Do we need the power stations?

About the changing role of power stations in the energy system and the great potential of converting the power stations to run on biomass.

By Jakob Askou Bøss Vice President, DONG Energy

As consumers, we take a reliable energy supply for granted – and that’s how it should be. But a large part of Europe’s energy supply will be ready for retirement within the next 20 years and at the same time, the increasing global CO2 emissions put pressure on the climate. 2014 was the warmest year ever. Therefore, the need to renew the energy supply provides a unique opportunity for steering Europe’s energy in a greener direction and for converting the supply to a higher degree of renewable energy.

The conversion means that the role of the power stations in the energy system will change. The power stations are the flexible co-player for wind turbines, as they are able to take over swiftly when the wind is not blowing and the sun is not shining, and they are also able to quickly reduce production to a minimum when solar and wind power can fulfil the electricity demand. Moreover, they deliver district heating to many Danish households at the same time.

From coal to biomass
We need the power stations’ flexibility for many years to come, but as our coal-fired power stations are a considerable strain on the climate, we need to use less coal. Since 2006, we have reduced our coal consumption by 2/3 in DONG Energy, primarily because we have taken a number of outdated power stations out of operation. At the same time, we are in the process of a historic conversion of the Danish power stations to use biomass as fuel. At present, we are converting the Studstrup Power Station near Aarhus and the Skærbæk Power Station near Fredericia to use biomass as fuel. When the two projects are completed in 2016 and 2017, more than 400,000 Danish citizens will receive green heat from the two power stations.

Naturally, we must ensure that the biomass we use is produced in a sustainable way so that the CO2 emissions are actually reduced. The wood that we use at our power stations is primarily so-called waste wood and thinning wood, consisting of the top of trees, branches, crooked trees and thinning trees which have been planted to shelter other trees, and which are most often regarded as waste wood. But waste wood is excellent for wood chips and wood pellets that can be used at our power stations.

Conversion of power stations is common sense
In DONG Energy, we have established a programme where we make demands on our suppliers to ensure that the forests, from which our waste wood and thinning trees originate, are replanted and run in a sustainable manner to ensure that the ecosystem and the biodiversity are maintained. Our suppliers must be able to document that they live up to our requirements, and independent auditors supervise them. In this way, we ensure that we use the right type of biomass. Namely the biomass which results in significant reductions of our CO2 emissions, and which makes power stations a de facto green player in the conversion of the energy system.

The conversion of the existing power stations to use biomass as fuel is financially sensible compared to other CO2 neutral energy technologies. Moreover, biomass-fired power stations have the advantage that they are the only adjustable source of renewable energy we have. It is an important prerequisite for ensuring that we, as consumers, can continue to take reliable energy for granted in future as well.

Denmark’s future green energy system is based on a lot of wind power and green power stations operating on sustainable biomass. Denmark is the world leader when it comes to both technologies, providing not only green energy to the Danes, but also many export orders to Danish companies.

Source: DONG Energy /State of Green