Home heating economy can vary widely with location. Comparing fuel prices gets frustrating because of how rapidly they change. A home heating system is a long term investment and you need to look at fuel prices over the last decade or so before making a choice. Having a second source of heat can save money in the long run by allowing you to use the cheapest fuel at any point in time.
When I built my house in the late 1970's, coal was the cheapest per BTU since I'm located in the Anthracite coal region of PA. I burned it for 30 years with an oil furnace as backup. Over the years, the price of coal creped up. Last year, it got to the point where the savings over oil weren't worth the effort required to maintain the stove and I switched to oil.
Earlier this year, the 45 year old oil burner needed replacement and I again had to decide on which fuel to choose. I considered propane since it burns cleaner with less maintenance. Propane and fuel oil are very close in price per BTU right now, but I ultimately decided to stick with oil, since I also use it to fuel my tractors.
Up until recently, electricity rates here have been quite low. My AC system also needed replacement so I installed a ductless unit that also provides heat. For a time, the efficient heat pump system actually made electricity the cheapest source of heat. That all came to an abrupt end though since the electric rates have almost doubled in the last 6 months.
So now, it's back to oil again with electric and the old coal stove as backup.
This is just my story, but an example of how things change over time. YMMV.