Biomass

Plant-based raw materials have captured solar energy in the form of chemical compounds, which can provide us with energy by burning them or by converting them into usable fuels. Since during this process plants remove CO2 from the atmosphere which is once again released when used, this is termed as a climate neutral source of energy.

Biomass is understood to mean crops that are cultivated specially for energy supply, or waste streams from agriculture, cattle breeding, industry and households that result from plant or animal materials. Biomass is not only (potentially) attractive as an energy supply; the chemical industry will increasingly have to rely on plant materials, if petroleum becomes increasingly expensive or even runs out.

The type of biomass that is used determines to a large extent how much is being saved in terms of the carbon dioxide emissions that otherwise would have been released as a result of the use of fossil fuels. In areas in which intensive agriculture is practiced, for example, artificial fertiliser is used in the production of fuel-crops. The production and application of artificial fertiliser leads to greenhouse gas emissions, which can considerably limit the favourable effect of plant materials, depending on the type of crop. For instance, biodiesel from rapeseed delivers an extremely modest advantage in terms of CO2, however it does of course contributes towards reducing our dependence on petroleum imports. The joint burning of wood-based materials in power stations is an example of biomass usage with a much greater environmental efficiency.

Currently, ‘modern biomass’ contributes approximately 2% towards the energy requirements in developed countries. This may seem like a small percentage, but along with water power, this means that biomass is the most important renewable energy source. In developing countries, 2.5 billion people are still dependent upon wood, manure and other forms of organic fuels for traditional applications, which brings the total contribution of biomass to the worldwide energy supply to approximately 10%.

The aim of the European transport fuel directive is that in 2010, 5.75% of the fossil fuels used in road traffic in Europe will have been replaced by biofuels. In the coming years, we will therefore witness a sharp increase in the use of biofuels and the Netherlands will be able to establish an important position in this process for the transit of biofuels to the European hinterland. For the time being, food crops such as sugar cane and maize are used for bio-ethanol and, to a lesser extent, rapeseed is used to produce biodiesel: the 1st generation of biomass. Imports from outside of Europe will be necessary in order to achieve the objective. The transit function of the Netherlands will also be reinforced by the increasing amount of interest being shown in the joint burning of biomass in power stations.

It is still unclear, however, how strongly the use of biomass will develop in the longer term and which crops and technologies will then become dominant in biomass. Many scenarios assume a considerable contribution of up to a possible 20 to 30% of the energy supply in a few decades from now. At the same time, however, the worldwide demand for food will also increase. The price of grain products in South America is at present already reacting strongly to the demand for biofuels from the West. The prevention of competition between energy and food supply therefore merits serious attention.

The new technology with which residual flows from food cultivation, industry and households can be converted into energy, fuels and chemicals, is however very promising. This is referred to as the 2nd generation biomass conversion. Research into new processes that can be applied both in an economically and environmentally sound way will increase sharply in the coming years. Research is also being conducted into (new) crops that flourish well on barren ground and that do not therefore put pressure on the quantity of agricultural land available for food production. In addition, algae production at sea, for example in new offshore wind farms, would appear to be an attractive option, although research into this is still in the very early stages. Furthermore, it is highly important that research into new possibilities for the application of biomass not only focuses on technology, but also on the social and environmental consequences ‘from the field to the tank'.