Brewing generally consists of: Adding your grain to water to form the mash. Cooking the mash to extract the sugars et al. Separating out the mash into the wort

Brewing generally consists of: Adding your grain to water to form the mash. Cooking the mash to extract the sugars et al. Separating out the mash into the wort and the solids. Boiling the wort. Cooling the wort, then pitching in yeast. Then storing for a while while it ferments. Heating the wort and mash could be done electrically, but generally (especially at brewery scale) is combustion.