Articulation between the use of pellets and wood chips for biomass boilers - Final report + Synthesis + Summary of the study

The consumption of wood pellets from collective and industrial boilers in France accounts for only about 5% of the French pellet market, which is largely dominated by domestic uses in private stoves and boilers, and only 2% of the energy entering collective and industrial boilers (while the number of pellet boilers accounts for almost 20% of the total), the vast majority are supplied by shredded wood (wood chip, wood industry related products, chipped branch-wood). Considering this observation, it is important for the wood-energy sector to better know the boilers using wood pellets and to accompany their development through a better understanding of the logic of their realization and an in-depth knowledge of the possible articulation between the use of pellets and wood chips. This is the condition for offering a complete range of solutions and thus reaching a wider audience. The purpose of this study is to meet this expectation. Interviews with experts and plant owners have identified that wood chip and pellet solutions are very often studied in parallel. The advantages of pellets (energy density and homogeneity) make them best suited in case of limited land availability for the realization of the boiler (compact equipment) or in case of difficult accessibility of the fuel storage silo for deliveries (using a blower truck) and, finally, the ease of operation of a boiler with pellets can also influence the choice of the owner. When there is no technical difficulty in making a wood chip boiler or willingness to use any other fuel, the arbiter is the overall cost of heat. A constant then returns pellets and wood chips are generally more competitive than domestic fuel oil or propane, however, it is often the opposite with natural gas. When the two wood solutions are compared to each other, it appears that pellets often have the advantage for smaller powers (usually less than 150-200 kW, the observable range can be as high as 400 kW or 500 kW) and that their relevance to wood chip installations increases the more irregular the use of buildings is. This is indeed confirmed by the simulations carried out in the context of this study, which specify the situations of economic relevance of the pellet installations in relation to the use of wood chip. Thus, the priority development target for pellets (beyond domestic uses) is small-power dedicated boilers for buildings with irregular and high heating needs (schools, tertiary premises) or medium (collective housing),less frequently high (health and social establishments) and especially in areas not served by natural gas. The use of pellets can also be considered for the industry, mainly for the heating of the premises and for the process (small cheese factories in particular). Similarly, heat networks are a potential target, but existing facilities are few and situations are diverse (replacement of coal, use in addition to a boiler with wood chip, use as a base for an eco-neighborhood)