Emissions Reductions: One Key Sector That’s Already On Track

Ireland is behind on reducing emissions. However, one key sector of our economy is already right on track to with decarbonising: Electricity generation. But can we reach even higher targets for variable renewable power by 2030? To answer this question, we first need to understand our current electricity generation mix:

Ireland’s Electricity Generation Mix for 2019:

Ireland's electricity generation mix for 2019:Source, Contribution (%)
Natural Gas,50.8
Wind,32
Peat,6.1
Hydro,2.8
Other Renewables,2.7
Electricity Imports,2.1
Coal,1.6
Waste,0.9
Oil,0.9
Solar,0.07

Ireland’s Electricity Generation Mix for 2019. Data source: SEAI Energy in Ireland 2020 Report. Image License: CC-BY. Credit: energyd.ie

The chart shows that in 2019, gas (51%) was the biggest source of power, followed by wind (32%). There’s an interesting story to tell about each fuel source, so let’s dig a little deeper.

Coal: 2%

Coal was once a dominant source of power. Nowadays though, natural gas and renewables beat coal on price. Another problem is that you can’t easily ramp coal plants up and down to match demand. Because of these issues, coal provided only 1.6% of our power in 2019. In fact, the outlook for coal is so bad that the ESB had to write off it’s only coal power plant as a worthless asset. Coal just can’t compete on price. Coal is on the way out.

Peat: 6%

Turf-powered electricity is both polluting and expensive. However, the Irish government wants to prevent job losses so they’ve decided to prop up the turf-burning industry with subsidies. You pay to keep Ireland’s final turf-burning power plant open with a levy on your electricity bill.

Two out of Ireland’s three turf-burning power plants closed at the end of 2020 due to An Bord Pleanála’s refusal to grant them planning permission renewal. This means that we will be getting less than 3% of our electricity from this turf in 2021. Looking further ahead, the final turf-burning power plant (Edenderry) has planning permission to burn a mixture of 60% peat and 40% biomass until 2023. The owners of the plant have also applied for planning permission to run it on 100% biomass from 2024 until 2030.

Gas: 52%

Natural gas has two major advantages. Firstly, you can easily throttle gas plants to match demand. Secondly, natural gas is cost-effective. These factors made gas the dominant power source in Ireland for 2018. Unfortunately though, relying too much on gas brings problems:

Problem #1: Supply Insecurity

Insecure gas supply is major problem for Ireland. In 2016 we got nearly 70% of our gas from indigenous sources including the Kinsale and Corrib gas fields. However, these gas fields are running out; each year we’re more and more dependent on imports. Worse still, all the pipelines that supply Ireland with gas come from Britain. This means we’re basically buggered if Britain ever decides to turn off the tap. One possible solution to this problem is to build an import terminal for liquefied gas (LNG) in the Shannon Estuary. The USA is very keen on this idea because it would let them take a share of the European gas market from Russia. Similarly, the European Union is keen to have a more diverse gas supply. However, an LNG terminal won’t solve the second problem with gas:

Problem #2: Greenhouse Gas Emissions

Gas burns cleaner than coal, but it still produces CO2. On top of this, natural gas itself is a potent greenhouse gas. This means that leaks during production and transport are a significant problem for the environment. No surprise then that the Green Party wants to stop the new gas import terminal. Overall, it looks like gas usage is set to decline.

Renewables: 33%

Renewable electricity is booming in Ireland. In 2005, we got only 7% of our electricity from renewable sources. By 2018, that number reached 33%. And Eirgrid are confident we’ll get 40% of our electricity from renewables in 2020. Pretty much all of this growth has come from onshore wind:

The Decade of Onshore Wind

A scheme called “REFIT” is responsible for Ireland’s wind power boom. Under REFIT, wind farms get a guaranteed price for the power that they produce (€0.08 per unit in 2019). This gives investors a stable income, making it much easier for them to secure loans to build their wind farms. You pay for the REFIT scheme with a levy on your electricity bill. REFIT closed in 2020 and will be replaced with renewable energy auctions:

Renewable Energy Auctions

In a renewable energy auction, companies compete for electricity supply contracts. The company with the lowest price wins. In theory, this provides the best possible deal for electricity consumers.

Ireland’s first renewable energy auction was in the summer of 2020. Onshore wind energy won 66% of the energy contracts while solar won 34%, according to provisional results from Eirgrid. However, upcoming auction rounds are likely to include much more offshore wind.

Offshore Wind

The Arklow Bank Wind Park is Ireland’s first and only offshore wind farm. It was built in 2004 and has a capacity of 25MW. By today’s standards that’s tiny. However, offshore wind may play a much bigger role in the future due to some significant advantages. First of all, offshore wind turbines are out of the way. Secondly, the best sites for offshore wind turbines are in the Irish sea, close to the densely populated East coast. This helps because you save a lot of money on transmission when you generate power close to where it’s needed.

The cost of offshore wind has dropped dramatically. For example, offshore wind farms in Britain and the Netherlands are now producing power at or below market prices. The Irish government are naturally keen to get in on this action, and they have set a target of 5 GW of offshore wind capacity by 2030. For conext, 5GW of offshore is enough to provide roughly 40% of our current electricity needs. Expect lots of auctions over the next few years.

