We had guests in december who stayed for one month and used more electricity in one month than we would pay in one year, nearly 2000 kw in one month, I did not know that much could be used. The bill was huge and we have complained to airbnb and the guests. We do expect guests to be thoughtful about how much they use, we could feel the heat coming through the walls as we are next door. Our bill was a quarter of theirs and we kept warm. Yes you are within your rights to ask guests to conserve and turn heaters off. from now on we will be charging for over used electricity or claim from deposit.