Author: Dr Paul Deane, Environmental Research Institute, University College Cork
Wind energy is a hot topic when it comes to discussions on Ireland’s current and future energy mix. While arguments about wind energy in the media are often distilled down to simple soundbites (where it is either the best decision or the worst decision for the country), the actual arguments for or against are a lot more nuanced and complicated... this is wind energy, the good, the bad and the policy.
The policy
The policy is often the most misrepresented part of the debate. As part of the EU 2020 Climate and Energy Package agreed in 2009, the Renewable Energy
Directive 2009/28/EC set a target for Ireland to achieve a 16 per cent minimum renewable energy share of gross energy consumption by 2020 (16 per cent RES). This covers all forms of renewable energy usage for heat, transport and electricity.
This 16 per cent target effectively combines into one mandatory target three pre-existing national targets of 40 per cent of electricity from renewables (40 per cent RES-E), 12 per cent of heat (12 per cent RES-H) and 10 per cent of road and rail transport (10 per cent RES-T) that were already in place by 2008. Our national 40 per cent RES-E target was informed by the
All Island Grid study which showed that the Irish grid could accommodate up to 40 per cent of variable renewable electricity without incurring excessive costs when compared to other generation mix portfolios.
We have seen significant recent growth in renewable energy that has been largely driven by growth in renewable electricity. However, Ireland still has a lot of ground to cover and is currently about halfway towards the overall 16 per cent RES target. Other member states on the western part of the EU are in a similar position, as shown in the figure below that shows the distance to the overall target for each member state (this is taken from analysis carried out by UCC with other EU partners in the EU
Insight-E project).
Ireland faces significant challenges in terms of renewable transport and equally renewable heat. Given that heat and transport energy collectively represent four-fifths of energy use, this means that even if we meet our national 40 per cent RES-E target we are unlikely to meet our EU binding target of 16 per cent RES as progress in renewable transport and heat are currently slow. Achieving 40 per cent RES-E by 2020 will deliver nine per cent RES.
Figure 1: Distance to overall renewable 2020 target by member state
The interaction between Ireland’s renewable energy targets and Ireland’s greenhouse gas emissions (GHG) reduction obligations are also sometimes confused. There are two key pieces of EU legislation governing GHG emissions reductions:
- Directive 2009/29/EC on the EU Emissions Trading Scheme, which encompasses emissions reduction targets in the electricity sector (and large industry). Here the obligations are imposed on individual companies at individual sites;
- Decision 406/2009/EC, the EU Effort Sharing Decision that covers emissions reductions in the transport, agriculture and heat sectors (collectively known as Non-ETS sectors). Here the obligations are imposed on member states.
This means Ireland has a legal obligation to reduce emissions in heat, transport and agriculture but no legal obligation to reduce emissions from electricity (the obligations here are placed on companies and can be met by reducing emissions or by purchasing emissions credits from another company anywhere in the EU).
Arguments that the state needs to build wind energy to meet emissions reductions targets are therefore incorrect. Building wind energy does help us meet our mandatory 16 per cent renewable energy target but does not help us meet national (non-ETS) emissions reduction targets.
There is also sometimes a perception that we are building wind energy to meet growing electricity demand. This leads to arguments that we should stop building wind capacity because sufficient existing thermal capacity exists; however, this line of thought neglects the fact that we have a binding EU target. There will be a cost if Ireland does not attain its 16 per cent RES target.
While the actual cost of not meeting the 2020 target cannot be known at this point, analysis carried out for the Department of Communications Energy and Natural Resources indicates that a shortfall in the range of one per cent to four per cent on the overall target could result in costs to the exchequer of between €140 million and €600 million.
The good and the bad
Last year wind turbines generated just over 18 per cent of our electricity in Ireland; with electricity representing about 20 per cent of energy use. Onshore wind is the most cost-effective renewable electricity generation source in Ireland costing less than €80 to generate a MWh of electricity and when additional grid infrastructure costs such as
Grid 25 and
EirGrid’s DS3 programme this could rise to €100/MWh. This is not cheap compared with today’s conventional fossil generation such as gas and coal, which can generate electricity for typically less than €55/MWh.
However the playing field for fossil and renewable generation is not level as fossil fuels do not fully pay for the damage done to the environment. In addition, globally the fossil fuel industry is hugely subsided and in Ireland we provide greater financial support for burning peat to generate electricity than we do for wind through a Public Service Obligation (PSO) levy, which is charged to all electricity customers.
The PSO levy is designed to support certain peat, gas and renewable generation plants as mandated by government and approved by the European Commission. From October 2014 domestic electricity consumers are charged a flat rate of €5.36 per month for the PSO. Peat accounts for 31 per cent of costs (€1.66 per month per residential customer bill) and renewables such as wind account for 28 per cent (€1.50 per month per residential customer bill).
