Pushing a crowbar into a hay bale to test its temperature could soon be replaced with a more effective method of determining whether or not fodder is at risk of spontaneous combustion.
Moisture in the bales, sugar levels in the hay, aeration and temperature are all factors that contribute to fires, but how they interact to cause a spontaneous combustion is not properly understood.
Researchers from Charles Sturt University have started equipping bales near Wagga Wagga, in southern New South Wales, with monitoring equipment to understand how blazes happen and how farmers can reduce the risk.
Lead researcher John Broster said the hay industry, from export hay right down to drought reserves, was worth about $2.5 billion.
"So if 1 per cent of that is lost to spontaneous combustion, that's $25 million, plus the impact on the farmer and the property," Dr Broster said.
"It can be very devastating — they lose their crop, they lose income, they lose infrastructure.
Alerting farmers to risk
Dr Broster and his team attached sensors to a stack and burnt it to mimic an arson attack.
They gathered data on how the fire spread so they could compare it to spontaneous combustion in other bales they were monitoring.
"The temperature is really a symptom of what is going on with the moisture and its interaction with the sugars," Dr Broster said.
He said he also wanted to test where to best place the sensors that measured temperature inside the bale.
The researchers and their partners said they hoped to roll out smaller sensors to farmers that would monitor temperature and report back to the farmers' mobile phones.
"It will send alerts to the farmer when their stack reaches a certain temperature," Dr Broster said.
"If we can understand that and test it under Australian conditions and get farmers to adopt it, that will mean they'll have more accurate warning of the potential for a stack to spontaneously combust, and they'll be able to manage it."
Technology company Myriota will connect the sensors to their satellite system so alerts can be sent despite poor mobile coverage in rural Australia.
Myriota representative Paul Sheridan said haystack fires happened in remote locations where there was normally no mobile phone connectivity.
The sensor technology already exists, so once it is connected to the satellite system, it is hoped farmers around Australia can place sensors into their bales to monitor whole stacks and warehouses for risk of spontaneous combustion.
