Welcome to the New Year 2021!!! I'll share with you how I heat my house. I've been using wood and anything else that burns for three years now. One truckload of 8-9 stacked meters of firewood is enough for the winter. The house is about 80 square meters, built of one and a half sand-lime bricks, insulated with 5 cm EPS. I heat it from 6:00 PM until 11:00 PM, maintaining a temperature of about 18-19 degrees. By morning, it cools to 16-17 degrees, and I go to work. I come home at 5:30 PM and start all over again. I burn about 20 kg of wood per day. The system is gravity-fed. The radiators are cast iron, and there's plenty of water.