A single gallon of kerosene costs around $2.25. For a heater that works on 23,000 BTU, for example, you need around 2 gallons to heat up for 8 to 9 hours. That’s enough to warm up a house during a dead winter. Assuming you turn it on 9 hours a day, 30 days a month for 3 months, you’ll need around 170-180 gallons. That costs about $385 to $400.