Should I heat my barn with gas or electricity?

October 24, 2010 12:08 PM

We have an old barn in our backyard that we are currently restoring. It will be fully insulated when finished (though we're recycling old windows that are probably 100 years old, which are single pane, so it won't be optimally efficient.) I am trying to decide if we should heat it with gas or electricity. Because the barn has never been heated before, and we're changing it anyway, I'm having a hard time estimating costs. (See extended explanation for details.)

The barn is already wired for electricity (and we have more than enough capacity), so adding electric heat will have a trivial cost. Installing gas heat is likely to run about $4,000 all-in. The barn will be used at least 5 days out of every week, ten hours a day, so it will need to be well heated. We live in the greater Seattle area and pay about $0.098 per KWH for electricity, and about $1.058 per Therm for gas. Our home heating bills tend to drop to near-zero for about three months, and are significant for nine months. The barn is 20' by 22' and is unusually tall (about a story and a half.) So it's a big, open space on the inside.

So, all that said, I'm trying to very roughly guess in how many years I'll "break even" by installing gas heat instead of electric. Anyone have any ideas?

posted by djedery to Home & Garden (8 answers total)

I know nothing about heating. This is just my own experience.

If it is at all possible I really recommend radiant heat floors. Especially for a place with high ceilings. We have one of the only homes in our area with vaulted ceilings and it would be impossible to heat inexpensively without our radiant heat floors. Ours is done with a very old boiler that runs on gas, but I believe radiant heat can be done with electricity too.
posted by TooFewShoes at 12:35 PM on October 24, 2010

I dunno about KWH / Therm conversions, but we once rented a house in Maine that had electric heat and the cost was through the roof The place was insulated too. Unless you plan on super insulating the Barn, I'd go with gas, especially considering the volume of the space to be heated. We have a gas wood stove ( Vermont Castings...cost 3K install $500) that heats a fairly large uninsulated cabin very well...and it works (except for the fan) when the power goes out.
posted by lobstah at 2:07 PM on October 24, 2010

I'm trying to figure out why it should cost near $4k to heat what is, essentially, a tall two car garage. We converted our two car garage into a work studio for my wife. It is fully insulated, but on a concrete slab and is in Eastern Tennessee. If the expense is in extending the gas line out to the barn, consider installing a propane tank and a simple propane space heater. You might be looking at $1500 to $2000 at the most. Next, what would the cost of the electric heater system be? You are really only looking at the marginal cost difference between these two systems, not the total cost of the gas system when you are looking at payback.

Lastly, consider installing ceiling fans in the open ares. Driving the hot air back down to the floor level really cuts the cost of heating.
posted by Old Geezer at 3:05 PM on October 24, 2010

My experience with electric heat is that it's very, very expensive unless it's underfloor electric heat in which case it's only very expensive. A gas boiler that runs radiant underfloor heat would be my suggestion too. You don't have to pour concrete over the newer PEX systems anymore so they are much cheaper and easier to repair. Make sure it's a frost proof system, even though you're in Seattle.
posted by fshgrl at 3:14 PM on October 24, 2010

Response by poster: Old Geezer: RE. the high cost -- it is because we would need to extend a gas line out to the barn, yes. I will investigate the cost / practicality of a propane tank -- thank you for the suggestion.
posted by djedery at 4:55 PM on October 24, 2010

It really depends on your location and the price of the fuels. A good gas heater is 85% efficient. One therm is 100,000 btu. One kilowatt hour of electricity is equivalent to 3412 btu when used for resistive heat, so you're looking at about 24 kilowatt-hours of electricity being equivalent to one therm of gas.

Or in the more usual billing formats, 240kWh is equivalent to about 1 dekatherm or 1mcf of natural gas.

If you get a heat pump system rather than resistive heat, you'll use much less electricity than you would with purely resistive heat.

Without a heat pump, if the prices you quoted are all in and include any fuel charges or transport/distribution charges, gas heat will cost about half what electric heat does, presuming you get a furnace that is at least 85% efficient. If you get a heat pump with a coefficient of performance of at least 2, the running costs should be similar. The other advantage there is that you get air conditioning capability thrown in for free.
posted by wierdo at 4:59 PM on October 24, 2010 [1 favorite]

Propane is really expensive... And electric heat is usually off-the-charts high. When you say gas, do you mean natural gas, off the street? That's going to be your cheapest option in the long-run. Rinnai makes an incredibly efficient gas heater. I lived in upstate Vermont for years and heated a two floor 1100 sqft apartment on no more than 60 bucks a month. It was often -20 degrees in the dead of winter.

I'd run from electric and propane.
posted by Glendale at 7:01 PM on October 24, 2010

Whichever heat option that you choose, consider getting wood storms with internal/swappable storm windows and screens to exponentially improve the heat retention within the barn. You can save some money buy getting the frame kits, ordering the glass/screen inserts locally, and assembling them yourself. We love them and they have made a huge difference to our old house. Especially since wood insulates better than metal storm frames and looks/holds up longer than vinyl.
posted by jeanmari at 7:15 PM on October 24, 2010