Minimising Nitrous Oxide Intensities of Arable Crop Products

Transcription

1 Minimising Nitrous Oxide Intensities of Arable Crop Products GHG Emissions in Renewable Feedstock Production Accounting and Mitigation, 23 rd May 2017, Brussels Prof. Roger Sylvester-Bradley Head of Crop Performance, ADAS Dr Harley Stoddart Policy Manager, AHDB Dr. Steven Anthony Head of Environment Modelling, ADAS

2 Minimising Nitrous Oxide Intensities of Arable Crop Products 2009 to Life Cycle Assessment - Feedstock - Products 2. Field Experiment - Fertiliser Rate - Crop Residue Objective: Better GHG Accounting of Arable Feedstocks for Products Project sponsored by Defra & Scottish Government through the UK Sustainable Arable LINK programme 3. Modelling - Statistical Synthesis - Upscaling 4. Integration - Mitigation Scoping Bioethanol from Feed Wheat Biodiesel from Oilseed Rape Bioethanol from Sugar Beet

3 Renewable Energy Directive (2009) Promotion of the use of energy from renewable resources Target at least 10% of Transport Energy Consumption from Renewable Sources Biofuels must achieve sustainability criteria to receive government support and count towards renewable energy targets; Sustainability Criteria Greenhouse gas savings in comparison to fossil fuels % Saving 2017 Existing Production Plant 50% Post 2017 New Production Plants 60% 30% of renewable liquid transport fuel used in the UK is sourced from UK feedstocks.

4 UK Agricultural GHG Research Platform 2011 to 2017 Nitrous oxide Synthesis Emissions Modelling (Ammonia) Mitigation Meta-Analysis Farm Practices Survey Methane New Inventory Model Regional Sensitivity Performance Monitoring Prof. David Chadwick Dr Steven Anthony Dr. John Moorby & InveN2Ory 2 ResearCH 4 Synthesis

5 UK Platform Family of Field Experiments Joint Experiment Protocols, Laboratory Ring Tests and Technical Training IPCC Compliant Monitoring (12 Months) Experiment Crop Site years AC0101 Winter Wheat 4 AC0101 Grass 2 NT2605 Winter Wheat 2 NT2605 Grass 3 NI Grass 1 NI Winter Wheat 1 NI Winter Barley 1 AC0116 Winter Wheat 2 AC0116 Winter Barley 1 AC0116 Grass 5 MIN-NO Winter Wheat 9 MIN-NO Spring Barley 4 MIN-NO Sugar Beet 3 MIN-NO OSR 5 MIN-NO Winter Barley 3 MIN-NO Sites Edinburgh Gleadthorpe Terrington Boxworth GHG Platform Sites

6 Task 1. Life Cycle Assessment Farm and Field Records Sourced by Industry Partners Feed Wheat Bioethanol (n 592) Oilseed Rape Biodiesel (n 353) Feedstock Footprint Product Footprint Publicly Available Specification 2050 (PAS2050; British Standards Institute, 2011) IPCC (2006) Default Emission Factors Renewable Energy Directive Approach (RED; European Commission, 2009) 60 to 75% of default footprints are N and N 2 O related

7 Task 1. Life Cycle Assessment Feed Wheat Bioethanol (n 592) Oilseed Rape Biodiesel (n 353) RED 35% Non Crop Other Crop Non Crop Other Crop RED 50% *RED 60% Soil N 2 O Soil N 2 O * 47% Exclusion * 88% Exclusion Sensitivity Analysis: Crop Yield > Fertiliser Nitrogen > Residue Management > Fertiliser Type)

8 Task 2. Field Experimentation 24 Fertiliser Experiments Wheat, W&S Barley, OSR, Sugar Beet Large Rainfall Range (500 to 1700 mm) 5 N Rates (0, 40, 80, 120, 160% Rec. Rate) Commercial Timing of N Splits 3 Crop Residue Experiments Cereals, OSR, Sugar Beet & Pulses Direct Emission Factor 21 out of 24 results <1% Site average of 0.68% N-supply-related emissions, ha -1 N-balance-related emissions, ha -1 crop production, t ha economic 0 optimum N Supply, kg ha -1 Fertiliser N Responses 10 Linear 11 Curves 3 - Other Artefact of Rainfall & N Timing Crop Residue Emission Factor Zero for brown litter

