Author: Dr Paul Deane, Environment Research Institute, University College Cork On Christmas Day last year, as people were sitting down to dinner, a high-pressure weather system was slowly moving over Ireland, causing temperatures to drop and wind speeds to reduce to an almost calm. Over half a million households were heating their homes with natural gas, while the electricity system called on gas-fired power plants and electricity imports from the UK to meet the bulk of demand in the absence of any wind generation. Some 150 GWh of natural gas was transported from the UK through the Moffat Interconnection point into Ireland to meet our energy needs on that day. While there is nothing special or significant about this quantity of gas, it does provide a snapshot of challenges faced by Ireland and other EU member states as we transition to low-carbon energy systems with high levels of intermittent renewables. The key questions are: what will provide back up to intermittent renewable generation and from where will this come? Gas is now seen as an important transitional fuel, which will enable economies to evolve towards a low-carbon future. Gas is a flexible fuel that can be used for transport, heating and electricity generation with lower associated emissions than other fossil fuels. Renewable gas can also be produced and pumped into the gas grid. Ireland and Europe are similar in many regards in relation to gas, with both being both major consumers and major importers of gas. Ireland imports 95% of gas used and gas represents about 30% of energy supply. This year, Ireland will see the introduction of gas from the Corrib gas field and this will ease our gas import dependency over the next decade. Europe’s reliance on natural gas – and, in particular on Russian gas – has been well exposed and reported in the past year. Europe imports about a third of its gas from Russia, with the remainder coming from Norway, LNG (liquefied natural gas) imports and North Africa. While the current political situation in Ukraine had no observable impact on import levels from Russia into the EU, it did provide a wake-up call for EU member states to reassess the strong import dependency the EU has on Russia. After negotiations last autumn, a $4.6 billion package brokered by the European Commission was agreed by Russia and Ukraine to secure gas for Ukraine and ultimately also for Europe. Russian deliveries to Ukraine were resumed in December 2014, following six months of disruption. A series of stress tests undertaken by the European Commission and ENTSO-G last year showed that minimising supply cuts during a possible serious gas supply disruption can best be achieved by broad co-operation and proportionate and effective national security of supply measures. There are, however, significant differences in the levels of exposure to gas interruption from Russia, with the Baltics, Finland and south-east-European member states being the most affected countries.

Gas prices and energy modelling

There certainly are no cheap or easy options to Europe’s dependency on Russian gas. EU modelling has shown that gas will remain an important vector in the energy system in Europe out to 2050, where it may meet a quarter of energy needs. In the short term, the EU needs to focus on mechanisms for moving gas more efficiently around Europe, particularly form west to east. Strong progress has recently been made on improving physical bi-directional gas flows on a number of existing cross-border pipelines. As of 2014, some 40% of all 53 cross-border interconnection points in the EU are bidirectional, up from 25% in 2009. Increasing LNG imports is the other option open to the EU to reduce dependence on Russian gas: recent years have seen a steady shift in gas imports away from LNG and towards pipeline imports, driven by high LNG prices supported by booming demand for LNG in Asia and Latin America. However, Asian spot LNG prices have gone down considerably this past eight months, as a result of mild weather and high stock levels. It can be expected that the recent plummeting of global oil prices will also pass through oil-indexed gas deliveries – both LNG and pipeline – in the coming months, which may result in further falls in the price of gas in the EU. Such a situation could be of benefit to the EU and contribute to narrowing the price gap between pipeline and LNG imports. However, gas flows and prices are strong influenced by weather and geopolitics, which are both notoriously challenging to predict. In the short term, Europe is set to remain reliant on Russian gas. While oil is the dominant source of energy in Ireland, accounting for 47% of total primary energy, natural gas accounts for 29% of total primary energy and provides an important backbone to the electricity sector, where just under half of electricity is generated from natural gas. Research undertaken in University College Cork with the Irish TIMES Integrated Energy Systems model of Ireland shows that gas will play a pivotal role in Ireland’s transition to a cost efficient, low-carbon economy in 2050. This research is funded by the Environmental Protection Ageney and the Sustainable Energy Authority of Ireland This total system approach to energy modelling is unique, as traditionally energy planning has looked at single sectors of the economy in isolation (for example: wind and electricity). This has limitations and is somewhat like trying to solve a Rubik’s cube by looking at one face only. Integrated energy-system modelling, on the other hand, allows all dimensions of the problem to be analysed to determine least-cost pathways to achieve emissions reduction from a full-systems perspective. This allows the interactions and dynamics of different energy and technology choices to be scrutinised and analysed from a holistic viewpoint. This is especially important for gas due to its ability to be used in transport, heat and electricity and for addressing issues surrounding land competition and biogas. [caption id="attachment_18309" align="aligncenter" width="948"]Natural-gas-Ireland Figure 1: 2050 Sankey of Irelands Energy System in Low Carbon Future (Source: UCC)[/caption] The results shown in Figure 1 from the Irish TIMES model for a low emissions scenario to 2050 show that natural gas will continue to play an important role in electricity generation, particularly post 2030, if carbon capture and storage technology is available. Gas will also continue to play an import role in other sectors. The residential sector will see a decrease in demand per dwelling for gas due to energy efficiency improvement in the housing stock, but an overall increase in demand for gas will occur as more customers switch from oil to gas for heating. In Ireland it is estimated that over 100,000 dwellings are within 20m of the gas grid.

Projected increase in renewable gas and other energies

Renewable gas is also expected to play an important role, particularly in the transport sector. While much has been speculated about Ireland’s offshore natural gas resource, the renewable gas resource has been more firmly quantified. Research by Prof Jerry Murphy in University College Cork has investigated renewable gas from biological, thermal and electrical sources. His group has shown that that co-digestion of slurry from dairy cows in Ireland with grass silage quantities equivalent to 1.1% of grassland would provide over 10% of energy supply in transport. Exciting research is also ongoing in the use of seaweed and algae, both of which Ireland has in abundance. Renewable gas may also be produced through thermal gasification of woody crops such as indigenous willow or imported wood-chip. Power-to-gas is a storage mechanism whereby surplus variable electricity may be converted to gas at times when high production of electricity corresponds with low demand. While these technologies are not deployable at market stage today, focussed research and development will help bring costs down. Strong synergies and multiple socio-economic benefits exist between renewable gas and agriculture in Ireland and greater co-operation between these sectors is required to leverage this opportunity. Security of supply remains an outstanding issue with gas; it is unlikely that a shale gas revolution (similar to what has happened in the US) will happen in Europe. Europe and Ireland are set to remain importers of fossil fuels out to 2050. Energy efficiency and increased deployment of cost-effective renewables will help reduce the need for gas and mitigate energy security issues. Energy systems modelling research in UCC shows, however, that a least-cost low-carbon energy system comprises significant levels of biomass and biofuels, which have their own energy security concerns. Further analysis shows that relying solely on indigenous resources is technically feasible, but an Irish energy system that is 100% energy independent comes at a cost that is many orders of magnitude higher than optimal. The challenge for Ireland is to navigate a pathway to a low-carbon future where systems costs, energy security and GHG emissions are balanced in a manner that is right for Ireland.