Storing Coal for Emergency Heating?

In addition to my wood stove and woodpile, I keep a small stockpile of coal for emergency heating. I'm contemplating getting a bit more and finishing restoration of a couple of wood/coal stoves that were given to me.

Advantages:
- cheap like dirt
- slow, even, long-lasting heat
- cooler flue temperature; reduced fire hazard
- can be stored indefinitely
- very compact
- no explosion hazard in storage

Drawbacks:
- burns best in a stove designed for coal
- not suitable for wood stoves without some modifications
- small risk of spontaneous combustion
- some people find the smell objectionable

Has anybody else used or considered coal as an emergency heat source? How do you plan to use it?

Cheers,
Doug

Just wondering, why is it not suited for wood stoves?

I have a wood stove in the garage and I go through a lot of wood, never considered coal because I have a friend that owns a lumber yard and I get all the wood scraps he generates for free. Nothing like free heat. The garage has run on free heat (wood) for 25+-years.

I have an open coal fire in my living room. It's not just for emergencies - I light it most evenings and it is burning now. I probably should burn wood instead, but I've not found a good local supply and coal is cheap and easy.

As I understand it, coal burns very differently than wood. It requires an enormous draft, much more than a wood fire. A modern, efficient wood stove would be unlikely to provide enough air unless you kept the door cracked open.

Every coal stove I've seen, ancient or modern, holds the coal on a massively heavy grate so the draft can swirl all around it and the ash can fall away.

Coal also creates a very intense spot of heat as it burns. (Think blacksmithing: coal + draft = nearly molten steel.) Modern wood stoves would be vulnerable to damage since neither the brick nor the metal below could take that intense heat.

I wouldn't consider using coal in a wood stove unless I added a couple extra layers of brick below and a heavy steel plate for the coals to sit on. I've been thinking about welding together an insert out of 1/4 inch plate steel, with a grate above. But I'm still not sure about the draft issue.

Even then, it would have to be a genuine emergency, as it would instantly void any warranty on the stove.

P.S. BobS, Congrats on your endless wood source. Nice. Free heat warms you from the inside as well as the outside.

Brangdon, how is your coal-burning fireplace set up? And how do you get it going? I have this image of a massive stone Victorian fireplace right out of Dickens. Probably all wrong. Details, please.

BTW, that reminds me of another advantage for coal: it doesn't spit out sparks like wood does.

How does the low flue tempture affect the draft. I would think that if your flue tempture is lower you would need a larger flue to get the same draw. Most of the coal fired systems I have seen here have had what seemed to be a large flue or a forced air in take.

What kind of coal would you use ? The "soft" coal we have in western PA has a high sulfer content and makes yellow smoke with a rotten egg smell. Not plesent if you live in a valley.


Ward

Good point about flue temperature. No doubt it affects the draft. Based on what I've seen in antique coal stoves, they didn't necessarily use a larger flue; rather, they used a much longer one. The long flue would hang just below the ceiling of a building (think about a one-room schoolhouse or whatever) and radiate heat all the way along.

The longer flue has the same effect: it creates a vigorous draft, even when the fuel source is getting low.

The other draft factor is "over-fire air." Many coal stoves had mechanical thermostats that would admit air above the fire to maintain the temperature output.

And sometimes, as you have noted, a forced-draft fan was used on the intake. That was a late innovation. (However, in modern times, if I have electricity I won't be pulling out the coal stove.)

BTW: The coal we have here (Alberta, Canada) is very low in sulfur. Unlike our oil - go figure. Personally, I don't mind the smell, but the first ten years of my life were in a coal-heated house. So for me it brings back pleasant memories. But as they say, YMMV.

A lot of the draft depends on the chimney geometry. The house I grew up in has a wood fireplace w/ insert that can be lit with little kindling and several sheets of newspaper. No kindling (1/4 or 1/2 logs) and more newspaper was doable. You could hear the draft once it got started.

edit:
With this set-up coal might be possible. It would need some testing for draft and burn time. A full load of wood would last about 8 hrs w/ coals left to start the next batch.

Interestingly - I've been told that coal can indeed spoil! I know a lot of folks who use coal for their large scale model trains (Look up live steam trains - I'm building one)

It seems with 'soft' coal (bituminious) there are volates that are fiven off once you mine the coal/the coal gets repeatedly wet. I understand that lignite is worse, and that the problem does NOT happen with Anthracite

That said, it supposidly only happens VERY slowly, and mostly to the top few inches of your pile - and to the surface of each lump.

According to the folks I talk to the answer is to store the coal in fairly large size lumps (say, 'lump' size), and breack it down to the 'nut', 'pea' or 'rice' size you need as you need it - and to either cover your pile with a tarp, or actually bury it!

