Pellets are very ecological fuel. Its combustion does not cause additional CO2 emissions, because the amount of carbon dioxide produced during combustion is equal to that in the process of photosynthesis, plants are planted on the site burnt.
Pellets are an excellent alternative to heating oil and coal burned in small boilers, which contributes the most to environmental pollution from all fuels. In comparison with oil - mainly for economic reasons. The cost of producing a unit of energy from wood pellets is half as high. An additional incentive may be that by switching to pellets, you do not need to replace the stove. Just buy the right burner and install it with the existing boiler instead of the oil burner. It will work with the boiler just like an oil burner and thanks to the automatic fuel supply system it will ensure maintenance-free operation of the device.
In comparison with coal and coal stoves, the price of energy produced from wood pellets is a dozen or so percent higher. However, it is worth considering replacing the old coal boiler with a pellet boiler. In addition to the undoubted contribution to environmental protection, it will allow to modernize the installation and much more convenient than other solid fuels, and at the same time cheaper than using it in the case of gas. It is also possible to install a solid fuel at the boiler (coal, coke, wood), just like with an oil burner, which will improve the boiler's operation and adapt it to the burning of pellets.