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LCA GHG methodologies for bioenergy, EEA, Copenhagen, 10/06/2008 1 Robert Edwards European Commission Joint.

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Presentation on theme: "LCA GHG methodologies for bioenergy, EEA, Copenhagen, 10/06/2008 1 Robert Edwards European Commission Joint."— Presentation transcript:

1 LCA GHG methodologies for bioenergy, EEA, Copenhagen, 10/06/2008 1 Robert Edwards robert.edwards@jrc.it robert.edwards@jrc.it European Commission Joint Research Centre Institute for Energy Renewable Energies Unit Ispra, Italy Joint Research Centre (JRC) The European Commission’s Research-Based Policy Support Organisation “Robust science for policy making” LCA METHODOLOGY

2 Accounting for by-products – purpose of LCA determines method Indirect (displacement) emissions N 2 O emissions from soils LCA METHODOLOGY  Renewable Energies LCA GHG methodologies for bioenergy, EEA, Copenhagen, 10/06/2008

3 Accounting for by-products: Substitution Substitution (=system expansion) models reality. It tells you how much GHG you save in the whole economy caused by a particular pathway to making biofuel Most biofuels pathways save GHG in more than one sector: transport, heat, electricity, animal feed. Substitution does not say in which sector the GHG is saved “GEARING” PROBLEM …is caused by attributing savings in all sectors only to the biofuel production…....

4 Substitution models reality: (extra biofuels scenario) – (reference scenario) Biofuel crop on a field processing refinery crude oil emissions from what the by-product substitutes e.g. soy-meal cake distribution by-product e.g. rapeseed cake car distribution Car + alternative use of the field ACCOUNTING FOR BY-PRODUCTS: Credit for the emissions saved by not making what the by-product substitutes GHG saved depends on the use of the byproducts Gives the effect of biofuels on total GHG emissions But it does not tell us how much GHG is saved in the transport fuel sector …because by-products are used in other sectors, e.g. heating, animal feed...

5 “GEARING” PROBLEM IN SUBSTITUTION %GHG saved = GHG saving in all sectors unit of biofuel product the more GHG you can save in all sectors, and the less biofuel you make, the better the result. e.g. BtL plants with the best greenhouse gas balance are the ones with the smallest production of biofuel and the largest export of bioelectricity

6 “GEARING” PROBLEM IN SUBSTITUTION DISAPPEARS WHEN COMPARING BIOMASS USES %GHG saved = GHG saving in all sectors unit of biofuel product tonne of biomass used or hectare of average EU cereal land Therefore substitution seems the best methodology for comparing different biomass uses.

7 Accounting for by-products – purpose of LCA determines method Indirect (displacement) emissions - “arrived in 2007”; the science isn’t ready yet N 2 O emissions from soils LCA METHODOLOGY  Renewable Energies LCA GHG methodologies for bioenergy, EEA, Copenhagen, 10/06/2008

8 Using crops for biofuels (except on set-aside land) will displace food production outside EU: where? what are the farming emissions? what is the change in land use? (extra biofuels scenario) – (reference scenario) DISPLACEMENT OF FOOD PRODUCTION: EMISSIONS EFFECTS EU field growing crop for biofuels EU field growing crop for food growing extra food outside EU these two roughly cancel out

9 THERE ARE 2 TYPES OF INDIRECT EMISSIONS! Indirect ANNUAL emissions, from fertilizer, tractor etc. –could be higher or lower than EU farming emissions –never evaluated! Indirect Land Use Change emissions –could be enormous - hot debate!

10 ESTIMATING indirect land use change emissions for feedstock production by individual batch: –try to follow causation as far as possible, then add a uniform “adder” for all the rest by feedstock type: –using agro-economic models + ecological zones or soil C –not much difference between e.g. different cereals –big difference between vegetable oils, cereals and sugar. one value for all crops? –simple historical arable land expansion allocated between demand drivers to find average value per tonne.

