We have a heat pump. Supposed to be cheaper to heat than gas but also slower to heat. We rarely use it as you have to leave it on for 36-48 hours to get the heat up. We don't have a blanket though which would stop the overnight heat loss. But the getting in and out bit is hard when it's off season. Heard that solar can ruin your roof tiles and can get damaged by birds. Good luck with your decision.