Supposidly only a real issue for multi year - say decade storage

BTW I've lumped (Pun is intended) coal into 2 broad classes above. Lignite, Bituminious, and Anthracite (from softest to hardest). There are lots and LOTS of subgrades. When you are looking for peak performance - say you are running a power plant or steel Mill - or, on the opposite side of the size scale - the guys who run the model trains, you design your grate, flue and other parts of the system around a particular coal, and try not to switch

The Live Steam guys swear by Welch Steam Coal - but it's VERY hard to get and expensive (hey - you have to bring it in from Wales), and they USED to love Pocohantas #7 coal - but I understand #7 mine is shut, and the closest you can get is #14 (yes, different mines have different coals - so do different seams from the same mine)

This topic brought back a lot of memories from my youth when we heated our home with a couple of fireplaces and a laundry heater! For the uninitiated, a full coal scuttle is heavy when you are six and the coal pile is 50 feet from the house. It's gonna be one heck of an emergency before I want to do any heating with coal!

Anyway.........a search under "heating with coal" on Google will yield a ton of information on the topic.

If you need heat in the winter, you will decide to do what is needed for it right away for your family. Or at least I would.


I think the point is to put in a fuel system that will allow you to have a reserve to allow you to have heat when needed.

I think propane (extra tanks and keeping them topped off) would be a very good way of having a buffer. But coal or wood could also work.

There is no wrong answers to this, but each heating option has to be thought out and you have to come up with a workable system before the disruption.

I like propane, but without electricity a propane fired furnace will not work. You would need to have a few of those wall heaters (the vent less kind) that work without electricity.

Coal & wood also work without electricity.

Interesting comments. Coal, as you point out, ranges from "packed peat" to "pure carbon."

I don't know about "spoilage" exactly, but I can tell you that our local coal (sub-/semi- bituminous) will fracture into smaller and smaller "fines" if exposed to the weather. Pretty soon it's approaching dust in its consistency. This is mildly problematic for use as stove coal; I may need to mix it with sawdust and pack it in old tin cans in order to burn it.

Meanwhile, coal stored in a dry outbuilding is exactly as it came from the colliery. So your point about storage is quite valid.

I'd love to get a quarter ton of that Welsh Steam Coal to play with. Wonder how much it would cost to FedEx it here? (Kidding, I'm a kidder. ;-)

My fireplace is a hole in the living room wall, about 18" wide, with a grate at the bottom and a flue at the top. I'm afraid I use firelighters to light it - I put one on top of the unburnt residue of the previous fire, light it and pile fresh coal on top. I've tried using bundles of newspaper and wood kindling, which is what my parents use to do, but it's too much hassle and makes a lot of ash. Coal produces very little ash.

It's vaguely like the ones here, but not as posh.

We are certainly needing to look at alternate heating methods. In my neck of the woods Propane is now $3.07 a gallon. In this milder winter climate - a hundred gallons a month of LP is now $307 when it used to be about $100 just a couple of years ago. The local firewood guys know this and delivered firewood is very pricy too. And natural gas seems to be in toe with propane.

We continue to look at alternate heat sources - Now that our son is old enough to know better, we are returning to buring more wood in our fireplace insert (splitting our own wood, of course) and reducing other areas of propane use - like getting back to hanging our clothes out to dry. We have recently added PV Solar to our house with a battery back up. We expect little to no electric bills in the future and could effectively function off the grid should a legnthly outage occur. We are already on a well and septic, so we are pretty capable of maintaining the basics at our home despite the ever constant water/power issues that pop up in California (rolling black-outs, water restrictions, etc.).

Does forge coal work well for heating?

Ah, very sorry to stir up your childhood traumas. ;-)

Coal, for me, means the ability to bank a fire in a stove that will last for six or eight hours. On the coldest night of the year, with the grid down, that's worth its weight in gold.

As for Google, well, it's certainly useful; but an ounce of wisdom outweighs a ton of information any day.

Thanks for the description. I need to build something exactly like that as an insert for my wood stoves.

You must have a high grade of coal to light it so easily. Ours takes a lot of heat before it really gets going, and won't produce much heat unless there's a good draft all around.

Do your neighbours object to coal burning, or is it commonly used in your area?

It sounds like you're fairly self-sufficient already. It's a good feeling, isn't it? Contrary to popular belief, the world does not stop turning when the grid has a spasm. It keeps rolling on as it always has.

Coal isn't exactly "green," being a fossil fuel. But it can give you a stockpile of heating fuel to fall back on, perhaps as an insurance policy for one's efforts to be less reliant on the grid.

