OPTIMIZING BIOMASS CONTRIBUTION TO GLOBAL ENERGY BALANCE

Transcription

1 OPTIMIZING BIOMASS CONTRIBUTION TO GLOBAL ENERGY BALANCE EDF Patrice Dhumes François Cattier, Jean-David Sta, Jerôme Wirth EDF R&D International Energy Workshop, Paris June 2013

2 CONTEXT AND OBJECTIVES 3 major Challenges : Under current energy policies, energy needs and associated CO2 emissions are expected to double between now and 2050 Fossil fuel resource scarcity, especially for oil, will intensify Food demand will increase by 70% by 2050 [EC SCAR, 2011] These driving forces will drastically increase the pressure on land use in order to: Respond to the food challenge Develop bioenergy and biofuels in order to compensate at least partly the expected decline of oil resources Preserve some areas for CO2 sequestration or for biodiversity Support urbanization and development in emerging countries The objectives of this work are twofold : evaluate the potential for bioenergies and their roles in the future energy supply, taking into account land use constraints estimate the impacts of land use changes induced by biomass production on CO2 concentration Optimizing Biomass contribution to global energy balance 2

3 SCENARIOS SIMULATION USING MESCALITO A SIMPLE GLOBAL ENERGY MODEL Mescalito major Characteristics : Long term horizon : 2100 The World in 4 regions:eu27, North America, Asia and Rest of World Supply and Demand simulated independently - An equilibrium can be reached by iterations MESCALITO has been enhanced in order to take into account land use constraints and evaluate theirs implications on bioenergy supply and CO2 concentrations Land Use Module Demographic and economic assumptions Biofuels, Solid Biomass, Wastes Agrofuel Potential Food Demand Mescalito Core model Energy Balances CO2 Emissions & concentrations Optimizing Biomass contribution to global energy balance 3

4 MAIN BIOFUEL CARRIERS Primary Products Fuelwood Processes Energy Vectors Fuelwood Forest Residues Non renewable Wastes Charcoal wood products Electricity Renewable & Livestock wastes CHP Methanisation Heat Biomethane H2 Crop Residues Energetic crops Gazification H2 Fischer Tropsch 1G Biofuels Optimizing Biomass contribution to global energy balance 4

5 MAIN MESSAGES FROM THE REFERENCE SCENARIO Global primary energy balance Gtoe Oil Solids Nuclear Biomass Hydro Other Renewables A moderate energy demand growth - calibrated on the WEO NPS and ETP 4DS up to 2050 Due to the decline of oil production after 2020, gas and coal would take an increasing share of the global energy mix Optimizing Biomass contribution to global energy balance 5

6 LAND AVAILABILITY PROJECTIONS Land Areas are divided into 5 categories Projections based on historical trends and macroeconomic variables for Forest, Desert and Built-up land Agricultural area obtained by difference with total land area Total land area Forest Desert and Built-up Global Land Area by type Agriculture Grasslands and Pastures Food crops Energy crops Optimizing Biomass contribution to global energy balance 6

7 SCENARIOS Food diet scenarios provide demand for agricultural products based on Agrimonde study Combined with agricultural productivity assumptions, we obtain demand for food crops and pastures Remaining agricultural areas are supposed available for crops dedicated to energy production A Reference scenario based on current agricultural land and 4 Alternative scenarios The Intensive Scenario, assumes that all available lands (including tundra and wetlands) are progressively used but with a lower productivity The Moderate Scenario, assumes that only the most productive parts of potential agricultural lands are used Two options on biofuel production : Liquids / Food Diet and landuse impact Additional agricultural surface potential Agricultural Productivity Fuel preference Scenarios Agrimonde AG0 Reasonable High Liquid Reference More meat trend Low Liquid Full High Liquid Intensive-Liquid Intensive- Low Liquid Agrimonde AG1 Reasonable High Liquid Less meat Low Liquid Moderate-Liquid Moderate- Full High Liquid Low Liquid Optimizing Biomass contribution to global energy balance 7

8 CROPS AND PASTURE Agricultural Land Area by type and Regions Potential land for agrofuels vary among scenarios Main producers of energy crops are North America and Eastern Europe in the Intensive Scenario and Sub-Saharan Africa and Latin America in the Moderate Scenario Optimizing Biomass contribution to global energy balance 8

9 FROM AVAILABLE AREA TO ENERGY PRODUCTION 9 types of energy crops considered Share of available land allocated to each crops based on FAPRI Scenario up to 2025 and kept constant afterwards Source : FAPRI. Note : biogas productivity based on corn Agrofuel productivity increases in most regions, with most significant growth in Sub- Saharan Africa and Asia Optimizing Biomass contribution to global energy balance 9

10 AGROFUEL POTENTIAL AND BIOMASS ENERGY PRODUCTION The combination of remaining agricultural area and productivity for energy crops (toe/ha) provides agrofuel potential Biomass remains largely consumed in a solid form in the Reference Increase use of agricultural land would at least double the potential of bioenergy Biogas production would be more interesting than liquid biofuel from an energetic point of view Total biomass production represents more than 20% of global energy needs in 2050 Global Biomass production, 2050 Optimizing Biomass contribution to global energy balance 10

11 GLOBAL EMISSIONS FROM FOSSIL FUEL COMBUSTION The contribution of agrofuels is significant but fossil fuels (coal and gas) would still represent the majority of energy supply, leading to significant CO2 emission increases although lower than in the Reference The differences between scenarios are relatively limited due to opposite effects of assumptions on productivity and food diets Optimizing Biomass contribution to global energy balance 11

12 CO2 EMISSIONS FROM LAND USE CHANGE (LUC) CO2 concentration is then estimated using a four box stock-flux model CO2 emissions from fossil fuels are imported from the Mescalito core model Atmosphere (597 Gt) CO2 emissions from land-use change estimated using IPCC Carbon content 120 Gt 120 Gt 70 Gt 70 Gt Land (2300 Gt) Ocean surface (900 Gt) 101 Gt 101 Gt Deep Ocean (37100 Gt) Source : IPCC 2000 and Wetland International (2008) Optimizing Biomass contribution to global energy balance 12

13 CO2 CONCENTRATION Higher CO2 concentration in the Agrofuels Scenarios than in the Reference The negative effects of LUC more than compensate the direct emissions avoided by the development of agrofuels Agrofuels in the Intensive scenario would definitely be less interesting than fossil fuel from a carbon point of view The concentration in the moderate Scenario remains close to those of the Reference, And their benefits would progressively increase after 2050 Optimizing Biomass contribution to global energy balance 13

14 CONCLUSION Key messages : Biomass potential although important remains limited by land availability. In the absence of productivity or food regime breakthrough, liquid biofuels would not be able to replace oil but could reduce fossil fuel dependency Production estimates for biogas are higher than for liquid biofuels, especially in regions where corn productivity is high Globally, biofuels from traditional crops do not appear to be a solution to fight climate change due to emissions from land use change Limits of this exercise : The impact of the development of agrofuels on CO2 emissions depends largely on the types of land mobilized and on their carbon contents. The relative carbon content of croplands and grasslands is a key point in the estimation of agrofuel impact on greenhouse effect CO2 emissions would be worsened if the energy needed to increase land productivity (production of fertilizers ) was taken into account Optimizing Biomass contribution to global energy balance 14