Whenever I interview anyone for a story on Re-Surfacing.com, I always ask what else they’ve done that’s special at their arena! When I asked Scott Currie from the Abbotsford Arena (harvesting rainwater to build and maintain ice) he said I should talk to Brian Skow at the Angel of the Winds Arena in Everett, WA. Brian, he told me, covers his ice with a thermal blanket as a way to save energy and run time. He’s even tracked his results — and would probably share them with me.
The Angel of the Winds Arena is an entertainment destination with twin ice pads that act as the home and practice ice for the local major junior hockey team, the Everett Silvertips of the WHL. Run by Spectra Venue Management, the facility’s operations team is adept at event-to-hockey conversions for everything from singers and bands to home shows and monster trucks.
The practice pad is always busy but there can be long breaks in the schedule where the stadium ice sits idle, sometimes for hours or days at a time. Despite no action on the ice, the ice plant still kicks in to maintain the ice temperature. Every time the compressors are called on for idle ice, the arena is burning money. Brian Skow had an idea. Why not cover the ice with a thermal blanket to keep the cold in, and the warm out? Skow turned to Innovative Insulation Inc. out of Arlington, TX — the largest manufacuturer of radiant barrier products in the world — to supply him with enough Tempshield Double Bubble Foil to cover the ice. Costing $4,000, in January, 2014 they started to “tuck in” their ice with the foil blanket. They also tracked what happened with their ice plant.
Four months later, their energy savings had already covered the costs of the foil blanket.
Radiant barriers and reflective insulation are now common in practically every type of building construction, but this is a 70-year-old idea that was blocked for years from gaining traction in the marketplace. The deep-pocketed insulation manufacturers with fibreglass, rockwool and cellulose offerings wanted to protect their markets. Soliciting the help of lobbyists and construction organizations, they were adept at keeping the pesky radiant barrier manufacturers from grabbing too much of their market share. But that began to change because of America’s involvement with the space race.
Beginning with the Gemini program, NASA developed radiant barriers to protect their equipment and personnel who had to face temperature swings of more than 500°C. To do that, they turned to aluminum foil’s reflective properties to prevent flash-freezing or -melting their rockets, on-board instrumentation, and most importantly, space and moon-walking astronauts. Soon, architects and engineers began to spec reflective barriers and insulation in their projects. Universities and government organizations studied and confirmed the claims and today radiant barriers and reflective insulation are construction standards. For a more in-depth history of radiant barrier, find out more on the RadiantGuard website.
The graphs below compare the slab temperature trends with and without the Tempshield Double Bubble Foil covering the ice. The downward slopes on the trends indicate when the brine pump, compressors, etc. are running to keep the ice cold. The upward slopes indicate when the temperature set point is satisfied, and the brine pump and compressors are no longer working. Note: the practice sheet is blue and the main sheet is aqua.
The next graphs are with foil on the main sheet, and no foil on the practice sheet. Notice the reduction of equipment run time on the covered sheet compared to the uncovered sheet. As a reminder, the practice sheet is blue and the main sheet is aqua.
Sheets and Blankets
What about cost?
Each downward slope equals about $9.00/hour. Look at the second-last graph and you’ll see that over a 12-hour period, the uncovered sheet actually ran its part of the system for around 6 hours (or about $54.00). The covered sheet, however, ran just over 2.5 hours, costing just $22.50 — a 58% reduction in energy costs.
But there are other factors to consider apart from energy savings.
Less equipment run time means less wear and tear and extended maintenance intervals. So any time you’re saving 3.5 hours of run time over a 12-hour period, you’re pushing scheduled maintenance further down the calendar.
There are personnel costs to consider as well.
Skow says his foil blanket takes about 20 minutes for 2 people to lay down and about 30 minutes for 2 people to pick up. For his facility, he needs a 12-hour coverage block to make the set up and tear down cost effective.
“If the ice sheet has a full day or multiple days of idle time, it’s well worth using the foil,” he says.
When the foil is all rolled up, it can easily be stored on 2 carts.