Total greenhouse gas emissions in Ireland are only a little ahead of 1990 levels, despite population growth and economic expansion in the interim, but they can be further contained. The European Union countries have been to the fore worldwide in addressing the imperative of emission reduction and Ireland should certainly seek further opportunities to cut emissions.

But Irish policy has become excessively reliant on the subsidisation of renewable electricity generation and a new report from the lobby group Wind Aware released on Wednesday argues that the costs, not all of them fully visible, have become excessive. Ireland has enough windmills, in a nutshell, and more promising routes to emission reduction lie elsewhere.

Transport and energy not the only sources of emissions

The public tends to associate carbon emissions mainly with car use and with electricity consumption. The transport and energy sectors do indeed produce substantial emissions but more come from industry, agriculture and buildings, including the residential sector. Electricity generation accounts for about 19% of greenhouse gas emissions in Ireland and the total for the sector has fallen over the last two decades despite a rise in electricity consumption.

The reason is extra renewables, like wind, which have negligible emissions, and the replacement of high-emission fuels with natural gas, which emits only about half, per unit of power produced, the emissions from peat, oil or coal stations.

Electricity requirement

Wind farms have recently been contributing about one-quarter of Ireland’s electricity requirement, a high figure by international standards. The problem is that this contribution has become very costly and there is a risk that any attempt to further increase the share from wind, or from other intermittent technologies such as solar, will add more and more cost, for less and less in emission reduction.

Bear in mind that 81% of emissions come from sectors other than power generation

There is a rational ceiling on the amount of renewable electricity generation to aim for and Ireland is already at, or very close, to the ceiling. Bear in mind that 81% of emissions come from sectors other than power generation. There may be cheaper opportunities to cut emissions in these sectors which go a-begging if there is an excessive focus on wind.

The Wind Aware report attempts to catalogue the full range of costs imposed on the Irish energy sector by the current reliance on wind technology. There has been no comprehensive official study of these costs, a remarkable state of affairs.

Some organisations such as EirGrid, the Sustainable Energy authority, the Commission for Energy Regulation or the Department of Energy itself should long ago have undertaken these calculations. Electricity has become relatively more costly in Ireland than in many competitor countries and the high costs of wind power are a large part of the explanation.

Guaranteed price

Wind farm operators are paid a guaranteed price, in excess of the wholesale market price for electricity, the so-called feed-in tariff. The cost of this subsidy is not paid for out of Exchequer funds but is added to electricity bills. It is currently costing about €300m per annum, despite the insistence of the wind-power industry that its technology is a low-cost option.

Since wind farms are dispersed to hundreds of locations, many of them remote from the centres of high demand, there are additional costs for grid expansion and maintenance. These costs are hidden, added to the use-of-system charge and buried in consumers’ bills. The Wind Aware report estimates that they exceed €200m annualised.

There are other hidden costs. Since wind power is unpredictable and intermittent, adequate capacity from conventional stations must be available to avoid blackouts. The cost of capacity payments to generators adds further expense in the hundreds of millions.

Ireland’s installed fleet of wind farms is now so large that some of its output must, at times of plentiful wind, be curtailed. In 2015, a total of €21m was paid to wind farms, which could not be permitted to generate. Wind farm construction continues apace and the frequency of curtailment can be expected to rise.

Intermittent

Since wind power is intermittent, the conventional power stations, particularly the gas-fired units, are operated sporadically, ramping up and down in response to the variations in wind farm output. This imposes hidden costs as well as hidden carbon emissions.

These gas units were not designed for intermittent usage and their useful lives will be impaired. In addition, they are not fully fuel-efficient unless operated continuously, so the sporadic patterns of generation imposed upon them involve higher per-unit carbon emissions.

The direct subsidy of €300m per annum to wind farms is, according to Wind Aware, only about one-quarter of the total costs

The direct subsidy of €300m per annum to wind farms is, according to Wind Aware, only about one-quarter of the total costs. The wind fleet does indeed reduce Ireland’s carbon emissions, perhaps by about 3% or 4% of the national total from all sources. The issue raised by this report is whether less costly pathways to emission reduction are available. It should not have been left to this voluntary group to raise these vital policy questions.

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