11 INDIRECT EMISSIONS Feedstock from: Direct emissions Indirect emissions Diverted food = buying from commodity market NOYES Change in crop e.g. wheat to rapeseed fodder to wheat cereals to energy crops changeYES New arable landYES (also from land use change) NO

12 Accounting for by-products Indirect (displacement) emissions –Science isn’t ready N 2 O emissions from soils LCA METHODOLOGY  Renewable Energies LCA GHG methodologies for bioenergy, EEA, Copenhagen, 10/06/2008

13 N 2 O Emissions IPCC gives recommendations for estimating N 2 O emissions for Kyoto, but with huge error range Top-down estimates (Cruzten) even more rough

14 N 2 O from wheat fields in EU (JRC calculations) kg/ha/y depends on: 1. SOIL 2. Climate 3. Which reference crop? 4. Yield 5. N fertilizer input } geographic crop distribution N 2 O g/GJ (Average for EU15) JRC estimated EU-average N 2 O emissions per crop …but it varies by 1000x between fields! reference

15 N2O emissions in JEC-WTW sophisticated estimate of EU-average N 2 O per crop with ~30% error range still the biggest source of uncertainty account for ~15-60% of net GHG emissions for 1 st generation biofuels (not including indirect effects)

16 Localizing N 2 O emissions? N2O depends firstly on soil + climate possible but complex to estimate local N 2 O emissions in EU (and then, with ~50% range of error) but if the feedstock is otherwise used for food it’s irrelevant Outside EU, generally too little data for anything better than IPCC: more than factor 9 uncertainty.

17 Accounting for by-products –substitution for policy studies, –allocation for legislation Indirect (displacement) emissions –annual: never evaluated –land use change: science isn’t ready N 2 O emissions from soils – large uncertainties LCA METHODOLOGY SUMMARY  Renewable Energies LCA GHG methodologies for bioenergy, EEA, Copenhagen, 10/06/2008

18 Brussels 28/05/2008 Hart Conference: Low C fuels Implemention 18 Robert Edwards robert.edwards@jrc.it robert.edwards@jrc.it European Commission Joint Research Centre Institute for Energy Renewable Energies Unit Ispra, Italy Joint Research Centre (JRC) The European Commission’s Research-Based Policy Support Organisation “Robust science for policy making” THE END

19 SPARE SLIDES

20 FOSSIL ENERGY BALANCE Per 1 MJ ethanol: Input:Fossil input: 2.5 MJ wheat 0.5 MJ 100 MJ straw 2 MJ - 1 MJ petrol -1.1 MJ - 30 MJ fossil elect. - 80 MJ Fossil fuel (saved) - 78.6 MJ per MJ ethanol” Here, all the fossil energy savings from (bioelectricity + biofuel) production are attributed only to the biofuel… …but most of it was saved in the electricity sector! = total fossil fuel saved by (bioelectricity + bioethanol) ethanol produced extreme example: BIO-ELECTRICITY + ETHANOL PROCESS - “biofuel” scenario reference scenario 2.5 MW wheat 30 MW electricity 1MW ethanol Wheat-Ethanol plant heat Electricity plant 100 MW Straw1.1 MW crude oil 1MW petrol 30 MW electricity 80 MW fossil fuel Straight substitution for bioelectricity by-product:

21 1.1 MW crude oil 1MW petrol 30 MW bioelectricity 100 MW straw - reference scenario = fossil fuel saved by ethanol production ethanol produced Using a credit for electricity from the same fuel, we balance out the fossil fuel saving in the electricity sector, and find the savings in the transport fuel sector You find fossil fuel saved in transport fuel sector by balancing the bioelectricity production… “biofuel” scenario 2.5 MW wheat 30 MW bioelectricity 1MW ethanol Wheat-Ethanol plant heat Electricity plant 100 MW Straw FOSSIL ENERGY BALANCE Per 1 MJ ethanol: Input:Fossil input: 2.5 MJ wheat 0.5 MJ 100 MJ straw 2 MJ - 1 MJ petrol -1.1 MJ - 30 MJ bioelectricity - 2 MJ Fossil fuel (saved) - 0.6 MJ per MJ ethanol