The pure economic competitiveness of wind is highly dependant on gas prices. If gas prices (and carbon prices) rise, then wind energy is cost competitive, if prices stay low then gas will be the cheaper option. The question then is whether the fuel savings accrued from not burning gas to generate electricity is greater than the capital costs of wind and associated infrastructure to allow its integration into the power system.
This is a hard question to answer as it requires taking a view of gas prices over the next 10-15 years. Ireland is not well endowed with useful fossil fuel reserves and we are one of the most energy-dependant countries in the EU. Gas prices, which strongly influence electricity prices in Ireland, are subject to volatility on the global market to which we have no control over. Wind energy can act as a hedge to these spikes in higher prices.
A
recent analysis I did with colleagues in the SEAI and ESRI using a validated electricity dispatch model showed that in 2012, renewable generation averted a 26 per cent increase in fossil fuel combustion for electricity generation (valued at €297 million) and avoided an 18 per cent increase in electricity-related CO
2 emissions (2.85 MtCO
2), as compared to the simulated 2012 system without renewable generation.
Wind generated electricity averted a 20 per cent increase in fossil fuel generation and a 14 per cent increase in CO
2 emissions (2.33 MtCO
2). Each MWh of renewable electricity avoided on average 0.43 tCO
2 with wind avoiding 0.46 tCO
2/MWh. Additional renewable related balancing requirements had minor impacts on fossil fuel generation efficiency; CO
2 production rates increased by
largest thermal unit online and not wind generation. In the future, wind generation may have an impact on replacement reserve and to date there have been no detailed technical studies to investigate how the power system would be operated with levels of wind generation in excess of the 40 per cent per annum target.
Wind energy and its associated infrastructure such as pylons and overground installations can have a strong and negative visual impact. Most of the economic cost benefits analysis we undertake here and indeed in Europe neglect the cost of the impact on natural capital such as landscape aesthetics, flora and fauna etc. While visual impact is often subjective, poor planning and poor siting of wind turbines can be divisive for local communities and damaging to the progress of the energy industry in general.
Planning of large wind energy projects can be contentious and stressful for small communities where financial incentives for landowners and local community groups need to be balanced with the greater concerns and wishes of the wider community. This is a genuine challenge for Ireland and one that needs careful consideration. Community-owned wind farms and energy projects in general are not something we are familiar with in this country.
There is a strong focus in the recent green paper on energy on empowering the citizen and community engagement and it will be interesting to see what the appetite is for this type of community-owned infrastructure in Ireland.
Wind turbines do produce noise (prominently aerodynamic noise in modern turbines) and shadow flicker but this should not be an issue if the wind farm is well designed and careful location of the wind turbine in relation to dwellings is considered. Noise assessments must show that the site will not create unacceptable noise impacts.
It must be prepared in accordance with the planning guidelines and monitoring requirements and daytime/night-time compliance limits. The issue of noise can often be subjective and if you are curious about wind turbine noise then it is probably best to visit one of the many wind farms around and hear for yourself.
Wind is variable and this provides challenges for the operation of the power system, particularly at high levels of penetration. In Ireland, EirGrid is investigating these challenges through its DS3 programme and plans to increase the capacity of the system to absorb instantaneous wind penetration levels from 50 per cent today to 75 per cent by 2020. Due to our small geographical size, wind levels in different locations are strongly correlated.
The probability that all wind generation will cease for a period of time limits its ability to ensure continuity of supply and requires thermal generation. This means that wind generation generally replaces energy production rather than firm capacity. The contribution of wind generation to generation adequacy is referred to as the ‘capacity credit’ [not capacity factor] of wind and it expresses how much ‘conventional’ power can be avoided or replaced by wind power. In Ireland the 2,000 MW of wind we have installed today replaces 350 MW of conventional generation.
In conclusion, whether you are in favour of wind energy or not, there are a number of things we should all agree on: firstly we are one of the most energy-import-dependent countries in the EU and, second, we are very much exposed to the volatility of global energy markets. Irish and European commitments to reduce emissions, promote low carbon technologies and increase security of supply will require a radical change to the energy landscape in this country and in Europe.
Projections from EU analysis for the 2030 Climate and Energy Package suggest that Ireland may need to increase its renewable energy target from 16 per cent in 2020 to between 25-30 per cent by 2030 towards a steep decarbonisation trajectory to 2050; this is a far cry from where we are today at eight per cent and highlights the need for strong societal support and buy-in for all types of energy projects (electricity, heat and transport) .
This will require us as engineers to broaden our assessment of Ireland’s energy future from one that is solely based on traditional economic cost/benefits to one of a wider view that considers a longer-term approach to a low carbon future.