Gas forced air....costs very little....highest bill so far about $140 and that includes a 50 gallon water heater....not bad for a 2700sq foot house+ heated garage and temps rarely above 25! (Its NINE right now)

We have a fireplace but it needs internal repairs that we don't want to deal with/pay for right now, I'll fix it in the summer and use it next year. I set the house to a cool 66 degrees and add extra heat to the room we are in with an electric heater.

Helps to have a 92+ % efficiency furnace....I also re-capture heat from the dryer and such. (electric not gas!)

Once I replace all of our windows it will likely save us a bundle on our bills.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)