12 January 2010
Wind Power Integration
Wind power is fluctuating and unfortunately not at all in time with the electricity demand. Doubling the wind power in Denmark will therefore make it more difficult to provide electricity in accordance with the consumers' demand pattern.

The integration of wind power implies interesting and challenging jobs.

There is a quite polarized debate on wind power, particularly abroad. Keen supporters of wind power play down the need for special measures. They claim that all problems will be dissolved in the large European market.

This is pure ostrich policy. Maintaining high security of supply, cogeneration of electricity and heat and efficient utilisation of wind power at the same time will require new local measures to be developed in due time.

The Danish transmission system operator, Energinet.dk, has made a large effort for analysing and describing the possibilities for integration of wind power.

Moreover Energinet.dk has financed a project with participation of external experts, see EcoGrid.dk.

Experts in many countries have worked eagerly to solve the integration problems of wind power. New power system architecture has been introduced as a "Smart Grid" which is supposed to offer users of the power system new innovative services and mobilise flexibility which was so far unexploited.

It has been claimed that utilising overflow electricity is no problem because it can be stored in Norway. This solution should be chosen when it is profitable, but congestion or economy may suggest other solutions. The Norwegian service has a cost and the price depends on the Danish alternatives. Therefore domestic alternatives can be of great value.

I am particularly interested in Denmark's opportunity to create cheap and efficient domestic alternatives by coordination with the district heating systems. Hot water for heat supply for many hours is stored in pipes and tanks in the district heating systems. The hot water is a significant storage allowing a very flexible operation of the power plants.

If this flexibility remains unexploited wind power and CHP plants will compete for insufficient electricity consumption. In addition we make an effort to save electricity. The result can be overflow of electricity, reduced cogeneration and more heat production on backup boilers.

Optimal utilisation of hot water storages can together with electric heating of water for district heating eliminate about half of the problems created by increasing wind energy penetration from 10% to 50% of the electricity consumption.

Great things are expected from the use of electric cars and more advanced technologies. These solutions will contribute as well, but not until mature "smart grid" solutions are ready for practical use in Denmark.

It is easy to describe the coordination with the district heating systems in general terms. I also wanted to quantify the effects of this solution. Therefore I made a model for rough calculations. The first results indicate considerable new flexibilities for Dansih market participants in the international electricity market.

See the notes below.


* 50% Wind Energy: Options and Challenges - 3 Dec 2009
* Wind Power and CHP: Conflict or Interaction? - 10 Jan 2010
* Making Renewable Energy Useful - 19 Jun 2010
* Combining Smart Grid Measures - 27 December 2010
* Wind Power and District Heating - Translation of article, Fjernvarmen 4/2011

Opdateret d. 10.5.2011