Offshore wind farm on a cloudy day with waves.
Offshore wind farms benefit from windy open-sea conditions

Utility-Scale Solar

Ireland’s first utility-scale solar farms will soon be built, following the 2020 renewable energy auction results. Overall, the solar farms awarded capacity in that auction will be sufficient to provide around 2% of Ireland’s electricity supply. Over the coming years, utility solar’s share could increase significantly. However, with a n Irish capacity factor of around 10%, versus around 35% for wind, it’s hard to see solar overtaking wind as Ireland’s main electricity generation source.

Rooftop Solar

The place where solar will really shine (get it?) is on rooftops. Perhaps you’ve been thinking “€0.08 for wind power in Ireland! Why is my electricity supplier charging me €0.18 a unit?!” The main reason is that generation costs are only part of what you pay for electricity. Other things, like transmission costs and taxes, add much more to your bill. With rooftop solar you don’t pay anything for transmission. That’s why rooftop solar for homes and businesses will be popular over the coming years.

Nuclear Will Never be Viable

Every few years the nuclear debate resurfaces and the discussion always seems to revolve around safety. Advocates point out that nuclear power has the best safety record of all power generation methods. On the other side, opponents cite terrifying accidents and radioactive waste. However, the big problem with nuclear power in 2020 has nothing to do with safety. In fact, it’s the much more mundane question of cost:

New nuclear power plants are stupidly expensive. Take for example the new Hinkley Point C power plant in England. The project is already £2.9 billion over budget and behind schedule. When it’s finally complete, electricity buyers will be forced to pay the ludicrous price of £0.09250 for every unit of electricity the plant produces. That’s more than twice what offshore wind costs in Britain. Ultimately, electricity consumers will have to foot the bill.

“Next generation” nuclear technologies like thorium reactors and nuclear fusion won’t make much difference. This is because there’s much more to nuclear power plants than just reactors. Do you think those giant cooling towers come cheap? The real “nuclear waste” is the billions of extra pounds that UK consumers will have to pay for their electricity because of new nuclear plants. Let’s not make the same mistake in Ireland.

Cooling towers and containment dome at a nuclear power plant.
Even leaving the cost of the reactor aside, other components like these huge cooling towers make new nuclear power plants uneconomic. Image Credit: Mingo123 on Pixabay

Balancing Supply and Demand

Balancing supply and demand is already a challenge for grid operators. Adding more renewables to the mix will only increase the challenge. Let’s first look at how the Irish grid balances supply today. Then we can consider what technologies to use over the coming years. For context, electricity demand ranges from roughly 3000MW at night to roughly 5000MW during the day.

Interconnectors

The East-West Interconnector links Ireland and Britain by sub-sea cable. This allows us to import or export up to 500MW of power at any time. At present we don’t have any other interconnectors. However, coming up this decade is a new 700MW interconector from Ireland to France. This will help balance electricity supply by linking us to the giant “Synchronous Grid of Continental Europe”.

Pumped Hydro Stations

Pumped hydro stations store energy by pumping water uphill. Later, when demand is high, the water flows back down to generate power. Currently, Ireland’s only pumped hydro station, Turlough Hill, provides up to 292MW of power. However, there’s a proposal to build a second pumped-storage unit in Silvermines, Co Tipperary. The project should have a peak power output of around 360MW and 1780MWh of storage capacity.

On the other hand, the project might struggle to compete with the falling costs of grid-scale battery storage. With an anticipated price of around €650 million, the project would have a price per megawatt hour of storage around €365. Therefore, it may soon struggle to compete with battery storage which has already seen costs drop to €434 per megawatt hour with prices continuing to fall rapidly (calculated from this article).

Grid-Scale Batteries

Grid-scale batteries have gotten much cheaper lately. Because of this, the technology is now booming in many parts of the world. With at least 200MW in the pipeline, battery storage will soon play a significant role in the stability of Ireland’s grid, too. A new opportunity for battery storage comes from the growth of electric vehicles. The plan is to use electric car batteries for grid backup while the cars not being driven. In this way, a pool of a few thousand electric car batteries could provide a substantial electricity reserve.

Demand Side

Another solution is to simply use more power when it’s available. Day/night metering is one way to encourage people to shift their power use to off-peak times. Likewise, the Irish grid operator pays factories to use less electricity when the supply is short.

Smart meters bring new opportunities for demand-side management, like time-of-use metering. Taking this a step further, your electricity price could be linked to the wholesale market rate. For example, electricity users might pay less on windy days and more on calm days. Tactics like these can lead to lower electricity costs overall.

Power-to-Gas

Power-to-Gas involves producing hydrogen with surplus electricity. This hydrogen can then be blended into the gas supply or used in industry. Power to gas technology is growing in Germany and could reach Ireland soon. The technology could make a lot of sense along Ireland’s Atlantic coastline, where surplus power is often curtailed.

Conclusion

Wind power will soon be our main source of electricity while gas will be the back-up for when the wind isn’t blowing. In the longer term we’ll reduce our gas usage. To achieve this, we’ll need more storage and interconnection. We’ll need to use many different technologies to reach 70% renewable electricity by 2030.

Ireland’s Electricity Generation Mix in 2031. Author’s Prediction:

Pie chart showing the author's prediction for Ireland's power generation mix in 2030.  Same data as the image caption.
Hydroelectricity 2.5% Onshore Wind 55.0% Offshore Wind 12.5%
Small-Scale Solar 5.0% Utility-Scale Solar 2.5% Natural Gas 22.5%
Image License: CC-BY. Credit: energyd.ie

What do YOU Think?

Will we meet our 70% renewable electricity target for 2030? What will our electricity generation mix be by then? I challenge you to make your own prediction. Post it in the comments!