Tim Henman Slazenger tennis ball

Tim Henman with this year’s official Slazenger tennis ball – a slave to refrigeration

The Wimbledon Championship, which reaches a climax this weekend, is a huge undertaking with its success or failure reliant upon, not the quality of the games or the clemency of the weather, but good old refrigeration.

From the players cold court-side drinks to the nine chillers required to air condition the covered Centre Court, refrigeration is making its unheralded contribution to this hugely popular annual sporting event.

Whether it’s conserving the 7,000 litres of cream needed to adorn the traditional Wimbledon strawberries or chilling the 25,000 bottles of champagne, refrigeration is essential. On top of that there’s the cooling load that must be met for the 100,000 pints of draught beer and lager downed during the championship, not to mention the refrigeration demand to ensure that the 135,000 ice creams and 20,000 portions of frozen yoghurt don’t turn to slush. Then there’s the mountain of food to be kept chilled or frozen for the hundreds of thousands of lunches. And just what would the 200,000 glasses of Pimms be without ice?

So many areas of our lives rely on refrigeration and Wimbledon fortnight is just a high profile example, but it’s not just behind the scenes where refrigeration is essential. On court, the tennis balls also have to be kept at the correct temperature for play.

Official supplier Slazenger delivers around 54,000 balls to the Wimbledon Championship each year. About 20,000 of these are used for qualifying and practice but all are kept at 20ºC to keep them in perfect condition and with the right amount of bounce.

Modern tennis balls are made of a hollow rubber core and covered in a premium woven cloth and then steamed to produce the familiar fluffy exterior. Pressurised air inside the rubber core is what gives the ball its bounce and, as every refrigeration engineer knows, temperature has a marked effect on pressure and, hence, the amount of bounce.

At one time the balls were kept in fridges, court-side . The New Yorker magazine from 1968 records that a “Lightfoot Automatic Electric Refrigerator” was used on Centre Court to ensure consistency of bounce in the ball. It also reports that head groundskeeper Robert Twynam also used the fridge to store his butter and milk until he bought his own refrigerator.

So, while the applause will be directed at the winners this weekend, it’s worth reflecting that they probably wouldn’t have achieved their success without refrigeration.