Consumption of solid wood fuels started to decrease – the burning of forest chips increasing
According to the preliminary data of the Natural Resources Institute Finland (Luke), a total of 30 million cubic metres, or 60 terawatt hours, of solid wood fuels was consumed by heating and power plants and in small-scale burning. This showed a decrease of two terawatt hours from the previous year.
Heating and power plants consumed 22.8 million cubic metres of solid wood fuels, with their energy content totalling 44.7 terawatt hours, down by five per cent from the previous year.
“Even though the discontinued importation of energy from Russia and increases in the prices of other fuels consumed at heating and power plants increased demand for domestic wood fuels, the need for heat generation was lower, and the lower production volumes in the forest industry reduced the availability of forest industry by-products,” says Tuomas Niinistö, senior statistician at Luke.
Large amounts of fuelwood were also consumed in small-scale housing and on farms. The burning of fuelwood in small-scale housing and on farms accounted for 6.9 million cubic metres, or 15.3 terawatt hours, of the consumption of wood in energy generation. The data is based on a sampling survey for the 2016/2017 heating season and will be updated later in spring 2023.
Consumption of forest chips continued to increase
The changes taken place in the energy markets were especially reflected in the consumption of forest chips, meaning wood sourced directly from forests and burned after chipping. The consumption of forest chips in heating and power plants has increased considerably in Finland during last two decades and has stabilised in the 2010s at around 7-8 million cubic metres per year. In 2021, consumption started to rise again, as 9.5 million cubic metres of forest chips were consumed in heating and power plants.
Despite the decrease in the total consumption of solid wood fuels, heating and power plants consumed more forest chips than ever before in 2022, totalling 10.2 million cubic metres.
“The consumption of forest chips increased in combined heat and power generation, that is, at the largest CHP plants. They consumed 6.6 million cubic metres of forest chips. In heat generation alone, the consumption of forest chips even started to decrease slightly,” says Niinistö.
In addition to heat and power plants, a total of 0.6 million cubic metres of forest chips were consumed in small-scale burning, including chip-based heat plants on farms. Heating and power plants, and small-scale burning, consumed 10.8 million cubic metres of forest chips in 2022.
Majority of forest chips made from small-diameter trees
More than 60 per cent, or 6.4 million cubic metres, of the forest chips consumed at heating and power plants were made from small-sized trees, including pruned and unpruned stems, and pulpwood.
“During the last 12 months, it has seemed that the growing demand for energy wood also causes wood suitable for processing in the forest industry to be burned. If wood has been sourced and harvested as energy wood, the percentage of wood usable as raw material for forest industry cannot be deducted from the statistical data collected,” says Niinistö.
Three million cubic metres of logging residues collected at regeneration felling sites were burned as forest chips. The volume of large-sized trees consumed by burning, fairly typically consisting of decayed logs, was 0.6 and that of stumps 0.3 million cubic metres.
Forest industry by-products are an important source of energy
Despite the increased percentage of forest chips, nearly half of all solid wood fuels burned in heating and power plants consisted of various forest industry by-products. Forest industry products generate a certain volume of side streams characteristic to each product. This is why the use of by-products as energy fairly closely follows forest industry production volumes. As forest industry production decreased, the consumption of its by-products decreased by 15 per cent from the previous year to 10.9 million cubic metres.
The majority of by-products consisted of bark, of which 6.4 million cubic metres were consumed. Industrial chips, various types of sawdust and other unidentified residues accounted for 4.5 million cubic metres.
In addition to forest chips and solid forest industry by-products, solid wood fuels include recycled wood and wood pellets, whose consumption totalled 1.6 million.
Black liquor, generated as a pulp industry by-product, is another highly significant source of energy alongside solid wood fuels.
Information about the statistics
The statistics only cover the annual consumption of solid wood fuels. In addition, the consumption of wood in energy generation includes spent liquors of the forest industry, including black liquor. Statistics Finland is responsible for compiling and publishing statistics on their consumption.
Information about the consumption of solid wood fuels is collected from heating and power plants once a year. The figures representing the small-scale burning of wood are based on a separate sampling survey. The data presented herein is preliminary, and the final statistics will be published in autumn 2023.
