Life cycle analysis of bread production a comparison of eight different options G.A. Reinhardt, J. Braschkat, A. Patyk & M. Quirin ifeu Institute for Energy and Environmental Research Heidelberg 4 th International Conference: Life Cycle Assessment in the Agri-food sector Horsens (DK) from 6. 8. October 2003
Questions How to produce bread being most environmentally friendly? Which of the process steps, including transports, do account for the highest or lowest environmental effects? At which processes is it feasible to introduce ecological optimisations or to reduce environmental implications, and what are the corresponding recommendations?
Goal definition Functional unit: 1 kg bread ready for consumption at home. System boundaries: Production in Germany. Pre-chains: split worldwide. Others: Basic data, assumptions, allocation issues et cetera: see paper.
Impact Assessment Environmental impact Indicator Parameter Resource depletion cumulated Crude oil, natural gas, non-renewable mineral coal, lignite, primary energy uranium ore Greenhouse effect CO 2 -equivalents CO 2, N 2 O, CH 4 Ozone depletion N 2 O N 2 O Acidification SO 2 -equivalents SO 2, NO x, NH 3, HCl Eutrophication PO 4 -equivalents NO x, NH 3 Photo smog Ethene-equivalents CH 4, NMHC Land use ha ha
Life Cycle of the bread production seed pesticide fertiliser fuel cultivation electricity electricity grain fuel oil transport natural gas fuel oil drying grain T flourproduction flour T baking process home T retailer T bread
Energy demand 5.0 4.5 bread transport MJ/kg bread 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 baking: factory process heat gas boiler process heat oil-boiler electricity supply flour transport industrial mill Electricity supply grain transport drying, stocking pesticide nitrogen transport to the farm harvest potassium phosphorus seed pesticide application fertilizer application seed application plowing harrowing baking process: = factory flour production: = industrial mill crop production: = conventional
Differentiation of important processes Crop production: conventional organic Flour production: industrial mill domestic mill Baking technologies: large bread factory bakery domestic bread maker
8 scenarios to produce bread conventional organic industrial mill domestic mill industrial mill factory bakery home home home home bakery factory 1 2 3 4 5 6 7 8
Energy demand 10.0 10,0 farming milling baking transport 8,0 8.0 MJ/kg bread 6,0 6.0 4,0 4.0 2,0 2.0 0,0 0.0 industrial mill factory bakery home domestic mill
Energy demand 10.0 10,0 farming milling baking transport conventional farming organic farming 8.0 8,0 MJ/kg bread 6.0 6,0 4.0 4,0 2.0 2,0 0.0 0,0 industrial mill dom. mill industrial mill dom. mill factory bakery home factory bakery home
Greenhouse effect 800 farming milling baking transport conventional farming organic farming g CO2-eqiv./kg bread 600 400 200 0 industrial mill dom. mill industrial mill dom. mill factory bakery home factory bakery home
Ozone depletion 0.60 0.50 farming milling baking transport conventional farming organic farming g N2O/kg bread 0.40 0.30 0.20 0.10 0.00 industrial mill dom. mill industrial mill dom. mill factory bakery home factory bakery home
Acidification g SO2-equiv./kg bread 3.00 2.50 2.00 1.50 1.00 0.50 farming milling baking transport conventional farming organic farming 0.00 industrial mill dom. mill industrial mill dom. mill factory bakery home factory bakery home
Land use 2,0 2.0 conventional farming organic farming 1,5 1.5 m 2 /kg bread 1,0 1.0 0,5 0.5 0,0 0.0
LCIA results crop production milling baking transport 10.0 Energy demand 800 Greenhouse effect MJ/kg bread 8.0 6.0 4.0 2.0 g CO2-eqiv./kg bread 600 400 200 0.0 0.60 Ozone depletion 0 3.00 Acidification g N2O/kg bread 0.50 0.40 0.30 0.20 g SO2-equiv./kg bread 2.50 2.00 1.50 1.00 0.10 0.50 0.00 0.00 0.40 Eutrophication 2.00 Land use g PO4-equiv./kg bread 0.30 0.20 0.10 m 2 /kg bread 1.50 1.00 0.50 0.00 0.00 con org
Results Organically produced grain has to be preferred to grain that was produced conventionally regarding all impact categories except land use. Flour may be produced preferably in an industrial mill rather than in a domestic mill. Ranking the bread baking process from the most to least advantageous option results in the order: factory, local bakery and domestic bread maker. Sensitivity analysis for transportation
Transport by the consumer conventional crop production organic crop production retailer retailer industrial mill domestic mill industrial mill domestic mill retailer retailer factory bakery home home factory bakery home home retailer retailer home home home home
Assumptions Basic scenario Transport of bread from the bakery: by bicycle. Transport of grain, flour or bread from the supermarket: by car without driving detours (on the way from / to work etc.). Extreme scenario Transport of 1 kg of bread, flour or grain by car (4 km round trip).
