1 Pumped-storage hydro
Six years ago a simple idea was proposed by a Dublin-based scientist, one that, on paper at least, would leave Ireland awash with clean, zero-carbon electricity. It promised to make us major exporters of power, sending current into Britain via the existing two subsea interconnectors to Wales and Scotland.
It was based on an old and well-known technology called pumped-storage hydroelectricity. This plan involved building artificial seawater lakes, 200m or more above sea level, off our western seaboard. They would be filled using pumps powered by wind turbines.
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These large lakes could then generate hydroelectric power by letting the lake water flow down through a pipe to spin the generators.
The highest energy peak yet to occur on our national grid topped out at just over five billion watts of electricity (5GW). A single lake covering, say, two square kilometres had the potential to produce 100GW of electricity, more than we would use over 20 years.
Prof Igor Shvets, professor of applied physics at Trinity College Dublin, proposed the idea in a talk in 2008 called The Energy Options for Ireland.
“It was just at the start of the financial crisis,” Shvets says. “The macroeconomic environment was not appropriate at that time and not at that scale.” Building such a plant could have cost €1 billion.
Supporters set up a foundation and a website, Spirit of Ireland. The ESB and the government were lobbied to consider the option, but things did not progress.
“We failed to raise the necessary funding,” says Shvets. “It closed a couple of years ago. The idea is great, and the problem was definitely not the technical issues.”
He believes that it is only a matter of time before the idea takes hold. All of the technology needed to build and run such a plant already exists. The ESB itself runs one at Turlough Hill, Co Wicklow.
Shvets identified 30 locations where such a plant or even larger ones could be built, high enough above sea level.
The high initial capital costs may work against any proposal to start such a project, yet in time this method may represent a way in which Ireland could achieve a high degree of energy independence.
2 Nuclear energy
It seems improbable that Ireland would ever embrace nuclear power, given the strength of feeling against this option. Public opposition helped to end talk of a nuclear station at Carnsore Point, in Co Wexford, back in the 1970s, a time when the government was considering four plants to meet Ireland’s needs.
It has remained off the agenda since, with ready arguments against it, not least safety. Chernobyl, in 1986, and the Fukushima disaster, in 2011, when Japanese nuclear plants were damaged by an earthquake and tsunami, provide ample evidence that when things go wrong with nuclear power they go seriously wrong.
Even if safety could be assured, other aspects are working against it. There is the multibillion-euro construction cost, the requirement to spend almost as much for decommissioning, and the need to keep safe thousands of tonnes of liquid and solid radioactive waste for at least 250,000 years.
If these costs and technological challenges could be put aside, nuclear does offer advantages. Once running, plants produce inexpensive, dependable power, and they can do so for years. They also release far less greenhouse gas than, say, a coal-fired power plant such as Moneypoint, in Co Clare.
But lifetime costs, waste storage and safety risks cannot be put aside, and these will always combine to make nuclear a nonstarter in Ireland.
3 Offshore fossil
Ireland has been in the offshore-energy business for a long time. Our biggest commercial find, the Kinsale Head gas field, off Co Cork, was discovered in 1973. The Corrib gas field, 80km off Erris Head, in Co Mayo, which has yet to deliver gas into the national grid, was found in the mid 1990s. We also have proven flows of oil from the Barryroe oil fields, off the south coast.
Based on existing discoveries, the amounts of oil and gas available to us will not make Ireland rich in the foreseeable future. Corrib was a welcome discovery, but recoverable reserves are only about 70 per cent of the Kinsale field. And it will be difficult to make Barryroe worth the high cost of development, given that the value of crude oil has halved over the past few months.
The oil flows from test wells in the Barryroe field touched 3,500 barrels a day, but there would have to be many wells delivering at this output to justify investment in production when oil prices have fallen so low.
There is always the possibility of some big offshore discovery, but drilling activity off our coasts has been limited in recent years. We cannot count on an unexpected offshore bonanza to help power Ireland in the short to medium term.
4 Fracking
Hydraulic fracturing, aka fracking, has produced an energy gold rush in many countries, with the assumption that everyone has shale rocks bearing natural gas under their feet. The US has become a net energy exporter again because of fracking, but there will be no rush to pursue it on this island.
The method pumps fluids into shale deposits at high pressure to shatter the rock and release the gas. It works, but there are questions about the environmental risks and long-term damage where fracking has occurred.
An Australian company, Tamboran Resources, has sought planning for test boreholes and permits to frack along both sides of the Border, in Fermanagh, Cavan and Monaghan. So far the applications have all been rebuffed.
Mindful of growing public concerns, the previous minister for energy, Pat Rabbitte, imposed a moratorium on any permits until the Environmental Protection Agency could conduct a two-year study into the effects. This is due in 2016.
Northern Ireland has taken a similarly conservative approach. Its minister for energy, Mark Durkan, has said that any permissions related to fracking would be granted only in the presence of “strong evidence” that it is safe to the public and the environment.
