The beginnings of a Biochar Integrated Assessment Model : Looking into Biochar from a system perspective

Transcription

1 The beginnings of a Integrated Assessment Model : Looking into from a system perspective UK Conference 011 Edinburgh, May 11, 011 Sohel Ahmed, Rodrigo Ibarrola, Jim Hammond, Simon Shackley. Integrated Assessment Model (BIAM) Purpose: To assess the viability and likely social, economic and environmental impacts, of widespread biochar production, use and deployment at different scales; Objective: to explore the practical issues which will arise during the design and deployment of biochar systems. How? System approach encompassing different aspects (carbon balance, energy balance, economic feasibility Where? UK initial scope, but flexible enough to be applied anywhere in the world PBS BIAM Multi- feedstock

2 Pyrolysis System (PBS): sources to sinks PBS: A combination of a specified pyrolysis technology, transport, distribution and storage infrastructure and application of biochar (Shackley, et. al, 010). This is very much dependent on scale and sources of biomass!!. 1. Multi- feedstock transport Multiple biomass sources transport storage PBS unit Production, and technology engineering projects (external data) Storage.Life-cycle.techno-economic PBS BIAM UKBRC soil tool kit &Field trials (external data) Multi- feedstock transport Sinks (application of biochar to soils) PBS main focus components Feedstocks (virgin& non-virgin) Properties (chemical compunds, heating values, carbon content, moisture content, etc Availability (by GOR) Pyrolysis process Preparation & handling Captial cost Operation & maintenance Labour cost & fuel cost Output: Costs, Scale organic farming systems focus Transport network & cost Potential Sites travel cost (scale dependent on the plant) Scale Travel speed Time Frequency Impasses Soil inputs Energy ratio LandLand-use Yield inputs balance Land-use/land-cover change Costs implications Nutrient balance Additional feedstock parameters: AD and then digestate, wood ash, compost, sewage sludge Raster data for most virgin sources and point data on many non-virgin sources Storage Suitability mapping Scale and time Output Output costs & additional indicators from LCA Eutrophication potential, other costs acidification potential, land-use/land cover change maps (changes in sources and sinks) eco-system services (e.g. NO), water demand etc. PBS BIAM Multi- feedstock

3 Analysis performed so far What sources of biomass feedstocks can be used? Virgin: Straw Forestry residues Energy crops Arboricultural arisings Sawmill residues Non virgin: Sewage sludge Paper sludge Draff (remains from whisky production) Wood waste PBS BIAM Multi- feedstock What sources of biomass feedstocks can be used?-qualitative multi- Six aspects considered for the : Availability: How much is generated (~millions of tonnes), where are the sources (dispersed through different regions, localised etc.); Competition: other activities that need the supply (e.g. wood waste for recycling, straw for energy generation, sludge for land spreading, etc.) Suitability for PBS: potential contaminants (heavy metals, PAHs), pelletization needed, moisture contents, energy densities; Quality of biochar: levels of ash (P, K etc.), porosity, carbon content; Constraints: geographical, costs, farmer and public perceptions, feedstock consistency, regulations; Logistics/locations: onsite demand of bioenergy, existence of distribution networks, separation processes. PBS BIAM Multi- feedstock

4 What sources of biomass feedstocks can be used?-qualitative multi- Criteria Straw (wheat, barley and OSR) waste wood Forestry residues energy crops paper sludge Sewage sludge AA saw mill draff clean treated now future now future scor e availability Competition (within feedstock) suitability for PBS S: and L: 1 - -* -* quality of biochar * - -? constraints * 1 -* - - logistics/locations Total out of now - future PBS BIAM Multi- feedstock What is the potential carbon that can be achieved? From virgin feedstocks: Source: Hammond J, Shackley S, Sohi S P and Brownsort P 011 Prospective life cycle carbon for pyrolysis biochar systems in the UK. Energy Policy 9, 66-6 PBS BIAM Multi- feedstock

