MORE than 100 anti-frost wind machines will dot the Coonawarra landscape in a bid to mitigate vineyard frost damage following last year’s losses.
Wine giant Treasury Wines, owners of Wynns Coonawarra, have been granted approval to install New Zealand-designed Frostboss C49 and C59 fans.
According to Wattle Range Council’s development application listing for June and July, the world’s largest listed wine company will install close to 100 of the four blade fans and 12 five blade fans at its Limestone Coast vineyards.
The fans will be placed in a number of locations, including sections of the Riddoch Highway, John Riddoch Drive, Redman Avenue and Lynch Road.
Each machine comprises a tower 10 metres tall and 40cm in diameter, with a five metre fan driven by an engine at the base of the tower.
In a statement, a Treasury Wines spokesperson said the frost fans installation, reportedly valued between $4m and $5m, was a significant investment for the estate.
“Last year, a number of vineyard regions throughout the Limestone Coast, were impacted by a significant frost event,” the spokesperson said.
“Hence we are taking steps to mitigate against future frost risks, by installing frost fans throughout our vineyards.
“Frost fans are a common frost management mechanism, particularly in the Coonawarra region where water availability is limited via water allocation licenses, thereby making it less viable to utilise frost sprinklers, one of the other common frost management tools.”
The spokesperson said the company was “well advanced” with the installation of the fans.
Each tower will be erected on a concrete foundation measuring 4.8 square metres and with a depth of almost one metre.
According to the manufacturer’s website, the wind machines are turned on before a frost occurs – usually 0.5 to 1.5 degrees above freezing.
“Wind machines have become the central element in most frost protection strategies,” the Frost Boss website says.
“They use the warmer “inversion layer” air to protect a crop from frost damage.
“The wind machine fan is angled slightly to pull this inversion layer down to ground level to protect the crop from frost damage.”
During frost conditions, the ground temperature and the temperature of air adjacent to the ground reduces to a temperature lower than the temperature at a higher level.
When the blades rotate, large volumes of the warmer air are moved to ground level.
The fans are required to operated when the temperature reduces to below 0.5C to protect the crop, which generally occurs in the early morning hours on a limited number of occasions.
According to the Frost Fan website, a single frost fan will provide protection for about six to eight hectares, with multiple frost fan installations increasing the effective coverage of individual fans.
