By Matt Menard, Market Manager - Air Conditioning
Here in New England, it’s the beginning of spring and the bittersweet end of college basketball. And here at ebm-papst USA’s Farmington, Connecticut headquarters, we’re so proud of the UCONN men’s and women’s recent NCAA Championship wins!
While March Madness describes the NCAA basketball tournament, it’s often an appropriate description for the mechanical systems at large sports arenas in spring and summer. As I watched college teams play through the bracket this season, I also marveled at how — as temperatures in the arenas rose and fell — these systems kept pace with fans’ and players’ comfort.
Controlling the HVAC Nightmare: The Basics
Arenas have everything working against energy efficient HVAC operations. Most of the time they are empty with the lights off, requiring very little heating or cooling. Within a matter of hours, they are filled with athletes, media, employees and thousands of fans. Extremely bright lights are turned on, emitting enormous heat loads. Hundreds of cooking devices begin cooking food for concession sales. Then, within a matter of hours, the arena is back to dark and empty.
The HVAC systems installed in large arenas need to be designed for worst-case scenarios. For example, a college basketball powerhouse arena in North Carolina would size its HVAC system for 10,000 people. How does this same university operate its system efficiently when the team is practicing in January?
In arenas where the cooling (and heating) load can fluctuate so drastically, a well designed and commissioned building automation system is the key to efficient operation. Event scheduling and well placed temperature, occupancy and humidity sensors will allow for the system to perform where and when it needs to, ensuring efficient operation and a well-conditioned arena.
Designing and Installing an Efficient System
Whether the arena is being built new or going through an upgrade, focusing on the efficiency of the entire system is key. The design team should focus on how the entire system operates at full and partial capacities, sizing and selecting components that complement one another throughout the range of operation. Simply selecting the most efficient individual components does not equate to the most efficient system.
Utilizing Speed Controls
A 98-degree arena holding 10,000 screaming basketball (or hockey) fans in late spring or summer would result in a 100% load on the HVAC system. However, when the team is practicing in January, the load may be as low as 10% of that system’s design capacity. By utilizing speed controls such as variable frequency drives for pumps, cooling towers and chillers and EC fan technology, such as ebm-papst backward curved impellers on the air movers, sports arena managers can save enormous money on their utility bills.
“Free” Cooling and Heating
There are many ways to heat and cool without boilers or air conditioners that well designed systems can use to save money:
Airside economizers: when cooling is needed and it’s 15 degrees outside, why not mix in the 15 degree air to achieve the needed cooling?
Waterside economizers: same as airside—when it’s cold out, don’t run the chillers! Use heat exchangers to chill the water using the air that’s just outside!
Heat recovery: direct ‘waste’ heat from chillers, boiler flu stacks or exhaust air to preheat the domestic hot water before it enters the boiler system.
Years of trial and error (combined with the latest technologies) have taught us that the energy bill for sports arenas doesn’t have to be out of control – not as long as long as these systems are designed, operated and updated to adapt to varying schedule and heating/cooling loads.
About Matt Menard
Matt Menard lives for the chill. With 12 years’ experience in HVAC systems, the market manager – air conditioning at ebm-papst actively supports designers’, manufacturers’ and integrators’ quest for cooling Nirvana with a wide range of air-moving products. With a BS in Mechanical Engineering from Rensselaer Polytechnic Institute, Matt enjoys skiing, golf and spending time with his wife and two children.