Presentation of Teagasc Director Professor Gerry Boyle to the Oireachtas Joint Committee on Climate Change and Energy Security Dáil Eireann
12 November 2008
Dear Mr. Chairman,
Thank you for the invitation to address your committee on developments in Irish agricultural practice and research of relevance to climate change.
As you are aware, climate change is identified as the most significant and threatening global environmental problem facing humanity today. Global consensus has recognised that significant cuts in global greenhouse gas emissions are needed over the next century in order to stabilise concentrations in the atmosphere at twice the pre-industrial level. The impacts of climate change on Ireland will be significant, but will be more damaging on many less developed countries less able to afford to take action or adapt.
As a first step towards tackling this threat, the United Nations Framework Convention on Climate Change (UNFCCC) required developed countries to put in place policies and measures with the objective of returning emissions of greenhouse gases to 1990 levels. In recognition of the need to take more substantial action, certain countries agreed legally binding targets in Kyoto in 1997, to reduce global emissions of six greenhouse gases by at least 5% below 1990 levels by 2012. The EU agreed to an 8% reduction by 2012 and as part of the EU target, Ireland has agreed to limit the growth in greenhouse gas emissions to 13% above 1990 levels by 2012. More recently, the 2007 Spring Council meeting of EU leaders agreed to a further reduction in GHG of 20% by 2020 compared to 1990, or 30% if a new global agreement is reached.
The main greenhouse gas in Ireland is carbon dioxide (CO2) mainly arising from the burning of fossil fuel in transport, heating and electricity generation. Irish emissions of other greenhouse gases, including methane (CH4) and nitrous oxide (N2O) are proportionately higher than most other developed countries (Figure 1). The goal of reducing emissions of methane and nitrous oxide presents a major challenge for the agriculture sector. However, meeting our Kyoto obligations and the commitments that will arise following Kyoto also presents opportunities, growing biomass crops as a source of energy is an example.
Agriculture accounted for 26.8% of total Irish greenhouse gas emissions in 2007 but this has been reducing over time from a figure of 35% of total emission in 1990. For example, agricultural emissions have decreased by 1.36m tonnes CO2 since 1990, or 6.8%. In an international context, Ireland’s profile of emissions is unusual in the developed world. New Zealand is the only developed country with a higher proportion of emissions from agriculture than Ireland, and the EU average is substantially below our level. This is due to the importance of agriculture in our economy.
Fig. 1: Emissions from agriculture in various countries worldwide. Source: UNFCC
Ireland is also unusual in the share of agricultural emissions coming from livestock. Over 50% of agricultural emissions is methane from enteric fermentation, and most of the remainder is nitrous oxide released from soils (Figure 2). This makes the problem of reducing our emissions more intractable, as we shall see later.
Fig. 2: Sources of agricultural emissions in Ireland. Source: EPA 2006
The 2007 provisional data represents a 3.8% reduction on 2006 for the agriculture sector (Figure 3). This is accounted for by a drop in cattle numbers of 3.1% (6.916m to 6.704m), a drop in sheep numbers of 7.6% (5.973m to 5.522m), and a drop in N fertilizer use of 4.1%.
Teagasc’s economic forecasting unit, FAPRI Ireland, regularly analyzes the effect of policy changes on agricultural incomes, outputs and inputs. As part of the process, forecasts are generated on key activity data used in emissions projections, and these are provided to the EPA to allow emissions projections to be developed. These data were last provided to the EPA in April 2008 and the resulting projections suggest that agricultural emissions will increase by 3% from 2006 to 2020. World markets including commodities, oil, and euro/dollar exchange rates have been very volatile this year. All of these affect our projections, and in a more recent analysis which included an updating of assumptions regarding the phasing out of milk quotas, the indications are that emissions by 2020 could be marginally lower than in 2005.
Challenges for reducing emissions
- Food security will require an increase in food production.
- Reducing emissions in Ireland by reducing food production will cause ‘leakage’ of emissions to whatever country increases production.
- Gaining credits for afforestation and biomass production for bioenergy is problematic.
- There are economic, social and moral implications of reducing the livestock herd.
- New technical solutions require a sustained research effort.
