Carbon footprinting of New Zealand lamb from an exporting nation s perspective Stewart Ledgard 1 Mark Lieffering 1, Dan Coup 2 & Ben O Brien 3 1 AgResearch, New Zealand 2 Meat Industry Association NZ 3 Beef+Lamb NZ
Outline of talk 1. Drivers? 2. NZ sheep farm system 3. Methods 4. Results - sensitivity analyses - NZ and French case study systems - potential effects of mitigations
Drivers? International: Food-miles Carbon footprinting Supermarkets - Eco-labelling Becoming a supply requirement NZ is world s largest exporter of lamb (c. 40% of total)
Drivers? Within NZ: Emissions Trading Scheme - Carbon payment for tree planting - Carbon tax on fuel & electricity (c. 4-5%) - Animal CH 4 & N 2 O tax in 2013 or 2015
Features of NZ sheep farming simple farm systems (mixed sheep & beef) - average > 4000 sheep equivalents permanent perennial grass/clover pastures reliance on clover-n with little fertiliser-n all outdoors; no brought-in feed dual-purpose meat & wool sheep Seasonal production - spring lambing to match pasture growth pattern - opposite season to the Northern Hemisphere
Life cycle of lamb to the U.K. Fertilisers Lime Fuel Electricity Fuel Electricity Refrigerants Packaging Fuel Electricity Refrigerants Packaging Fuel Electricity Refrigerants Packaging Electricity Refrigerants Packaging Electricity Sheep & Beef farms (breeding & finishing) Meat processing plant Shipping (refrigerated container) Retail distribution Centre Supermarket Household Consumption Co-products: Wool Mutton Beef Packaging waste Co-products: Hides Wool Blood Offal Renderables Tallow Waste water Packaging waste Packaging waste Meat waste Meat waste Packaging waste Based on international standards (e.g. ISO 14040s norms; PAS 2050) Waste water
METHODS: data Farms: survey farm data (>460 farms over 7 farm classes) tier-2 method to estimate feed energy intake some NZ-specific E.F.s e.g. 20.9 g CH 4 /kg DM intake Meat processing plants: survey data from 11 plants (>40% all lambs) covered energy use, waste-water processing, refrigerants, consumables etc. Transport/retail/consumer/waste: mainly 2 o data modified for country-specific emissions
METHODS: co-products Farms: biological allocation between animal types on-farm economic allocation within sheep for meat and wool Meat processing plants: economic allocation between meat and co-products -skins, blood, renderables, tallow
RESULTS: Effects of method of allocation between meat and wool CO 2 N 2 O Methane
Lamb carbon footprint = 19 kg CO 2 -equiv./kg meat
Waste Water Cooking Fuel Electricity Other % 100 80 consumer Consume transport r Transport processor Processin g Retailing Waste Animal rumen methane 60 Far m farm Ocean Shipping Animal excreta N 2 O 40 Fuel & electricity Fertiliser & Lime 20 0 NZ domestic UK domestic
SENSITIVITY ANALYSES: meat processor Waste-water treatment: Changing from anaerobic processing to either aerobic processing or methane capture could reduce processing emissions by 22-38%, although this is only c. 1% of the total carbon footprint
SENSITIVITY ANALYSES: consumer Cooking method: roasting had 11% higher consumer/retail emissions than frying, or a 1% increase in total carbon footprint Inclusion of consumer travel gave an increase of up to 7% in the total carbon footprint (> all other transport stages combined) Williams et al. 2008
Case study of NZ and French sheep farm systems 20 160 days housing + cereal crop + concentrates 15 kg CO 2 - equiv./ kg live-weight sold 10 Drought year 90 days housing + concentrates CO 2 fuel + electricity N 2 O+CO 2 fertiliser N 2 O grazing excreta N 2 O manure 5 Methane 0 2004/05 2008/09 Pasture Housed+crop New Zealand France 22% allocation to wool 0.3% allocation to wool Lorinque, Ledgard, Gac, Boyes & Le Gall, unpubl.
How can we reduce emissions? i. increase animal production efficiency Methane (kg CH 4 /kg carcass wt) 1.1 1.0 0.9 0.8 0.7 0.6 Compared to 1990, NZ sheep farms in 2009 produced slightly more lamb meat, but from a 43% smaller flock 1990 1992 1994 1996 1998 2000 2002 2004 2006 Year
Hypothetical mitigation scenarios on case study farms % reduction in farm Effect on GHG emissions/kg lamb profit lamb growth : finish 1 month earlier 4-12 ++ replacement rate: ewes last 1 yr longer 5-7 + lambing% : by ~ 20% 3-5 ++ ewe hogget lambing : 80% 2-5 + no N fertiliser use on pasture 1-3 - nitrification inhibitor use (DCD) ~ 9 - -
Summary: Carbon footprint of NZ lamb of 19 kg CO 2 -equiv./kg meat: covers whole life cycle, but dominated by farm stage depends on methodology choices lower from low-input grazing systems decreased over time with increased feed conversion efficiency potential reduction with some mitigations