What type of heating can wood be compared to coal? Today, only one.
Coal can be handfired stove, stoker stove, central heat and DHW, and all are practical in use (but can't touch oil/gas for convenience). Wood can only stretch in practicality as a secondary, handfired heat source and is the least convenient to use.
If you're just augmenting your heat and doing weekend fires, wood is ok. It's also ok for the corners of the coal burning season. I like the idea of averaging down the carbon emission of coal with wood, when I can.
But, wood doesn't stoke (pellets! great idea, not there yet), and central wood heat hasn't been sorted out. Outside wood boilers try, but are a mess:
This link is broken, either the page no longer exists or there is some other issue like a typo.
(12-15 cords per season!)
Gasificaton works great if you are a rich man, love to tinker, and have no problem setting up a 600-1000 heat storage tank in your basement (do what?). Here's some good details on an interesting project:
http://www.hearth.com/econtent/index.ph ... read/6929/
The best way to use wood for central is a finnish-type masonry heater (tulikivi), but they cost $20-30k and you need to design your home around it.
and you still have to stoke each load...
A top-of-the-line central coal unit (AHS or EFM) is about a 1/2 the *installed* cost of the Tarm and has been sorted out since the 1930's. You can go on long vacation with the savings and still have a warm house when you get back.
A stoker stove can last 3-4 days without loading and many get a full day on their hand fireds.
I have friends that live in a converted summer cottage year-round. They heat solely by their VC wood burner. Their yard looks like a wood lot for a tree service, filled with 'free' wood and a nice, (not very free) 27 ton splitter. Half the time their home is 'very cool' and they argue over who is going to go home to fire the stove, and when. I've tried to explain using coal to them, but they give me a curious cocked-head look my labrador gives me, and they laugh, as if I was replacing my car with a horse. I've given up and they have too, after 4 years they're remodelling and putting in central gas.
So, burning wood is more constraining; it takes a lot more time and effort - even if the costs of 'free' aren't acknowledged. That makes it a 'lifestyle' choice. Which is fine; it's not a bad one.