Which method produces light with minimal heat generation?

The method that produces light with minimal heat generation is electroluminescence. This process involves the emission of light from a material when an electric current passes through it or when it is subjected to a strong electric field. Common examples include light-emitting diodes (LEDs), which are highly efficient and convert a significant portion of the electrical energy into light rather than heat.

In contrast, fusion and combustion both involve reactions that generate substantial amounts of heat energy along with light. Fusion, as seen in stars, releases energy through the combining of atomic nuclei, while combustion involves the chemical reaction of a fuel with oxygen, producing heat, light, and exhaust gases. Conduction is a mode of heat transfer that occurs via direct contact, not a method for producing light, thus making it unrelated to the question.