5 What is the potential carbon that can be achieved? From non virgin feedstocks:!!"!!" """ Source: Ibarrola R, Shackley S, Hammond J: Pyrolysis biochar systems for recovering biodegradable waste: A life cycle carbon Waste Management (011 (submitted)). PBS BIAM Multi- feedstock What are the estimated costs associated to PBS? Multiple biomass sources Pyrolysis unit Storage 7-1 Virgin feed: -7 Non-virgin feed: 0 Avoided gate-fees (wastes): 89-1 Transport -8 to Capital : -101 Operation (gas, labour & maintenance): Electricity: sales: 7 and subsidy: 7 Sinks Transport 0-19 (application of biochar to soils) Pyrolysis-biochar system (PBS): from sources to sink Numbers indicate cost ranges (in t -1 biochar) per process stage PBS BIAM Multi- feedstock

6 What are the estimated costs associated to large scale PBS? Green waste & Sewage sludge C&I veg and animal waste Straw SRC+FRs Miscanth us Sawmill Residues SRF Canadian FRs Waste Wood sales of electricity ROCs avoided gate fee capital cost feedstock transport storage natural gas labour plant costs application to field Net cost Source: Shackley S, Hammond J, Gaunt J, Ibarrola R, 011 Feasibility and costs of biochar deployment in the UK. Abatement (accepted). PBS BIAM Multi- feedstock part

7 PBS process: sources to sinks. transport transport Multiple biomass sources storage PBS unit Storage transport Sinks (application of biochar to soils) Simply putsources transport PBS BIAM Multi- feedstock sinks Sources of feedstocks F Sources 0 17 Kilometers Sinks What is?

8 Wood-based mills Distilleries and settlements??

9 Sinks Suitability mapping and to explore sinks Factors to consider: Soil characteristics (SOC, texture, ph, NVZ) Designated protection areas Transport cost from Source, PBS sites Distance from water bodies Customize suitable surface of sinks Different variables can be added together (equally weighted/ differentially weighted) based on our judgement on agronomic value to be added and/ carbon sequestration potential? Organic carbon Soil texture structure Soil Sites of Specific Scientific Interest Ramsar National Nature Reserves Environment?

10 What is multi- Decision ()? Systematic way to select the best available alternatives based on different opinions and conflicting priorities and values. No straight rules to combine different too complex information to be overviewed at once Large number of decision alternatives no optimal solution -- conflicting priorities and values and -- problems and /decisions are often surrounded by uncertainty provides appropriate platform to reflect/consider all these.? variables included Problem to solve (objective): to explore locations for PBS in Scotland Economic variables Environmental variables Soil variables (work ( in progress) arable lands woodlands major roads Environmentally sensitive sites or sites Sites with landscape and / biodiversity values (e.g. Sites of Special Scientific Interests (SSSIs) Soil characteristics that biochar can potentially improve (e.g. Soil Organic, ph, Structure, Nitrate Vulnerable Zones etc.)?

11 Overview on assumptions for multi- Decision Analysis () Economic: Sources of woody resources are considered more important than other variables. Environment: We cant deploy biochar in urban areas, environmentally sensitive areas or areas with conservation /heritage value. Soil: some soil properties are prioritised over others (e.g. Coarse-textured soils can potentially benefit most from biochar application. may also improve soil ph and soil Organic etc. )? Examples of constructing Criteria as maps arable cereals Major roads (Motor way, Primary route and A road)?

12 with economic variables only arable cereals grassland horticulture MCA roads Least suitable Urban areas Rural settlements woodland Most suitable? with economic variables only MCA with economic variables only Combined Environmental variables Potential sites - (After masking/ constraining it) VALUE=>8(most suitable ones)?

13 Organic carbon II (work-in progress): inclusion of soil variables Soil texture Cation exchange capacity Nitrate vulnerable zones structure + + Rooting depth most suitable least suitable? Further extension of the (work in progress) Economic economic variables + soil variables(with equal weighting between the groups) environmental constraints composite - (After masking/ constraining it) + Soil most suitable most suitable least suitable least suitable?

14 Most suitable areas (using soil variables overlaid with potential sites resultant from earlier )? Network catchment areas of the potential sites?

15 Plans in future The BIAM framework at its current form intends to generate headline figures but also provides key pointers and tools to make more detailed case studies /scenarios for PBS implementation at different scales to find viable niches where biochar can be fitted sustainably. Extend the BIAM framework to our EU participants in Interreg and later to other developing countries Make it replicable Thank you for your attention. Any questions?