Around here, there's a lot of it very close to the surface. You can even dig out thin seams from rivers and creeks. It makes sense to be aware of readily available local fuel sources.

One of my neighbours has an outdoor coal-fired boiler that heats his house, garage, shop, etc. It seems to burn very cleanly -- no belching smoke or anything. All I get is an occasional whiff of coal in the wind, and that's probably when the burner is firing up. But we live in the country, and there's a little more tolerance for things like that. (Barking dogs, though, are apparently another matter.)

My understanding is that "forge coal" is a high grade of bituminous coal with a low sulfur content.

Based on that, it would have a fairly high carbon content. So I think it would be fine for heating.

But perhaps some of the members who work with steel could give a more learned opinion. Thoughts?

It should, in a properly designed stove - thing is, forge coal is usually very high quality (metalergic coal) - to allow the blacksmith to weld steel without imputities - typically expensive

I just happen to have 2 barrels of it sitting around. Brother in law moved away 10 years ago and his wife wouldn't let him bring it or his 2 forges.
It's just nice to know that it's there if I was desperate enough to start burning it. Now I just need to come up with a way TO burn it.

The firelighter burns for 5 or 10 minutes - it's a commercial product designed for the job so it ought to make it easier. It comes as a biggish brick which you are supposed to break into small tabs. I actually break it into double-tabs. A single tab isn't enough to get the fire going, and two work best if they are close together. I can't really remember how much success I had with the paper and kindling approach; it was a long time ago that I stopped using it.

The firelighters add a significant cost to each evening's fire, and I stockpile them much as I do the coal. The grate and chimney means there is a good draft.

It's not common. I'm not very social, so I don't really know what they think.

"Do your neighbours object to coal burning, or is it commonly used in your area?"

No, they burn coal too! However I used to live in a major city in the UK that was classed as a Smokeless Zone this meant no open fires unless you were burning a special (read expensive) low smoke coal-like fuel. These zones came about from the era when lots of people burnt coal in densely populated areas and smog became an issue.

However even regular coal will burn relatively clean once the fire is established, it is only when you feed the fire with fresh coal that the smoke levels rise again temporarily.

Interesting! I seem to recall that coal burning was banned in Victorian London when Parliament was in session, because the MPs didn't want to breathe in all that smog.

I have one of my small coal stoves mostly together and installed in a cabin. I think I'll try to fire it up this weekend. Might even try to post some pics.

Just a side note. Coal is graded by checking it for sulphur content, how much ash it produces and BTU output.

Low-sulphur, low-ash high BTU coal is more expensive since it burns hotter, burns more completely and puts out less raw material for the formation of acid rain.

If you go to buy some coal, be sure to ask for the content ratings.

what about storing bags of charcoal for an emergency?

You mean charcoal briquettes? The BBQ type?

Well, if you kept them dry, they would keep just about indefinitely. And they would provide a slow, even heat when burned in a wood stove. You could also cook with them of course.

In mild climates, charcoal in a fireplace would break the chill and be cheery to boot. But it would take quite a large volume to keep a house warm in a three-day blizzard.

Unless you were able to buy charcoal in bulk, I think the cost would be a killer.

understandable with the cost, was just thinking that it could be a viable option

I think you're right: it is a viable option. It's hardwood, after all, and puts out a lot of heat. The only question, from a planning perspective, is whether it gives the most bang for the buck. But in an emergency I'd be very glad to have it. And of course it's easier to justify because it's dual purpose (always be prepared for Steak).

Anybody know an inexpensive, bulk source for charcoal?

Dougwalkabout is right about keeping the charcoal dry. The big danger is that if it gets damp/wet, it has been known to spontaneously combust. Don't think that is a good thing. Aside from the cost, an unintended fire could be a killer too.

Coal is safer.

I didn't know charcoal could spontaneously combust. Mostly I was thinking it would break down if exposed to too much moisture and end up useless as fuel.

Coal may be safer, but it is vulnerable to spontaneous combustion as well. I did some tech writing for an 800MW generating station some years ago. They had finely-ground piles of some 100,000 tons in reserve, of the bituminous variety, and were always monitoring for trouble.

I have small amounts stored in buildings, mostly in 5-gallon plastic pails. But the larger volumes are in 55 gallon steel drums, stored outside with tight-fitting lids. (Apparently, by accident, I did the right thing. Go figure.)

Anyway, here's a link about the spontaneous combustion of coal, which seems correct to me. Bonus: anecdote from the coal-fired Titanic at the end, which I hadn't heard before. http://www.saftek.net/worksafe/bull94.txt

wow; we both learned something. Interesting info. thanks.