Frost Protection - UTL Repository

In the USA, growers were given a few years to find a less polluting method of
frost protection. Eventually, the “return stack” heater, which recirculates smoke
and vapour, was developed and used for some time (Leonard, 1951). Today,
return stack heaters and clean-burning propane-fuel heaters are legal in many
locations; however, before using any type of heater, local regulations should be
checked. However, the perception of increased fuel costs and pollution issues
during the mid-1900s has led to the demise of most heaters for frost protection.
During the 1950s, wind machines began to replace heaters as the preferred
method of frost protection. They were more expensive to purchase, but the
labour and operational costs were lower. By the 1970s, the use of heaters for frost
protection was almost non-existent in California. Small fires and solid-fuel
heaters are still used in some parts of the world. However, it is likely that the use
of all but clean burning heaters will stop eventually.
[
]
F R O S T P R O T E C T I O N : F U N D A M E N T A L S , P R A C T I C E A N D E C O N O M I C S
16