Fuel-Powered Thermacell Mosquito Repellent devices repel mosquitoes by creating a 15-foot mosquito protection zone. Thermacell’s zone repellent technology eliminates the need for messy lotions or sprays, stopping mosquitoes before they can bother or bite you. Powered by a fuel cartridge that lasts up to 12 hours and repellent mats that last up to 4 hours each – Thermacell provides mosquito protection from your backyard to the backcountry with no electricity needed.