9 Task 3. Statistical Modelling Direct Soil N 2 O Emissions Restricted Maximum Likelihood (REML) Regression Model Statistical modelling Related N 2 O to the fertiliser N applied, annual rainfall and soil clay content Crop type or soil organic matter did not have significant effects The final MIN-NO Model N 2 O-N emitted (g/ha/year) = [Transformed as: log(710 + N 2 O-N emitted)] 24 EXP (n 316) * N applied (kg/ha) * Annual Rain (mm) * Clay% * Rain*Clay%/100 Background f ( Rainfall, Nitrogen, Clay, Rainfall Clay)

10 Task 3. Upscaling Accounting for Location and Annual Rainfall Variability Reference UK emission estimates (IPCC 2006) Total Agricultural Direct from fertiliser N Direct from arable fertiliser N 40.1 kt N2O-N 11.2 kt N2O-N 6.9 kt N2O-N Annual Rainfall (mm) Wheat & Oilseed Rape MIN-NO Model extrapolation of EF1 Based on 5 km grid activity data x 30 years weather data Crop Specific Distribution of Fertiliser Rates (BSFP) For all major arable crops New EF1 applied to arable land reduces UK N2O-N emission by 3.7 kt yr-1 UK Arable EF1 0.46% ( 0.07%)

11 UK Agricultural GHG Platform Synthesis Arable and Grassland Integrated in a Single Model 38 EXP (n 662) Site Average Direct Emission Factor of 0.79% (Arable and Grass) Field Nitrogen Rate for Wheat and Oilseed of 200 kg ha -1 N (BSFP, 2015) ~ 0.56% f ( Rainfall, Nitrogen, Rainfall Nitrogen)

12 Task 4. Integration (Part) Proposals for Revised EF Comparison with Standard Emission Factors Reduction in Biofuel GHG Intensity 1. Revised EF1 for Direct Fertiliser N2O (0.46 vs 1%; Project MIN-NO): * 2. Abated Fertiliser Manufacture (3.52 vs 6.3 kg CO2e kg-1 N; Fertilizers Europe, 2014): 3. Revised FRACGAS for NH3 (3 vs 10%; Project NT26): 12% 14% 2% Revised Average Intensity at / below RED 60% Target * 3.4 kg CO2e kg-1 N GrowHow UK Fertiliser Manufacturer Fuel baseline standard set at 88.3 g CO2e/MJ. Biodiesel Energy Density 33 MJ/l Bioethanol Energy Density 21 MJ/l

13 Task 5. Mitigation Reducing Fertiliser Use Using Revised Emission Factors Yield GHG Intensity GHG Intensity (ILUC) Excluding Indirect Land Use Change (ILUC): NOPT: 305 kg CO2e t-1 GHGMIN: 269 kg CO2e t-1

14 Task 5. Mitigation Chemical Additives Dicyandiamide (DCD) Nitrification Inhibitors and Ammonium Nitrate Fertiliser * 1. Project AC0116: 9 Laboratory and Field Experiments 4 Arable Sites Average Reduction : 68% Arable 25% Grass Emission Reduction by Site / Soil ** 2. Project AC0213: 14 Field Experiments 3 Arable Sites Average Reduction : 34% Arable 47% Grass * McGeough et al. (2016) Soil Biology and Chemistry ** Misselbrook et al. (2014) Environment Research Letters Effect Limited by Clay and Organic Matter Content

15 Task 5. Mitigation Nitrogen Use Efficiency Soil Nitrogen Efficiency Fertiliser Nitrogen Efficiency Plant Breeding Plant Breeding / Fertiliser Technologies NOPT GHGMIN 40% Reduction in NOPT 20% Reduction in Emission & Intensity

16 Limits to Mitigation Reduced Contribution of Fertiliser Related Direct N2O to GHG Footprint But consider also substitutes (Triticale); soil compaction; manure management; crop rotation; etc.

17 Concluding Main MIN-NO Outcomes Regionalisation of EF1 Reduction in UK N2O Emission Reduced Footprint for Arable Products Improved Viability of Biofuels especially biodiesel * Foundation for a 2nd Revision of NUTS2 Submission to Dft and EC (May 2016) Foundation for Further Research * Regional Emissions from Biofuels Cultivation

18 Thank You MIN-NO Contacts: Government: Industry: Farming: Biofuels: Research: Project sponsored by Defra & Scottish Government through the UK Sustainable Arable LINK programme