I installed a mini split heat pump last year (heat and air conditioning), to supplement my oil fired furnace. It was the best, most economical decision I could have made. The new generation heat pumps are less expensive and more efficient (SEER rating), compared to the older versions some folks remember from even a few years back.

Overall, I more than saved the cost of the unit and installartion (which was not very complex), versus using total oil, in one season. And, unlike the older versions, it produced heat down to -21 celcius (as cold as it got last year, where I live).