Cast iron stove sits in the kitchen center. Heats the whole house. Cook on it. Bake in it. Coil inside heats water.
Economics
Firewood — free (own forest). Gathering — family work in autumn. 5-7 cords for winter. American gas bill: $1,200/year. Amish: $0.
Cooking
Temperature on a wood stove isn't precise. 'Hot' — hand tolerates 2 seconds (220°C). 'Medium' — 5 seconds (180°C). 'Low' — 10 seconds (150°C). Amish cooks cook by hand, not thermometer. And their pies are better.