Ireland must have 40% renewable energy by 2020. But where will the rest come from? Barry O'Halloranreports
THE WIND looks set to play as pivotal a role in determining what we pay for electricity in 10 years time as oil prices now do. Because of the approach we are taking to meeting greenhouse gas reduction targets agreed by the EU, Ireland is bound on a path that will see 40 per cent of electricity generated from renewable sources by 2020.
Dermot Byrne, chief executive of Eirgrid, the agency that runs the island’s two electricity transmission networks – and is thus responsible for security of supply – says the 40 per cent target is achievable. What happens after that is becoming more important.
In the decade succeeding that date, some of our biggest power plants, including Moneypoint in Co Clare, which can generate up to 900 megawatts (MW) of electricity, enough to power 900,000 homes, and Kilroot near Carrickfergus, which produces over 500 MW, are set to close. They will have reached the end of their useful lives. Both were built in the 1980s and electricity plants have a 25- to 40-year lifespan.
Added to that, burning peat to produce electricity will no longer be an option at that point, for various reasons, some linked to cutting emissions, others to EU measures aimed at preserving the peat bogs themselves.
Eirgrid this week published a report, Low carbon generation options for the all-island market, exploring options for generating electricity. The document, researched and written by European consultancy, Pöyry, takes as its starting point the idea that the 40 per cent renewable energy target will have been reached.
Byrne says the report is designed to look at the options available to the Irish system, and is a step towards building a consensus around how it might be developed.
One factor it has to take into account is the long-term aim of making power generation “carbon-neutral” – meaning zero greenhouse gas emissions – by 2050. The point at which the final transition to this will begin is 2035.
However, that has to be balanced against ensuring that we have enough electricity and that the generators and suppliers get a return for their investment.
It runs the rule over a number of scenarios, which include options such as natural gas, nuclear power, coal burning and carbon storage, a system with up to 80 per cent of power coming from renewables, and increased levels of interconnection with Britain and possibly France.
The report’s author, Dr Phil Hare, points out that as 40 per cent of electricity is going to come from renewables – for which you can read wind – the wind is going to play a “significant” role in what we pay for electricity. The wind blows at the right speeds for power generation roughly one-third of the time on average. This not only varies from day to day, but from year to year, by 25 per cent.
As wind will have to be backed up by natural gas and/or interconnection, this means on low-wind years, the extra fuel costs could run to as much as €200 million, which will in turn have an impact on electricity prices. The opposite will also apply, as high-wind years will cut down on the need for imported fuel.
Both Hare and Byrne are reasonably sceptical about the idea that harnessing Ireland’s wind resources could position us to become a large-scale exporter of electricity.
This theory is based on the idea that if the wind is blowing at the right speed during periods of low demand, the extra electricity can be sold abroad via interconnectors to Britain and elsewhere.
Hare says as Ireland and its nearest export customer for electricity, Britain, occupy a comparatively small geographical area, the wind is also likely to be blowing at suitable speeds there, and Britain is developing its own wind farms.
A key issue is that Eirgrid is looking for low-carbon options, and ultimately no-carbon options.
The system still produces a lot of greenhouse gas. Pöyry says that in 2008, it was 500g per kilowatt hour (kWh). This means that if you leave a 100 watt light bulb on for one hour, it will produce 50g of greenhouse gas. The aim is to cut this to 10g by 2035, an 80 per cent reduction.
The report takes six different options, three with a near-80 per cent renewable energy component. In two cases, it is backed up, one by interconnection with other countries, the other with pumped storage, which involves using spare electricity in periods of low demand to pump water to reservoirs, which is then released and used to drive generator turbines when power is needed. However, this technology is not yet developed enough to provide the back-up required.
The other scenarios are systems with 40 per cent renewables, combined with either gas, nuclear or coal-fired generators; and carbon capture and storage, which involves capturing the carbon released by burning coal and storing it, possibly in disused oil wells or similar underground structures. The technology for doing this is still being developed, and Pöyry does not expect it to be commercial until at least 2018.
According to Byrne, the nuclear option, even though it would guarantee low greenhouse gas emissions, faces a number of issues, not least that it is illegal under Irish law to build a nuclear plant.
Even after changing this law, the Government would still have to win public acceptance for such a plan.
Also as the technology stands, a nuclear plant would have to have a capacity of at least 1,600MW, which is around four times the size of the average Irish power plant, and would be too large for the overall system.
However, Pöyry says as technology advances, smaller plants could be possible, while demand could rise.
When the capital investment, fuel prices and the system operating costs are taken together, the gas, nuclear and coal-fired options all cost between €4 billion and €5 billion a year, while the renewable-based options are more expensive, topping €5 billion a year.
Pöyry explains it is because the renewable options are likely to cost more to build and would require more investment in the the network.
However as variable costs such as fuel are lower, this helps to balance it out.
