Biomass covers a wide range of raw materials of biogenic origin. Here we focus on ‘bioenergy’, which refers to the use of biomass as an energy carrier or as a substitute for non-energy consumption of fossil fuels. Bioenergy can contribute to the energy transition because the CO2 that is released during combustion is not included in the required reporting of greenhouse gas emissions (GHG)). Instead, it is assumed that the CO2 released during combustion is recycled as a forest and/or crops regenerate causing no net addition of CO2 to the atmosphere. Incidentally, emissions must be reported for the removal of biomaterials from the carbon stock of the natural environment, whether or not their use is for energy purposes. These emissions fall under the item Land Use, Land Use Change and Forestry (LULUCF). This is disputed as some argue that, in addition to or instead of residual streams from forestry, wood from entire trees from forests would be used and there is doubt about how long it will take before CO2 is taken up again by growth. Another concern is the clearing of primeval forests to make way for agriculture or forestry. The Netherlands applies strict sustainability criteria for the use of subsidized biomass for energy applications, taking these considerations into account. The controversial co-firing of woody biomass in coal-fired plants concerns a limited part of the total use of biomass in the Netherlands. Currently, the share of renewable energy in total final energy consumption in the Netherlands is 7.4%, compared to 4% in 2010. The share of biomass in total final energy consumption has grown from 3 to 4.5% in the same period. The share of co-firing in coal-based power plants remains very low, i.e. 0.6%. As of 2016, biomass for co-firing has been added to the Dutch Stimulation of Sustainable Energy Production (SDE+) scheme. Therefore, the share of co-firing in coal-based plants is expected to increase again in the coming years (up to the set maximum of 25 PJ of produced energy per year). The sustainability of biomass is further discussed in a “hot topic” on this website.
Biomass from plants includes, for example, wood (residual material from wood extraction from which beams and planks can no longer be sawn), pruning waste and residual flows from the food industry. There is a huge potential for woody biomass in Europe. Biomass of animal origin, for example, concerns manure that is fermented into biogas. For liquid biofuels, a distinction is made between first, second and third generation biofuels. First generation biofuels come from food crops such as corn, rapeseed, palm oil and sugar cane. Second generation biomass consists of residual streams that do not compete with agricultural land for food crops. Third generation biomass involves new developments, such as seaweed.
Biomass can be solid, liquid or gaseous and can be used for all kinds of applications. Biomass can be used for heat production in homes and other buildings, but also for process heat in industry. It can be used for electricity generation by co-firing solid biomass in coal-fired power stations, via fermentation as biogas in CHP plants or in waste incineration plants. In the transport sector, bioethanol is blended into gasoline and biodiesel into diesel. Biodiesel can also be used without blending. Bio-liquified natural gas (LNG) is also currently used in transport, and biomethane is blended into the gas network. An important aspect of bioenergy is that its availability is not weather dependent, which is the case for wind and solar energy. This means that bioenergy can play a role as CO2-neutral adjustable electrical power.
The petrochemical industry will have to make the transition from petroleum to other, non-fossil fuel based raw materials, because fossil fuel-based products, such as plastics, will eventually end up in the waste incinerator and generate CO2 emissions. Material of biological origin is a suitable candidate for this. For scaling up the biomass market, its use as fuel can serve as a starting point. In the future too, there will always be a part that cannot be used for material production, and that can still find a useful application as an energy carrier. The idea is to prioritize the most valuable applications over less valuable ones, so preferably make them into chemical products and only the non-suitable part for energy applications.