It is stated in the SVM government foundation that 'Denmark must be a green pioneering country that sets and fulfills ambitious climate goals and climate efforts and in this way inspires other countries to follow suit.' But we in Denmark have not reached the goal of converting our society from burning fossil fuels to renewable energy. In fact, 54 percent of Denmark's total energy consumption still comes from fossil fuels – that is, oil, coal and gas. Another unpleasant truth is that a large part of renewable energy also consists of burning something.

Many people think of Denmark as a country with a lot of wind energy, but two-thirds of our renewable energy comes from burning biomass. This is mainly the burning of wood, but it is also the burning of biodegradable waste for the production of electricity and district heating, biogas for industry and heating and straw for district heating.

Consumption of wood burning

If we delve into the burning of wood, we primarily burn three different types of wood. These are wood pellets that are primarily used in cogeneration plants, where both electricity and heat are produced by burning the wood pellets in a boiler.

It is wood chips that are primarily used in district heating plants, where you burn the chips to heat up water for district heating. And then there is firewood that is used to light wood-burning stoves. This has major consequences for the aviation association, but for now I am dealing with burning wood pellets and wood chips at the works.

If we start by investigating where the wood comes from, it becomes clear that Denmark's consumption depends on imports. In fact, we import 95 percent of the wood pellets, one shows analysis from the Danish Energy Agency. In 2022, 16,5 percent of wood pellet imports came from the USA, 10 percent from Russia and around 40 percent from the Baltic countries. About half of wood chips are imported, while we get the other half from Danish forests.

Problematic level

The Danish consumption of wood has thus reached a level where other countries have to cut down their forests so that we can burn wood pellets and chips in Danish boilers. The UN's climate panel (IPCC) has estimated that there is 10 GJ of biomass available per year. world citizen. In Denmark, we use approx. 30 GJ, so the amount we burn is far from sustainable.

In the energy sector, the burning of biomass is considered CO2-neutral, and this is determined by international conventions in the EU and the UN. The climate impact is calculated in the LULUCF sector, so it is important to remember that there is a CO2 emission associated with burning wood. It actually takes decades for a newly planted forest to absorb the same amount of CO2 as the felled forest did. If the alternative was to leave the wood to rot in the forest rather than burning it, it could take between 40-100 years before the emissions could be compared. Wood takes decades to absorb CO2, which is released again in split seconds when we burn it.

Some may remember photosynthesis from biology in elementary school, where plants, and thus also wood, convert water and CO2 into oxygen and sugar. When we burn the wood again, there will be an immediate emission of CO2. And that CO2 is no different to that emitted by burning fossil fuels and is therefore also a greenhouse gas emission into the atmosphere.

CO2 emissions from burning biomass have increased as we burn more in Denmark. Wood consumption has increased by 60% in the last 15 years and continues to rise.

It is problematic that burning wood has become Denmark's substitute for burning fossil fuels. Especially when it was presented as a transition fuel 12 years ago to get rid of coal. But now the time is different, so something should be done at Christiansborg to push for the phasing out.

CO2 tax is essential

In fact, a subsidy of 15 øre per kWh for electricity production by burning wood biomass and indirect support because biomass is exempt from energy and CO2 taxes, which distorts competition.

Instead, a CO2 tax on the burning of wood biomass should be introduced, so that it becomes less advantageous to burn it. In the first instance, we must have put a price on the CO2 emissions from burning wood, which requires an emission factor.

It can be difficult to agree on - research points to anything between 20 and 100 kg CO2/GJ, with the Climate Council proposing an emission factor for biomass of 39 kg CO2/GJ. But even a conservative emission factor will have a big impact.

We must stick to the fact that wood is a transitional fuel and get a political strategy that can ensure a real phasing out of wood biomass.

The strategy should contain initiatives that can ensure that no investment is made in new biomass plants. For example are there still heating plants that buy wood-chip boilers rather than heat pumps because they calculate in a conservative way. The strategy must also contain a phase-out plan for the existing biomass-fired plants.

It is absolutely essential that the strategy also contains incentives to leave some of the wood in the forest rather than burning it down. Denmark has the lowest level of dead wood in European forests, which greatly affects biodiversity.

This debate entry was published in Ingeniøren GridTech on 10 September 2024 and is written by Julie Abrahams, senior advisor, Green Transition Denmark