22 1.1 MW crude oil 1MW petrol 30 MW bioelectricity 100 MW straw - reference scenario = fossil fuel saved by ethanol production ethanol produced Using a credit for electricity from the same fuel, we balance out the fossil fuel saving in the electricity sector, and find the savings in the transport fuel sector You find fossil fuel saved in transport fuel sector by balancing the bioelectricity production… “biofuel” scenario 2.5 MW wheat 30 MW bioelectricity 1MW ethanol Wheat-Ethanol plant heat Electricity plant 100 MW Straw FOSSIL ENERGY BALANCE Per 1 MJ ethanol: Input:Fossil input: 2.5 MJ wheat 0.5 MJ 100 MJ straw 2 MJ - 1 MJ petrol -1.1 MJ - 30 MJ bioelectricity - 2 MJ Fossil fuel (saved) - 0.6 MJ per MJ ethanol another way of looking at it is that we have subtracted bioelectricity from the mixed process

23 “GEARING” PROBLEM: simple illustration A processor makes biodiesel from oilseed. He calculates that he saves “G” tonnes CO2 per tonne biodiesel. -Now, suppose he decides to export half his vegetable oil to make detergent. -Assume that 1tonne vegetable oil used for detergent saves the same GHG as making it into biodiesel. -He gets 1/2G credit for his detergent export, so he is still saving G tonnes of GHG from the same quantity of oilseeds. -But his only making half as much biodiesel, so now per GJ biodiesel, he is saving “2G” tonnes of GHG -(and he is also saving 2G tonnes GHG per GJ detergent!) GEARING ONLY HAPPENS WHEN WE QUOTE GHG SAVINGS / UNIT OF PRODUCT no problem for savings/€ or savings/ha

24 Substitution does not say how much GHG is saved in the transport sector. Instead it calculates the total GHG saved in all sectors and attributes this just to the biofuel. For certification of biofuels, we need to know how much GHG they save in the transport sector. By-products are exported out of the transport fuel sector before they are used. The calculation for the GHG saved in the transport fuel sector should be simpler because it should not depend on the use of the by-products estimating emissions in the transport sector

25 What if we export rapeseed cake? By the same rigorous (“bioelectricity”) logic, to work out the emissions effect in the transport fuel sector we need to make a credit based on “rapeseed cake farming”. Because there is no “rapeseed cake tree”, we cannot solve this problem rigorously We need to make an assumption…. estimating emissions in the transport sector (cont…)

26 We can allocate a PROPORTION of the total process emissions to byproducts, according to a rule : e.g. “The upstream emissions for making by-products are proportional to: 1. …their dry mass” 2....their energy content” 3....their price” … etc. All are wrong in principle, but this is the only way to estimate GHG savings in the transport sector - simpler than substitution: -- don’t have to guess what a by-product substitutes Chosen for RE directive proposal - doesn’t change with time like price - but needs adjustments for quality: electricity, straw… Electricity export uses JEC-WTW methodology, as explained

27 How much arable land expansion? …the AREA vs. YIELD DEBATE The historical fallacy: “ most of the increase in demand has historically been met by yield increases; little by increased area” …that reasoning attributes all technical progress to an increase in demand historically real prices fell as yields rose : does that mean higher prices mean lower yields?

28 Misunderstandings about indirect effects “ deforestation in Indonesia is caused by logging” - only the deforested area actually planted with oil palms is considered. “Sugar cane is far from the rainforest” Most deforestation happens anyway, but studies indicate soybeans are also a driver We know that little palm oil goes into biofuels: that’s why it’s called an indirect effect ….of taking 19% of the world’s vegetable oils (10% EU biodiesel 2020) nobody says all the extra demand will come from area increase: there will be some yield increase too

29 2. EMISSIONS FROM GASOLINE AND DIESEL: refinery Introducing an alternative fuel means a reduction in either diesel or gasoline output One can model the reduction in refinery emissions. -

30 results from JEC-WTW study http://ies.jrc.cec.eu.int/WTWhttp://ies.jrc.cec.eu.int/WTW Well-to-Tank emissions from fossil fuels 2013 % of product energy used gCO 2 eq/MJ product GasolineDieselGasolineDiesel Crude extraction and conditioning* 3%3.63.7 Crude transport1%0.9 Refining in EU8%10%7.08.6 Distribution and dispensing 2%1.0 TOTAL14±2 %16±2 %12.5 ±214.2 ±2 *without flaring

31 DG-AGRI oilseeds projection consumption as food EU production imports consumption for biodiesel (5.75% target) Extra demand for oilseeds is met mostly by imports


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