A fuel tank for storing an alternate fuel and providing the fuel to an internal combustion engine includes: an inner shell with an internal cavity designed to store fuel; an outer shell configured and positioned relative to the inner shell such that an interstitial volume is created between the inner and outer shells; and a heating unit positioned in the interstitial volume. In some embodiments, the interstitial volume is filled with air; in other embodiments, the interstitial volume is filled with a thermally insulative material.