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Category — Denmark

Peeling Away the Onion of Denmark Wind (Part IV – CO2 Emissions)

[Editor's note: Parts I-III provided insight into the complexities involved in any analysis of the Danish electricity system, showing (1) how unique the Denmark situation is, (2) that the details of electricity exports and imports must be understood for each of Denmark’s trading partners, (3) the likelihood that most of Denmark’s wind production is exported, and (4) an indication that the upper limit for manageable wind penetration is in the mid-single digits as a percent of domestic demand. Part IV now looks at the impact on CO2 emissions.]

Figure 1 is a simple look at CO2 emissions and wind electricity production, which explains the claims made by wind proponents based on a superficial examination of the information. Figure 1 shows what the Danish Energy Agency (DEA) reports based on an “adjustment” of actual CO2 emissions. 2007 was a windy year and 2006 was a notably low wind year.

Figure 1 – Wind-generated electricity and CO2 emissions from electricity production in Denmark for the period 1990-2008. 1990 is the base year for Kyoto performance measurement. CO2 emissions are adjusted based on net exports of electricity.

This looks convincing on the surface, but is not substantiated by closer examination. There are many reasons not to look to the relationship between wind electricity production, or any electricity production, and CO2 emissions as evidence of cause and effect, and these will be covered later.

But first, it is important to understand what the actual (or “observed” using the DEA terminology) CO2 emissions in Denmark are before “adjustment”. [Read more →]

October 29, 2010   9 Comments

Peeling Away the Onion of Denmark Wind (Part III – Wind Electricity Used in Denmark)

[Editor's note: Parts I and II set the stage for the development of some conclusions about how much wind electricity Denmark exports, which will be provided in this post. The impact of wind on CO2 emissions  is addressed in Part IV]

To further reduce the total amount of information to a more manageable level, the following is a look at this from the point of view of Denmark’s electricity import/export flows for the most recent “normal” year (2004), dry year, (2006), and a wet year, (2007), these conditions being the main driver of exports. This is shown graphically in Figures 1-3, starting with a normal year. In these charts numbers may not exactly balance due to rounding. Note in particular the net export levels, which are typical for each type of year.

It must be remembered that most of these activities can take place at different times during the year, month or day. For example wind generation is usually strongest at night so Norway and Sweden could be taking Danish wind at night and delivering hydro-generated electricity during the day. Alternatively, Nordic hydro-generated electricity could be being used extensively to balance the remaining large amount of Danish wind for domestic consumption within Denmark or export to Germany.

As Figure 1 shows, in normal years, the flow through Denmark is relatively balanced between imports and exports with its electricity trading partners.

Figure 1 – Danish imports and exports of electricity in 2004, in a normal year, that is when there are not significantly wet or dry conditions in the Nordic region.

Here there is ample opportunity for the export of Danish wind to Norway/Sweden. Bach calculates that about 60% of wind from West Denmark, which has about 80% of total Danish wind capacity, is exported. Wind exports from East Denmark are typically less than that for West Denmark, and Andersen notes that there is more clearly an export of fossil fuel generation from East Denmark. [Read more →]

October 28, 2010   2 Comments

Peeling Away the Onion of Denmark Wind (Part II – Details of Exports and Imports)

[Editor's note: Part I explained the unique character of the Denmark electricity situation as background to a more detailed look at Danish exports/imports of electricity and CO2 emissions. This post and Part III will focus on exports/imports to show the larger role that wind is having in exports. Part IV will then address CO2 emissions, providing the conclusion to this series.]

There is a range of views on the amount of Denmark wind-generated electricity that is exported. Any that rely on annual net exports should be very suspect. Table 1 provides a summary of notable analyses, all of which at least use hourly net exports. All must be read for any comprehensive understanding.

Table 1 – Summary of Notable Analyses of the Amount of Wind-Generated Electricity Exported by Denmark.

Bach and Andersen firmly dispute the CEESA critique of CEPOS, and both show substantial wind exports. Bach makes an interesting comment in his paper:

“Based on these observations it could be said that Germany and Denmark together have solved the integration problems for about 7% wind energy, but only due to the common access to the regulation capabilities of the other Nordic countries, notably hydro power in Norway.”

The case is strong for substantial exports of Denmark wind production as shown by Bach and Andersen, and supported by others such as Sharman. [Read more →]

October 27, 2010   3 Comments

Peeling Away the Onion of Denmark Wind (Part I)

[Editor’s note: This series is an extensive technical analysis of wind electricity in Denmark. The intent is to develop: (1) plausible conclusions without resorting to extensive mathematics (except that provided by others) , and (2) a framework within which to evaluate other claims of emissions relating to wind backup from fossil plants.]

According to wind proponents, Denmark is a model of wind energy use for electricity generation to be emulated. It is claimed or suggested that:

  • Denmark gets about 20% of its electricity from wind. [Note: This number is generation, not usage, which is a crucial distinction with negative implications for the wind lobby's argument.]
  • Reduction in CO2 emissions is due in large part to increased wind electricity production.

These conclusions are superficial at best and invalid at worse. The analysis required to show this, however, is extensive and technical because the Denmark power market is very unique and wholly unlike the market in the U.S. or the UK.

A Note on Sources

Recently the American Wind Energy Association (AWEA) has made claims about Denmark, based on data from the U.S. Department of Energy (DOE). This is at least one step removed from the source for most of the information in this series, the Danish Energy Agency (DEA). Its report 2008 Energy Statistics, and associated Excel worksheet tables, is one of the best sources of comprehensive information on the Denmark electricity situation.

There is another source with very detailed information, Energinet.dk, which is the Danish national transmission system operator for electricity and gas. It has been used for some more extensive mathematical analyses that are referenced here, for example Bach. As will be seen, even these have limitations because of the unique and complex nature of the Denmark electricity system.

As a result, this analysis purposely based more on logic than precise mathematical treatments, but building on the mathematical work of others. The limitations in both cases are the complexities, which will be explained, but both approaches provide insights into the Denmark case. In the final analysis, all available evaluations of the wind-generated electricity (this will frequently be referred to as just “wind”) realities in Denmark are speculative, but some more plausible than others, and readers are left with having to draw their own conclusions.

Claims based on a quick reference to a few selected statistics should be seriously questioned, and this series provides a context within which all claims can be evaluated. [Read more →]

October 26, 2010   8 Comments

Simulations or Country Experience? Spain, Denmark, and NREL in the Renewable Energy Controversy

For a long time, fans of renewable electricity have made their case by running simulations. Input the right data and (more importantly) the right assumptions, impose a renewable portfolio requirement or carbon plan, compute 30 years forward, and walk into a clean, fully employed future. Just close your eyes, click your heels, remember
to believe, and elect the right federal government.

Then reality intervened in the form of two country-wide case studies.


More than a year ago, this column scooped the mainstream media with the truth about Denmark’s 20 percent wind generation. The country actually uses less than half of that power, but can keep the machines spinning thanks to (export) connections with the coal-based German grid and the nuclear- and hydro-based Scandinavian RTO.

For all this, the little mermaid enjoys the highest power costs in Europe. There is now an excellent report with lots of data by a think-tank there called CEPOS, which occupies roughly the same position that the pro-market Cato Institute does in Washington. (Disclosure: I am a Cato adjunct scholar and have taken money from them. Cato itself, like CEPOS, is supported almost entirely by private—as opposed to corporate—money.)

The study points out the sad fact that in a few years Denmark’s neighbors will be producing enough of their own wind power that their grid will have difficulty accepting Denmark’s, even if it comes gratis.


Spain is a more tragic story. [

October 1, 2009   2 Comments