Posted: 31/08/2012 at 09:23
As an retired fire underwriter for one of the large Insurance companies, I am fascinated by incidents like this. I also use peat compost and have a plastic pollytunnel. To have a fire you basically need 3 things – fuel, oxygen and either a heat source at or above the fuels flash point or in respect of spontaneous combustion - a temperature at or above it's auto ignition point. The flash point of peat is 225 degrees C or 437 F and the auto ignition point is 260 degrees C or 500 F. The hottest temperature I have recorded in my pollytunnel this year is 45 degrees C or 113 F. Unfortunately, like UFO mysteries, you will probably never know what really happened.