Progress to date
Significant progress has been made over the past number of years in reducing greenhouse emissions from agriculture. For example, improved nutrient management has led to a 35% reduction in nitrogen fertilizer use in the last 10 years, equivalent to a reduction of over 0.5m tonnes per annum of CO2 equivalent. We will continue to seek maximum efficiency of nutrient use in research and advisory programmes, ensuring that this trend continues. Also technological advances in dairy production has led to a drop of 12.4% in the amount of methane produced per kg of milk between 1990 and 2006 (Figure 4), thereby demonstrating the relationship between greater efficiency and reduced emissions. Efficient rearing of cattle leads to earlier slaughter and lower lifetime greenhouse gas emissions. Over the period since 1990, the age of slaughter of beef cattle has been significantly reduced. In 1990, 44% of male cattle were over 30 months of age at time of slaughter, this has now reduced to 15% in 2006 resulting in significant reductions in greenhouse gas emissions. Teagasc now has a significant research programme aimed at reducing greenhouse gas emissions from agriculture and assessing the opportunities for carbon sequestration that would help to minimize the impact of agriculture and land use on Ireland’s greenhouse gas emissions.
Methane is the main agricultural greenhouse gas produced in Ireland, mainly from enteric fermentation or digestion in the forestomach of ruminants such as cattle and sheep. It is a natural by-product of the digestion of feeds, particularly fibrous ones. Teagasc is looking at abatement strategies to reduce these emissions. These strategies include dietary modifications, additives or probiotics to reduce methane production, breed selection, increasing the length of the grazing season as grazed grass gives rise to less emissions than silage based diets, and improved pasture quality. The breeding of more efficient animals producing more product from a given amount of feed, and thus have less emissions per kg of milk or meat produced is very important. This requires a lot of basic science to understand the physiological and genetic factors controlling digestion and microbial processes, and emissions of methane from the rumen.
Nitrous oxide is produced from soils as part of the nitrogen cycle, and is a significant source of greenhouse gases. However, technology is being researched by Teagasc to minimize its release from soils. This research includes optimizing the application of organic and inorganic sources of fertilizer to further reduce nitrogen fertilizer usage and emissions. Other techniques being researched include the application of nitrification inhibitors and other fertilizer technologies, the more efficient use of clover as a nitrogen source, and reducing the load of nitrogen excreted onto pasture.
Other abatement strategies
Crops can be converted into a number of different energy carriers including transport fuels and electricity, they can also be combusted to generate heat and taken together can make a significant impact on mitigating the impact of greenhouse gas emissions (Table 1). Transport biofuels are currently being made from by-product materials (animal fat, recycled vegetable oil, whey) or using low-energy processes such as pure plant oil. First generation biofuel production in the country will mitigate approximately 87,000 tonnes CO2 eq from a new biodiesel plant will has become operational at New Ross. Further expansion of biofuel production is possible up to a maximum of perhaps 270,000 tonnes CO2 eq which would equate with our national 2% biofuel target. An ethanol-from-wheat plant now in planning will capture the fermentation CO2 for industrial use and will use biomass CHP for its energy needs. The fuels from these processes all achieve very high carbon abatement levels compared with their fossil equivalents, and they should be expanded to the maximum extent that our feedstock resources will allow. An ethanol plant would need a substantial amount of cereals, but this outlet will be needed to sustain and stabilise cereal production in a period when demand from animal enterprises is likely to decline. The development of one or two 1st generation ethanol plants would also pave the way for the 2nd generation, by establishing a logistics infrastructure, process expertise and markets for the produce.
Growing energy crops to meet the government co-firing target would mitigate approximately 830,000 tonnes of CO2 emissions if the target is to be supplied by energy crops exclusively. Energy crops, particularly willow, can also contribute to government heat targets (12% renewable heat by 2020). The GHG mitigation potential of using energy crops for heat depends on the acreage used for this purpose in addition to the types of fuels replaced but could amount to up to 1.7 MT CO2 eq. The anaerobic digestion of agricultural waste mixed with energy crops or other organic waste also has potential. However, obstacles include the high capital cost of the equipment together with the high cost of grid connection. Teagasc are currently working on aspects of this technology to assess it’s relevance for the future.
|Biofuels||270,000 t CO2|
|Electricity||830,000 t CO2|
|Heat||1,700,000 t CO2|
|C sequestration||50,000 t CO2|
|Total||2.85 MT CO2|
As you will appreciate, climate change is identified as the most significant and threatening global environmental problem facing humanity today. Global consensus has recognised that significant cuts in global greenhouse gas emissions are needed. Teagasc has an extensive research programme dealing with minimizing emissions from agriculture and developing innovative mitigation strategies and alternative land use options such as assessing the impacts of land use and land management change. We are also dealing with the policy issues and financial consequences of climate change and greenhouse gas mitigation. The goal of reducing emissions of methane and nitrous oxide presents a major challenge for the agricultural sector. However, meeting our Kyoto commitments also presents opportunities, growing biomass crops as a source of energy is an example. There is no doubt that research can play a significant role by developing innovative research based solutions, and application of these by the agricultural industry. Teagasc will continue to develop the most appropriate and cost effective solutions for dealing with this issue.