Many parts of North countries tend to have harsh winters. In addition to that in many villages tend to have bad heating systems which would make living in this area hard for the people. You have to design an efficient heating system that will be sustainable for years and will be affordable for the people considering that electricity tend to be more expensive in this places.
Efficiency- a system that would produce heat the most efficient and provide explanation/evidence
Affordability- total price of the system should be low enough to be done by the government for each village or be purchased by the village instead
Sustainability - explain how this design will be sustainable by explaining
