Cool And Go

17 September 2008

Large outdoor events such as the Farnborough International Airshow, require cool conditions in the temporary buildings built for the massive trade show to ensure that the aerospace industry can do big
business deals in comfort. Jane Fenwick reports

CELEBRATING THE FIRST POWERED FLIGHT in the UK 100 years ago this year and its 60th birthday, the
Farnborough Air Show in July was, as always, vital showcase for the UK and global aerospace industry. The airfield at Farnborough is transformed every two years to host the latest in aircraft technology from the private jet for the super rich to warplanes bristling with deadly payloads.

The glamorous part of the four-day show is the daily display that roars over the airfield offering an awe-inspiring display of the latest in military technology, or nostalgia for planes of the past such as the newly restored Vulcan bomber making its first appearance at this year’s show.

But the real business of the event takes place in the exhibition area beside the runway that is claimed to be the world’s largest temporary exhibition facility for 1500 exhibitors from 35 countries. The build-up for the trade show started four months before the event in July. Some 3,600 tonnes of temporary structures are
transported to the show site and 90,000 sq. m of structures are erected to provide tailor-made floor space that would accommodate the Royal Albert Hall no fewer than 30 times.

The trade show attracts visitors from all over the world ready to make deals for parts or planes worth for £ms every day. At the last Farnborough Air Show two years ago in 2006, trade week accumulated US$42bn worth of orders.

For the trade show exhibitors this is a critical business event representing a significant investment in their future business and which required the same environmental conditions as if business was being conducted in a permanent air-conditioned building.

Supplying cooling to these huge ‘tents’, the meeting rooms, the restaurants and the vast majority of the corporate entertainment area is Carrier Rental Systems. At the 2008 event, some 30 chillers and hundreds of air handling units were installed to provide a target temperature of 18C whatever the temperature outside. The five vast exhibition halls together comprise the largest outdoor temporary cooling installation in Europe. One hall - Hall 4 – is, at 20,000 sq m, and is among the largest single cooled temporary spaces in Europe.

Carrier provided a record-breaking 14.5 MW of temporary cooling, more than ever before. Its team of six engineers ensured the systems are maintained and any problems that were handled quickly day or night throughout the duration of the event. The Carrier installation teams are on site for two months before the event, and most of the equipment was removed and sent to new hires within three weeks of the Show closing.

As the preferred supplier for the Farnborough Air Show through to 2012, Carrier secured more than three-quarters of all the air-conditioning equipment supply, and provided all the temporary power and power management for its own installations and some others on the site.

The installation is based on brand-new Carrier Aquaforce high efficiency design chillers with micro- channel heat exchange technology, supplied direct from Carrier’s manufacturing plant in France. According to Carrier’s Marc White, “These chillers have the advantage of independent operation of multiple circuits, ideal
for temporary installation since they offer flexibitiy and security of operation in the rare event of component failure.”

Sited outside and adjacent to the both ends of the exhibition halls, the chillers and related generators gently throb behind temporary but robust screens as the cooled air is pumped into the halls through perforated fabric ducting that dispenses the cooled air at roof level. New this year is a new return air system that takes a
percentage of the already partially cooled air back into the handling units and re-circulating it. This has improved overall efficiency and reduced the energy used.

The system has evolved since the first Show in 2000, with improvements and innovations being introduced. Many are small innovations such as simple fixings that simplify installation and help reduce time on site for installation engineers. Most of the equipment is re-usable and in constant use within the chiller rental
business from the kilometres of perforated fabric ducting to the safety fencing that surrounds the chillers and generators outside the tents.

The numerous air handling units of various sizes have energy saving controls built in. the large air handlers supply over 60,000 cu m of air per hour and are inverter controlled. The smaller units are supplied with chilled water from the chillers via a ring main design and can be manually controlled by the occupiers of the
spaces to meet their precise individual needs.

Chilled Ascot
Earlier in the year at Royal Ascot, Carrier Rental Systems, provided a megawatt of cooling to one of the massive grandstands which was a giant tent. Keeping the punters cool all day long Carrier Rental Systems installed six chillers. The three-deck, L-shaped temporary grandstand was constructed within just three weeks. Carrier was involved from the outset, ensuring that pipework, cabling and electrical power is appropriately integrated. Quick connection designs are used to assist all contractors’ requirements.

All of the power for the building, including that needed for the kitchens and the hospitality services such as plasma televisions and lighting for the daily fashion show events, was also provided by Carrier Rental Systems from two 500 kVA generators.

The building, which will be retained for a month of special summer events at Ascot, has a glazed frontage to all three stories. When determining the required cooling capacity, Carrier Rental Systems’ specification team had to take into account the thermal values of the glazing, the number of guests, and the programme of activities in the building. The positioning of the almost 70 smart interior air handling units required is crucial. The selection of indoor units brings big advantages as they can use 100 per cent recycled air which cuts the power requirement and the chiller capacity demand by over 50 per cent This, in turn has reduced the hire charges and the running costs significantly if compared to alternative solutions in the marketplace. The fact that the system is heat pump based also enables heating to be provided to the empty spaces in the early morning and then be switched to cooling as ambient and internal temperatures rise.

Each of the six chillers has four compressors and two separate circuits which while providing automatic contingency cover in the case of failure also enable the equipment to take advantage of low starting currents and staged loading to more accurately meeting the capacity requirement at any point in time. The chillers are
microprocessor controlled and operate at impressively low sound levels sited as they are in a plant compound away from the building. They give only 63 dBA at 10 metres.

Large scale public events such as the Farnbourough Air Show and Royal Ascot have more than proven the technology and logistics of providing comfort conditions for business and pleasure. With the London Olympics just around the corner in 2012, this could well be a solution that the organisers turn to for cooling the athletes and visitors in many of the locations built for the Games and not intended as part of the legacy facilities.