During the coldest part of winter I often heat with coal instead of wood. To my way of thinking nothing keeps you as warm as coal. There are two main types of coal used in the United States for energy: bituminous coal and anthracite coal.
Bituminous coal is the most common form of coal. It is the type of coal that is use for electric power plants, but it is also used for home heating.
Bituminous coal is dull and dusty looking and is easily burned. It is considered to be a soft coal and burns sooty.Bituminous coal contains 10,500 to 14,500 BTUs per pound.
Anthracite coal is a denser, harder coal that is found in the US, but only in eastern Pennsylvania. Anthracite coal is about twice as expensive as bituminous coal and is almost always used for home heating and not for electricity generation. Anthracite coal is shiny and waxy looking and burns clean. Anthracite coal contains about 15,000 BTUs per pound.
The advantages of coal for home heating are many.
Coal can be safely stored for an indefinite period of time and it never goes bad.
Coal doesn’t rot or draw insects like wood. Coal does not need a pipeline, or any type of special tank or container like LP gas or fuel oil.
Depending upon your location, coal is often a more affordable home heating option when compared to either fuel oil or natural gas.
Best of all, coal is not produced by people who want to behead you or hate you. Coal is a 100% American energy resource. Coal is abundant in the United States and many coal mines are still small mom and pop operations. Coal makes jobs for Americans.
The last I knew, Pennsylvania has enough anthracite coal for home heating needs for about another 150 years or so – maybe longer.
A coal fire puts out more BTUs than most types of hardwoods. Osage wood is the only wood I can think of that will burn as hot as coal. Coal is readily available in many areas of the country and is most often sold in 40lb. bags or in bulk.
Now before you rush out and buy coal for your wood burning stove there’s a few things you need to know.
To safely and effectively burn coal you must use a multi-fuel stove or appliance. Coal fires burn too hot for most standard wood fuel boxes. Burning coal in a regular wood stove or furnace can result in an overheated stove, a burned out fuel box; a warped stove or a house fire.
Coal or multi-fuel stoves or furnaces have a way to bring air to the fire from underneath. Coal appliances are designed with a cast iron slotted grate and have some way to shake or tip the grate to clear out ashes and leftover coal clunkers. Coal must have free circulating air from beneath in order to burn properly. Any buildup of ashes under the grate will inhibit a coal fire.
How To Start & Maintain A Coal Fire
Coal fires unlike wood fires can be hard to start and need to be tended to differently.
I’m going to assume that if you’re interested in burning coal that you already know how to start a fire in a stove or in a furnace.
I’m also going to assume that you have a multi-fuel stove or appliance.
Along with a poker you’ll probably want a coal hod and a small shovel to manage an indoor coal fire. A coal hod is also called a coal scuttle or coal bucket. Coal hods frequently have a pitcher-shaped end for pouring coal on a fire. Coal hods are usually made of metal and have a handle for carrying small amounts of coal.
To start a coal fire, you’ll first need to have a good strong wood fire going.
Depending upon the type of coal you plan to burn you’ll need a bed of hot wood coals.
About 1”-2” of wood coals is a good place to start for bituminous coal.
With anthracite coal, about 2”-4” of hot wood coals is what it usually will take to get it started.
With both types of coal, the coal fire is started by adding just a small amount of coal on top of the wood coals.
Open the lower door or damper of the stove so that coal is being fed air from beneath. Wait about 5 minutes and add about twice as much coal as the first time.
After about 10 – 15 minutes add more coal and watch for the blue flame that is characteristic of coal-burning.
At this point you can close the bottom door or damper. Once there is a full bed of ignited coals on the grate an entire hod of coal can be added. The way that I add coal by the hod, is I open the bottom door, and then just throw or pour an entire hod of coal on the fire.
I wait to make sure that I see blue flames creeping up through the coal before I close the bottom door.
Many people who become frustrated with coal burning fail to appreciate the differences between the two types of coal.
With anthracite coal it’s important to neither rush the coal ignition nor to stir up or poke the fire like a wood fire. An anthracite fire needs to have the grate gently shaken or lifted slightly and moved every once in a while. If you disturb an anthracite coal mass by poking or stirring it, the fire will tend to go out and you’ll be left with unfired clunkers.
With a bituminous coal fire, the coal will tend to burn and lump together into a large solid mass. Bituminous coal fires need to be lightly poked and stirred up in order to burn completely.
The most important thing to understand about burning coal is that it doesn’t burn like wood.
Coal radiates and burns from the bottom to the top. The fire spreads upwards through the coal and one piece of coal will ignite another. When a coal fire is properly burning there is little flame. The coals just glow.
An entire hod of anthracite coal will keep my 1200 square foot house comfortably warm in -15F° weather for about 6 hours. In sub-zero weather I used just over 1 bag of anthracite coal a day.
I never burn bituminous coal in the upstairs living area of my house because of the soot. However I do burn bituminous coal in my basement stove to keep the plumbing from freezing in sub-zero weather.
Anthracite coal has a more complete combustion than bituminous coal. Anthracite coal leaves little ash and waste when compared to bituminous coal. Unlike hardwood ashes, I don’t spread coal ashes on my garden. Instead coal ashes are scattered in my driveway to melt ice and snow.
Some people prefer to start coal fires with outdoor charcoal briquettes. I don’t recommend the briquette method due to the costs of the briquettes and the lack of availability of charcoal briquettes in some areas of the U.S. during the winter months.