Sensitivity analysis: transport farming milling baking transport 30.0 25.0 extreme scenario MJ/kg bread 20.0 15.0 10.0 5.0 bandwidth basic scenario 0.0 industrial mill factory bakery home domestic mill
MJ/kg bread 30.0 25.0 20.0 15.0 10.0 5.0 0.0 Sensitivity analysis: transport farming milling baking transport transport home Energy demand Greenhouse effect g CO2-eqiv./kg bread 1600 1400 1200 1000 800 600 400 200 0 extreme scenario bandwidth basic scenario g N2O/kg bread 0.80 0.70 0.60 0.50 0.40 0.30 0.20 0.10 Ozone depletion g SO2-equiv./kg bread 6.00 5.00 4.00 3.00 2.00 1.00 Acidification 0.00 0.00 0.80 0.70 Eutrophication g PO4-equiv./kg bread 0.60 0.50 0.40 0.30 0.20 0.10 0.00
Transportation: Break even points 25 20 Energy demand farming milling baking transport transport home extreme scenario MJ/kg bread 15 10 5 0 0.5 km 0.9 km home bakery factory 4 km factory bandwidth basic scenario
Transportation: Break even points Energy demand farming milling baking transport transport home 25 extreme scenario 20 MJ/kg bread 15 10 0,2 km 4 km bandwidth 5 0 basic scenario conv. farming organic farming
Transportation: Break even points Energy demand Acidification farming milling baking transport transport home 25 4 MJ/kg bread 20 15 10 5 0,2 km 4 km g SO2-equiv./kg bred 3 2 1 3 km 4 km 0 conv. farming organic farming conv. farming organic farming 0
Results Advantages and Disadvantages of each processing step: Farming: Milling: Baking: Organic Industrial mill Bread factory bakery Conventional Domestic mill Domest. bread maker For the ultimate appraisal the transport of grains, flour or bread respectively, by the consumer is of evident importance.
Recommendations If land use is more important than all the other environmental impact categories: grain from conventional farming has to be preferred to grain that was produced organically If land use is of minor relevance compared to saving of resources, greenhouse effect, ozone depletion, acidification and eutrophication: grain from organic farming has to be preferred to grain that was produced conventionally
Recommendations Bread factories / Supermarkets Use cereals from organic production. Mount campaigns, that customers buy as much as possible at once and if possible without driving detours (buy on the way from / to work etc.). Bakeries Use cereals from organic production. Optimise the energy demand. Mount campaigns, that customers don`t use the car to buy bread.
Recommendations Consumer Buy bread from organically grown cereals in a supermarket. - If bread from organic grain is not available in the supermarket, customers have to ask for it to increase the demand and... -... buy it in a bakery. If baking at home, cereals from organic production and flour from industrial mills have least environmental implications. - Use a domestic bread maker instead of an oven. - If an oven is used, increase the degree of utilisation. Don t use a car to transport bakery products. If a car is used, buy also other groceries and without driving detours (on the way from/to work etc.).
Thank you mange tak! Dr. Jörg Braschkat Dr. Andreas Patyk Dr. Markus Quirin