Yet if in the future other energy sources were to become difficult to obtain, fracking could provide a useful energy supply. Industry sources believe that between 10 trillion and 20 trillion cubic feet of gas could be trapped in our shales, although no data is available to prove this.
5 Microsupplies
One version of our energy future anticipates us all becoming energy producers, even to the point of selling power back into the grid. The idea, based largely on current technology, involves linking up our houses and cars with the national grid via a “smart” system able to monitor energy use.
We would have our own small windmill churning in the back yard and solar panels on the roof. These would be used to charge batteries for light and heat in the house and also the battery in the electric family car. The smart technology connecting us to the national system would monitor these energy sources and divert excess power into the grid, with payment due at an agreed rate.
Electricity would flow in the other direction on windless days and at night, if the car and house batteries did not have sufficient capacity to keep the house lit and warm.
Day or night, if you didn’t plan to use the car, you could also sell its stored power into the grid at any time and help defray your electricity bill. Doing this is predicated on that essential smart system; research groups in Ireland are developing systems to make this happen.
6 Wind
Wind energy has proved highly successful in Ireland – not surprising, given that we sit on the edge of the north Atlantic. Its deployment also continues to grow apace because it can help us meet EU directives on renewable energy, which require that 20 per cent of our total energy needs come from renewables by 2020.
Installed wind capacity – maximum capacity that a system is designed to run at – now stands at 2,263 million watts (MW), spread across 188 wind farms, according to the Irish Wind Energy Association. The installed capacity has the ability to deliver almost half the country's electricity requirement, but to meet EU targets we would have to install another 2,000 MW capacity.
Costs are mainly associated with building the turbines; the electricity they produce is provided at almost zero cost. The turbines don’t create waste streams and are low-maintenance. This means that wind delivers the lowest-cost electricity on offer to the electricity suppliers.
Offshore wind power is more expensive, given the much higher costs of building and maintaining the turbines in an extremely harsh environment. But it does not run into public opposition as plans for land-based turbines do. Wind will play an increasingly important role in supplying energy as we move towards the goal of a carbon-neutral energy system by 2050.
7 Energy efficiency and conservation
One of the best ways to reduce the cost of energy is to not use it in the first place. For this reason, “energy efficiency first” is the mantra at the Sustainable Energy Authority of Ireland. You release no carbon and you save money by not using it, either by increasing efficiency or by pulling out a few plugs.
This used to come down to switching something off, but technology has helped us use less energy. How far you can go with this depends on the energy sector involved. Technology exists to reduce the energy input into homes to near zero. Good design and new materials mean homes are 30 per cent more efficient than they were 20 years ago. LED lighting uses only a tenth of the power of conventional lighting.
Information and computing technology is making a difference in reducing energy costs. Smartphones can control home heating and lighting remotely. A simple phone app makes it easier than ever to avoid missing the next bus, making public transport work better for the individual as well as saving motor fuel.
More advanced systems are being developed through the “internet of things”. Your heating and even refrigerator can be switched off for a time if electricity wholesale prices go up, saving you power and money.
8 Wave energy
The wave energy crashing against our Atlantic seaboard could deliver enough electricity to power all of continental Europe – if we could capture it. Think then of the abundance available if we could capture enough just to meet our own national demand.
Engineers and research scientists have worked for years to develop cost-effective wave-energy systems, and there are working wave farms in Portugal and Scotland, for example. It is a technology that has yet to mature, however.
It requires that you build something that can not only convert the movement of water into electrical power but also be able to survive in the tough offshore environment. The bigger you build it the more it costs, as well as the more difficult it becomes to keep it in place without getting damaged or even ripped free.
This has not deterred research, and a number of Irish universities have active programmes in . Energy commentators suggest that it may take 20 years before designs are available that can deliver enough power to make them pay their way. Until that time we have to rely on less demanding renewable resources.
9 Tidal energy
Tidal electricity generation is not the same as wave. The turbines are turned not by waves flushing over the hardware but by the slow movement of large volumes of water. It certainly is a dependable source of energy, as we know that the tides will ebb and flow twice a day every day.
The downside: because the system does not rely on the energy-rich violence of crashing waves, there are far fewer places where tidal energy can be produced economically.
The best places are where a lot of tidal water is flowing back and forth. In Strangford Lough, Co Down, for example, a company named Sea Generation installed a 1.2MW tidal-energy unit in 2008. And OpenHydro, based in Dublin and Greenore, Co Louth, has a number of international projects under way using seafloor-mounted units.
We have nothing like the Bay of Fundy around our coastline. This bay in Nova Scotia sees tidal rises of 14.5m, which amounts to a lot of water.
Like wave, this technology needs further research and deployment to confirm that it is possible to make it pay, or at least serve as a backup to enhance security of supply.
