they tried this on myth busters and it was totally busted. They tried to catch a ship on fire made of tar, wax, wood and stuff they used back in the old day and the diameter myth busters used was like 20' and it was massive. it did emit some heat but not nearly enough to light anything on fire, not even close. Mabe it would work on a closer object but i wouldnt keep your hopes up.
haha that reminds me of a simpsons episode where bart said to cheif wiggum "hootie and the blowfish?" looking at a tape used for recording their hidden mic and wiggum'* reply was "its cheaper than blank tape"