Associate Professor, Aalborg University

Wind Power and Pylons: Adding Facts to an Emotional Debate

Wind Power and Pylons: Adding Facts to an Emotional Debate

on May 1, 2014

The debate around wind power and pylons seems to have taken on a life of its own in Ireland in recent months. There also seems to be a lot of references to wind power and Denmark in the debate, which is very interesting to hear considering my experiences in both countries (I completed my PhD in Ireland on energy planning and I moved to Denmark in 2011 to take up my current job as an Assistant Professor in Energy Planning). Therefore, I would like to add some context to the ‘wind=pylons’ debate in Ireland, based on my experiences with both the Irish and Danish energy systems.


So what are pylons really for?

The reason we are discussing pylons in Ireland is to expand the capacity of the electricity grid. This is necessary for a number of short- and long-term reasons. In brief, a few examples I can think of are 1) electricity demand, 2) aging infrastructure 3) wind turbines, 4) new electricity demands for heating and 5) electric cars. Hence, with or without wind turbines, we will need to decide how we would like to expand our electricity grid.


Are there any alternatives to pylons?

Yes, the alternative to pylons are underground cables.


How much will the alternative cost?

Underground cables cost more to construct than overhead pylons, with this report suggesting that it is 3 times more expensive (see page 61). There is a justified argument that these additional construction costs can be counteracted by the reduced visual impact of the cables. For example, the cables can reduce property prices and tourism to an area. However, these are difficult costs to quantify and I am not aware any study that has done so.


Is it possible to develop wind power without pylons?

Yes. Wind power is not directly connected to overhead pylons. Denmark has the world’s largest percentage of wind power and the plan in Denmark is to underground its electricity grid using cables.

Denmark is planning to underground 75% of its electricity grid in the future, see page 16 of this report and look under the headings “track” in table 5.1.1., while the other aim in Denmark is to have 50% wind power for electricity production by 2020. To put this in context, the aim in Ireland is to have 40% wind power in 2020. This means that under existing plans, Denmark will have more wind power with underground cables in 2020, than Ireland will have with overhead pylons.


How much will it cost to develop underground cables?

Although the construction price of cables is more than pylons, the relative cost of cables is low compared to the rest of the electricity sector. For example, the price to use cables for 75% of the electricity grid in Denmark is ~€2 billion in total. These cables typically last 40 years, so in annual terms you could say that these cables cost ~€50 million/year. In comparison, we spend more than €2000 million/year on producing electricity in Ireland. Therefore, undergrounding the cables represents a relatively low percentage of the total costs to generate electricity (~2-3%).


How much does wind power cost?

Wind power in Ireland is cheap. Onshore wind turbines in Ireland can produce electricity cheaper than any other type of power plant. This is due to the very windy conditions in Ireland (Detailed calculations on this are available in a report I just published here, see Figure 1). The key challenge for wind power is the high initial investment cost. This means that investors currently need incentives to build wind turbines due to the risk of paying all of the investment costs up-front. Furthermore, people in rural areas can benefit the most from the development of wind power, which is concerning since this seems to be the source of most protests at present. This suggests that there is a severe communication issue in relation to Ireland’s energy policy at present.


What are the benefits of pylons?

Pylons are cheaper to construct and they are a well-established technology.


What are the benefits of cables?

The clear benefit of underground cables is that it can eliminate the visual impact of expanding the electricity grid. This is a key benefit for everyone in Ireland.

Those living near the cables clearly believe that the visual impact of pylons can devalue their land and property, and the exposure to high voltage lines can cause health problems (which is something I am not qualified to comment on). In any case, due to these concerns, there are often local protests against pylons, as we have seen in Ireland recently, which cause delays and increased planning costs.


Should we use pylons or cables?

If you value construction cost alone, then pylons are a better option. However, if you would prefer to eliminate the impacts of pylons for the extra construction costs I have highlighted earlier, then cables are for you. I believe that this is the type of factual debate we need in Ireland about how to expand our electricity grid in the future.


Personally, I am happy that the Danish Government is spending a little extra of my tax money on underground cables instead of overhead pylons.