Refrigeration firm Realcold recently installed a state-of-the-art refrigeration system at the new Metricon Stadium on the Gold Coast.
The recently completed Metricon Stadium in Queensland is one of the most environmentally advanced facilities of its kind in the world.
Built on the site of the previous Carrara Stadium at a cost of $144 million, the new home of the Gold Coast Suns AFL club can generate up to 275mWh of energy a year from photovoltaic panels built into the roof canopy.
Alongside its low energy lighting and rainwater harvesting system, the facility is equipped with a state-of-the-art refrigeration system designed to deliver substantial savings in energy costs.
Catering for refrigeration requirements at major sporting venues can be challenging, due to the enormous swings in load.
With capacity crowds on match days, demand on the refrigeration system rockets as the bars and food catering facilities across the stadium swing into action to serve the needs of thousands of spectators, all requiring service within the space of a few hours.
This is followed by the periods of very low or no demand between events, when cold stores and drinks coolers are either emptied or kept on maintenance duties until the next big day.
Vaughn Strydom, who headed up the refrigeration design and build project for Realcold (finalist in the AIRAH industry awards 2012) says energy efficiency was a key design requirement.
“With efficiency as a key design requirement, self-contained integral refrigerators could not be used due to the additional load these would have placed on the air conditioning system,” he says.
“Fractional horsepower machines were not practical due to the long pipe runs involved in this kind of application, and the sheer number of locations required.
“With the swings in demand, it would also have meant that the system would either be under capacity or short-cycling.”
The solution, installed and commissioned by Coldwell Refrigeration, is a system based on high performance condensing units, with refrigeration loads distributed as evenly as possible across each of the stadium’s service areas.
The system consists of a total of 14 condensing units, based on high efficiency semi-hermetic reciprocating compressors from Italian manufacturer Frascold, and running on R404A.
To meet energy targets, the majority of compressors are equipped with integral variable speed drives (VSDs). It is believed to be the first installation in Australia to use Frascold’s recently launched compressors with built-in variable speed drive.
The condensing units serve some 72 different loads across the stadium, including cold rooms, freezer rooms, under-bar refrigerated counters, upright glass door display cabinets, blast chillers and blast freezers.
The eight condensing units equipped with VSDs cool all perishable food and support in-bar bottle cooling equipment. The six compressor-only systems are used on match days to augment beverage cooling.
The compressors selected are a combination of Frascold two-cylinder D models and four-cylinder Q models, with capacities of between two and 5hp.
The total cooling capacity of the system is 140kW.
As a result of careful overall system design and the use of inverter-driven Frascold units, the refrigeration system is expected to use up to 40 per cent less energy than a conventional system, Strydom says.
“The key is to balance the cooling load across the system as far as possible, to ensure that the equipment operates as efficiently as possible,” he says. “The use of inverters ensures that output can be matched as closely as possible to the varying load,
to cater for the peaks and troughs that occur in the use of the stadium.”
Mark Sisson, general manager of Realcold in Australia, says the system represents
big cost savings. “It’s a superb system, and matches the strong environmental credentials of the outstanding facility as a whole,” Sisson says.
“Over time, it will deliver a huge reduction in energy consumption that will translate into serious savings for the operator.
“As energy costs continue to rise, and demand for environmentally responsible cooling grows, we believe energy-saving technologies such as this will grow significantly in popularity.
“Pay-back times are reducing as power costs increase. It has proven to be a worthwhile investment that pays for itself very quickly.”
The Metricon Stadium is set to play an important role on the international sporting stage in coming years, following Australia’s successful bid to host 2018 Commonwealth Games.