Coal, firewood, fuel briquettes: how to heat a solid fuel boiler

Let’s talk about the better, the more profitable it is to heat a solid fuel boiler. Among the most popular options are firewood, coal and fuel briquettes, pellets. Let’s compare the features of using all three of these types of fuel, talk about the pros and cons, main characteristics, and summarize.

Let’s clarify right away that sometimes owners of solid fuel boilers have no choice. For example, there are wood-burning boilers, and there is equipment designed for the use of pellets, and of a certain size. Wood-burning boilers can most often also work on coal, but still, before making a choice, this moment must be clarified and taken into account.

However, the most popular are universal solid fuel boilers that can work successfully on coal, wood, and fuel briquettes. Therefore, the question of the choice of fuel immediately arises before the homeowner..

Let’s first compare the most obvious indicator – specific heat of combustion:

Firewood	Coal	Briquettes-pellets
The specific heat of combustion of freshly sawn wood is 1940 kcal / kg or 2.2 kWh	The specific heat of combustion of anthracite is 6700 kcal / kg or 7.8 kWh	The specific heat of combustion of peat briquettes is 4200 kcal / kg or 4.9 kWh
The specific heat of dry wood is 3400 kcal / kg or 3.9 kWh *	Specific heat of combustion of coal 6450 kcal / kg or 7.5 kWh	The specific heat of combustion of wood briquettes is 4100 kcal / kg or 4.7 kWh
	Specific heat of combustion of brown coal 3100 kcal / kg or 3.6 kWh	The specific heat of combustion of straw briquettes is 3465 kcal / kg or 4 kWh
		The specific heat of combustion of sunflower seed hull briquettes is 4320 kcal / kg or 5 kWh

* average indicator for firewood. The highest specific heat of combustion will be in beech and oak, the lowest in willow and poplar. Conifers are roughly in the middle.

The second important factor is how much this or that fuel burns:

• Coal – up to 12 hours.
• Fuel briquettes – about 7-8 hours.
• Firewood – 2 to 6 hours.

Once again, we admit that we took the average indicator. Again, it all depends on the type and quality of fuel, for example, dense briquettes of wood dust will burn longer than straw or sawdust.

In addition, a lot depends on the efficiency and quality of operation of the solid fuel boiler itself, so find out all its characteristics by making a choice.

It seems that everything is clear. Firewood has the lowest specific heat of combustion. In addition, they will burn out the fastest. Therefore, they turn out to be the most unprofitable type of fuel. Yes, they have disadvantages:

• It takes two years to dry for them to burn normally in the boiler..
• Self-preparation of firewood is a time-consuming process, you need to chop, chop, saw.
• When storing, they require certain conditions, the correct firebox, take up a lot of space.

So, it turns out, we cross out the wood? Do not hurry! Firstly, even if you decide to use more high-calorie coal, which will have to be thrown into the boiler once or twice a day, you still need firewood for kindling. In addition, a big plus of firewood is a much more affordable price in comparison with fuel briquettes, unless, of course, you do it yourself. I already wrote about storing firewood on the site.

In addition, coal has a higher ash content, and its storage, carrying and use is black coal dust on hands, clothes, indoors..

Another important point when choosing a fuel for a boiler is the region. In some regions of our country there are so many forests that it is not a problem to stock up on firewood or buy them for a cheap price. In others, there are coal mines nearby, where you can prescribe fuel inexpensively and with free shipping. In third regions, the production of briquettes is developed, for example, from straw or wood waste. Therefore, very often the choice of fuel is determined precisely by its availability, and not by other factors..