I gel most of my soaps, and rarely use an oven. Sometimes I pre-heat a mold in the oven, but even that can be done without the oven itself - you can, for example, warm up one of those rice-filled heating bag in the microwave and pop it into the mold while you work. But mostly I just put my filled molds into a styrofoam cooler and leave it to gel. The reaction releases heat...