When a crowd of 71,088 witnessed the Denver Broncos confound experts and bookmakers alike by manhandling the Carolina Panthers 24-10 in the Super Bowl 50 on February 8, they were not only witnessing an upset in results but were also experiencing the latest and best in terms of environmentally friendly practices in stadium design and construction.
While the atmosphere was electric and mass amounts of energy were no doubt pumped out on the day, the Levi’s Stadium at which the venue was impressively green. An array involving more than 1,000 solar panels incorporated into the venue’s design is capable of generating sufficient electricity to offset not just the energy used on the big night but indeed that used throughout home games all season long.
With 85 per cent of the water being used for toilet flushing and irrigation, meanwhile, the lush green field posed no worries either. Finally, low-flow plumbing fixtures which use 40 per cent less water compared with conventional ones added further to the sustainability and efficiency of restroom facility design.
Thanks to all of the above plus more, the venue is the first professional American football stadium to achieve Leadership in Energy Efficient Design (LEED) Gold Certification for new construction.
Moves in this space are also afoot down under. In Melbourne, for example, the MCG Trust hopes to slash carbon dioxide emissions by 19 per cent and water use by five per cent as well as reduce utility costs by 20 per cent through an $8 million retrofit involving the replacement of light towers with low energy lighting technologies, new building management systems and chilled water systems, revamped heating and ventilation and modernised room control systems.
All this prompts interesting questions as to where the best opportunities lie and how some of the critical considerations regarding sustainable sporting and entertainment venues differs from that of more conventional residential, office or retail space.
Mike King, a principal at Arup who was the lead structural engineer on the Singapore Sports Hub Project which included the 55,000 National Stadium, says these types of venues are unique in terms of their irregular usage patterns, with many stadiums not being occupied on a nine-to-five basis as is the case with office and retail premises but instead being used intensively on infrequent occasions.
King said it was imperative to think about how the stadium could be integrated with other developments in order to maximise its range of uses. The stadium in Singapore, for example, was integrated with cultural and community facilities as well as commercial and retail development and is thus being used regularly instead of merely on game day.
“There are many examples around the world where stadiums have been built for particular events such as Olympics or World Cup, and they are a big of a ghost town after those events,” he said. “If it’s not active, in 10 years’ time, somebody is going to knock it down and build it again. You can imagine the amount of embodied energy thrown away by having a facility that is declared not fit for purpose and people deciding they need to replace it.
“You need something where you have designed it well and it will be useful and viable for many years.”
Glenn Scott, a principal and studio practice leader of the Sydney office at Hassell, says there is growing interest in achieving high sustainability ratings not just in sporting venues but in key entertainment, cultural and other iconic venues. The remake of Darling Harbour, for which Hassell performed the design work together with international design practice Populous, for example, is shooting for LEED Gold.
Scott says LEED is often the preferred rating tool for iconic venues which cater for international audiences, as opposed to more localised rating tools, due to LEED's level of recognition within the international community.
In terms of specific design considerations, both King and Scott say entertainment venues present a number of opportunities. With large amounts of roof space and lots of grass and open space to irrigate, there is no reason why rainwater capture systems should not be in place, they say. As is the case with the Levi’s Stadium, there are enormous opportunities to capture energy via solar panels which can then feed back into the grid, they add.
The spikes in energy demand on game day can also be accommodated with some forethought. In the Singapore example, what would otherwise have created a shock to the grid in use resulting from a bulk cooling arrangement for every seat is instead catered for by an arrangement whereby power is taken from the grid over a longer period of time to cool large tanks of refrigerant material and cool air is subsequently drawn from the tanks when needed.
In terms of how to go further, Scott says one challenge involves getting buy-in from clients. He says sustainability is often the first area where compromises are made when projects run into timeframe or budget constraints, and urges governments to specify minimum environment-related goals during the bidding process.
“I think governments should be taking minimum environmental targets when they go into these bids,” he said. “The industry can do it, designers here have the knowledge of how to do it. It’s just that it costs money to achieve those targets.
“I think the government should be willing to accept that extra capital cost. They will recoup that (though sustainability measures) because they reduce the effect of the stadium on the environment.”