’s first hockey rink to be LEED certified. He is currently undertaking the task of moving Woodstock, Vermont’s Union Arena toward the lofty net zero goal. Beginning in late 2016, the arena is upgrading the existing equipment, finding ways to reuse waste heat from the compressors, and buying solar panels to chip away at the energy bill that almost contributed to the rink potentially folding. Early efforts have already dropped the monthly energy consumption by 12.5% compared to the same time period in the previous year.
A couple of other interesting rink upgrades are also found up north. Falmouth High School in Massachusetts has installed around 4,400 solar panels on the roof of the rink and in a nearby parking lot that add up to about 1MW of capacity to cut down their utility costs. The Marcel Dutil Arena in Quebec trail-blazed their rink upgrades by going to a 100% CO2 – based refrigeration system (uses CO2 as the working fluid). By using CO2 the arena avoided the need for a secondary working fluid and saved energy in the design by not needing large pressure inputs into the system to chill the ice. More traditional rinks use ammonia or Freon chillers, and glycol or brine as secondary fluids.
Above: Falmouth Ice Arena’s solar array can provide power of about 1MW in capacity to help cut down on utility costs (this is enough power for around 164 homes).
The NHL Green initiative was a major push by the league back in 2011-2012. Big pushes on social media fronts established that the NHL was looking to be the face of professional sports going green. Ultimately, the league has made strides since then, but maybe has not become very well renowned for its efforts. The NHL boasts that it is the “1st professional sports league to issue an environmental sustainability report” and the “25th largest user of green power in the United States,” among many other commendable measures. That being said, the league still emitted 408 metric tons of CO2 per game in 2014. While this is a slight improvement from around 416 mtons back in 2011, that is still an annual emission of 528,322 mtons CO2. This would seem miniscule to Plant Scherer (coal power plant) in Juliette, GA whose emissions were 17.7 million mtons in 2016, but then again Scherer is generating electricity that may very likely be powering ice rinks in the state (the old Macon Centreplex in particular).
Above: The NHL according to their 2014 Sustainability Report indicate that they are working to mitigate their current emissions that add up to 55 pounds CO2 emissions per sq. ft.
As a caveat, Mayhew said in discussions with people who work in the ice rink industry across the continent and beyond that no one is aware of any other facility looking to make their energy bill completely zero. Ultimately, the electricity bill will eventually force the hands of many establish rinks. From building construction to upgrading lighting to optimizing ice thickness, there are several areas where improvements can be made. The following quote from Mayhew sums up the situation quite nicely “If you can make a hockey rink a net zero building, you can make anything net zero.”
So what does everyone think? Are upfront economic costs the main driver as to why we do not see wholesale changes happening in ice rinks? Or is it more of the rink managers not researching proper methods to save money? Are there other aspects of ice rinks you believe could be looked at either at small community rinks or at large city arenas?
Sources and Further Reading:
Managing Energy Costs in Ice Rinks:
World’s First CO2 Ice Rink:
Ice Rinks vs. Energy Bills:
Union Arena and Sustainability:
NHL Green – By the Numbers:
NHL Green – 2014 Sustainability Report:
Plant Scherer Emissions: