Wednesday, 21 October 2015

The Myth of Denmark as a self sufficient renewables success

“When you see the wind blowing in your neighbourhood and the turbines moving, you know that you are making money, which is great incentive to support wind power,” Mortensen observes, adding that polls show around 90 per cent of Danes are in favour of increasing wind energy production.

The outcomes to date are impressive. Denmark is now generating close to 40 per cent of its annual electricity needs from wind and on some days production reaches as high as 120 per cent of needs. An efficient market exchange operates with its neighbours in Germany, Norway and Sweden to take advantage of fluctuating supply and demand, as dictated by weather conditions. - Irish Times, October 2015

Much has been made of Denmark in the Irish media of late and indeed by politicians who are holding it up as an example for Ireland to follow in terms of wind energy.

Unfortunately, much spin comes out of Denmark, which coincidentally sells alot of wind turbines.

Danish Wind Subsidy Scheme Vs Irish Wind Subsidy Scheme -
why the Irish wind industry should be careful for what they wish for

The subsidy scheme for wind is slightly different there :

A price supplement is provided of DKK 0.25/kWh for the sum of electricity generation for6,600 full load hours and for electricity generation of 5.6 MWh per m2 rotor area. The pricesupplement is reduced for each DKK 0.01 the market price of electricity exceeds DKK0.33/kWh nominally, and, thus, the supplement altogether lapses, if the electricity pricereaches a cap of DKK 0.58/kWh or more in current prices 

This works out at a subsidy of €30/ Mwh on top of the market price, but once the market price goes above € 40/MWh there is a reduction in subsidy, with no subsidy at all once the market price hits
€ 80/MWh. Aswell, this subsidy only applies to 6,600 hours of operation i.e. 75% of the year. After this, the wind farm receives the prevailing market price in the region like everyone else. As a result, it is not uncommon for wind farms to shut down once the subsidy runs out as they don't receive enough from the market to cover their costs :

 Now owners of wind turbines complain that spot prices do not even cover maintenance cost - PF Bach, Denmark 2015

Somehow I can't see Ireland adopting the Danish subsidy scheme, yet, Ireland is keen to copy everything else from Denmark in terms of wind integration.

Let's take a look, step by step, at the reality of Denmark's grid operation in 2015:

  1. Denmark has 3.5GW of onshore wind, around 1GW more than Ireland. On top of this they have 1.2GW of offshore giving a total of 4.7GW, compared to Ireland's 2.5GW. 
  2. Nearly 40% of the electricity mix was from wind in 2014. Strong interconnections was the main factor behind this achievement. However, this figure includes the quite high amounts of wind that is exported so the amount of wind energy actually consumed in Denmark would be less than this figure in reality.
  3. Denmark has eight interconnectors compared to Ireland's two.
  4. There are many more interconnectors planned in Denmark. It is envisaged that these will make up for the shortfall in dispatchable capacity. Ireland has a surplus of dispatchable capacity. 
  5. Denmark is heavily reliant on CHP for dispatchable plant which is declining meaning that Denmark will no longer be self-sufficient in a few years. By 2018, it will be heavily reliant on expensive imports through interconnectors. The reality is that Denmark is far from the "self sufficient renewable success" portrayed by the media here in Ireland. If Denmark had not access to the unique Nordic system, they would have to build more power stations, like the Germans, English and Dutch. 
  6. Export to import exchanges can change from 60% export to 75% import in the space of half a day (such as 9th July 2015)
  7. It is widely assumed that export prices are practically Zero while import prices are very high. Hence, why exporting wind power does not pay (unless you find a sucker willing to pay the subsidy). 
  8. 99% of (their neighbour) Norway's power comes from Hydro. This can be ramped up and down at the touch of a button, without losses in efficiency and therefore is perfect for back up for wind energy. But it is very expensive and as per point 7, the Norwegians regularly fleece the Danes for using it.  Ireland has very little hydro and neither does the UK or France. Gas turbines, by contrast, are not designed to run on low operation levels during high periods of wind, Nuclear plant are designed to run at baseload i.e. constant output. So the Danes are in a unique position viz a viz their wind generation and access to substantial amounts of hydro power. Ireland is not comparable in any way whatsoever.
  9. Denmark has the highest electricity prices in the EU. Not surprising, considering the above.
Hydro dam in Norway

Sources : 


  1. I wonder what proportion of Denmark's interconnection is HVAC and what portion is HVDC. Alternating current is much more valuable because it can be used 100% to power one entity from a neighbouring one. It controls inertia and frequency. Direct current provides working current, but does not help stabilise frequency. So HVDC must be kept below 50% of the importing entity's demand. Availability of hydro power depends on the topography of the land and on precipitation (rain). Where it is available, plants, fields, forests, soak the water releasing it to small streams. These streams flow into larger ones which are dammed to create even more stored water. The availability of water can be forecast very precisely, so there is no need to keep fossil plant at the ready. It was first used to power New York from Niagara falls. It takes 5 tons of water falling 100 meters to produce 1 kwh of electricity. The dense fluid nature of water and its non polluting character make it ideal. Dams damage and destroy fish breeding. It is hard on the environment. Advocates of wind energy try to link the two as renewable, but they are totally different.

    1. The two systems - Ireland and Denmark - are entirely different. The below is from PF Bach on this subject :

      "The two parts of Denmark (west and east) are operated in synchronism with the German and Swedish power systems respectively. Security rules are coordinated within the continental and the Nordic synchronous systems.
      In the past it was a rule that at least three primary units should be running in each of the two parts of the country.
      Synchronous compensators were installed at the HVDC terminals. Since then, two additional synchronous compensators were installed in order to reduce the need for spinning primary units. I have been told that the present minimum is one spinning primary unit for each of the two parts of Denmark."

      One wonders why synchronous compensators are not used here in Ireland.

    2. Sean O'Dubhlaoigh28 October 2015 at 20:20

      In September 2009 an article was published by CEPOS , Center for Politiske Studier. It was called "the case of Denmark". It commences with the following statement "Denmark generates the equivalent of about 19% of its electricity demand with wind turbines but wind power contributes far less than 19% of the Nations electricity demand.

      The claim that Denmark derives about 20% of its electricity from wind overstates matters. Being highly intermittent , wind power has recently(2006) met as little as 5% of Denmark's annual electricity consumption with an average over the last five years of 9.7%"

      The difference between the 19% produced and 9.7% used in the domestic market being exported at close to zero prices to Norway and Sweden. With the Danish consumer subsidizing electricity consumption in in Norway and Sweden.

      To counter this claim the Danish Government asked 14 eminent academics to counter the points made in "the case of Denmark. Their main point of rebuttal being that as wind production has precedence on the grid it must output from the Combined Heat and Power Plants that is being exported. Except of course if you look at graphs of Danish Electricity production and net exchange over their large interconnector system. What you will notice here is that when wind output is high exports over the interconnector system is close to 80% the equivalent wind production. When wind production drops off imports commence. You will also notice very little variation in the outputs of their thermal plant. This may change in the future when all or most of the thermal plants close down then the secret will be out. Denmark exports over half of its wind output at close to zero prices and imports its requirements at top of the market prices. Most of the official statements about Denmark's success at wind production have as much of a base in reality as Hans Christian Andersen's fairy tales.