The 2000 Billion Ton Carbon Gorilla Implication of terrestrial carbon emissions for a LCS Global Energy Technology Strategy Program Low Carbon Society Marshall Wise, Leon Clarke, Kate Calvin, Allison Thomson, Ben Bond- Lamberty, Ron Sands, Steve Smith, Tony Janetos, Jae Edmonds February 12, 2009 PNNL-SA-60765
I ntroduction There are approximately 2000 PgC in the terrestrial ecosystem. All human activities must be limited to about 500 PgC (2005 to 2095) to limit atmospheric CO 2 to 450 ppm Terrestrial systems cannot be ignored in the development of a strategy to achieve an LCS. We find that relative to a reference scenario, a larger stock of unmanaged ecosystems and managed forests is desirable to limit carbon concentrations consistent w ith a Low Carbon Society. 2
Agriculture and Bioenergy Assum ptions Bioenergy can be an important technology to implement the goals of a Low Carbon Society Three types of bioenergy 1. Traditional—treated exogenously 2. Co-products, e.g. bark and waste in pulp and paper, but also crop residues, Depend on production of the primary product. � Have a price-sensitive availability curve. � 3. Purpose-grown bioenergy crops—high productivity cellulosic bioenergy crops— not corn . Agricultural crop productivity growth rates Reference scenario—productivity growth declines to ~0.25%/yr by 2050 everywhere. 3
Reference Scenario Bioenergy— dom inated by crop residues and m unicipal w aste 120 Bioenergy Production 100 80 Purpose Grown EJ/yr 60 Bioenergy Municipal Solid Waste 40 Crop Residue 20 Derived Bioenergy 0 1990 2005 2020 2035 2050 2065 2080 2095 4
Crop Productivity as a Clim ate Technology 5
How im portant is the realized crop productivity grow th rate? Continued crop productivity growth is as important as many energy technologies—larger in aggregate than a Pacala-Socolow “Wedge”. We re-run the reference scenario with a fixed crop productivity assumption and compare to the reference scenario which assumes that crop productivity converges to 0.25%/yr in 2050. We then compare the four scenarios in terms of land-use, crop prices, land-use change emissions, and bioenergy production. 6
Land Use Change Em issions and Crop Productivity 3,000 Land Use Change Emissions Cumulative 2,500 Emissions 2005 to 2095 2,000 0.5%/yr crop productivity growth: 1,500 50 PgC 1,000 TgC/yr No crop productivity growth: 500 122 PgC 0 2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100 Difference -500 72 PgC -1,000 0.25%/yr Crop Productivity Growth No Crop Productivity Improvement -1,500 7
Context of Clim ate Bioenergy in the Stabilization 8
Lim iting Atm ospheric CO 2 Concentrations We examine scenarios with the CO 2 concentration limited to 450, 500 and 550 ppm at the end of the century. The choice is arbitrary and is used solely for illustrative purposes. This choice should not be interpreted to reflect any belief that these concentration limits are inherently superior to any other CO 2 concentration limits. 9
Carbon Pricing Tw o alternative carbon pricing regimes Fossil fuel and industrial carbon tax (FFICT) —in this 1. regime only fossil fuel and industrial carbon emissions are valued. Bioenergy is treated as having no net carbon. Terrestrial carbon is valued at zero . 2. Universal carbon tax (UCT) —in this regime all carbon is valued equally regardless of either its origins or the activity that introduces it to (or removes it from) the atmosphere. 10
Em issions, Concentrations and Stabilization—UCT Scenarios Total Anthropogenic CO 2 Atmospheric CO 2 Emissions Concentrations 800 25,000 Reference 550 UCT 500 UCT 450 UCT 550 FFICT 500 FFICT 700 450 FFICT 20,000 600 15,000 500 TgC/yr PPM 400 10,000 UCT 550 ppm 300 UCT 500 ppm 5,000 UCT 450 ppm Reference 200 FFICT 550 ppm FFICT 500 ppm 0 FFICT 450 ppm 100 2005 2020 2035 2050 2065 2080 2095 0 -5,000 2005 2020 2035 2050 2065 2080 2095 Note: All scenarios are “overshoot”. 11
Net Land Use Change Em issions & Fossil Fuel and I ndustrial CO 2 Em issions—W hen All Carbon is Valued ( UCT) For a given CO 2 concentration limit � Valuing carbon suppresses land use change emissions. � Valuing carbon also increases fossil fuel and industrial emissions 25,000 25,000 Fossil Fue l a nd Industria l CO 2 Land Use Change Emissions Reference 550 UCT 550 UCT 20,000 20,000 500 UCT 500 UCT 450 UCT 450 UCT 550 FFICT Reference 500 FFICT 15,000 15,000 550 FFICT 450 FFICT 500 FFICT 450 FFICT TgC/yr TgC/yr 10,000 10,000 5,000 5,000 0 0 2005 2020 2035 2050 2065 2080 2095 2005 2020 2035 2050 2065 2080 2095 -5,000 -5,000 12
Carbon Price & Bioenergy W hen Terrestrial Carbon is NOT Valued ( FFI CT) Valuing all carbon, including terrestrial carbon � Dramatically reduces the price of carbon. � Cuts the price at 450 ppm in half! � Reduces the amount of bioenergy production in the long term, but increases near-term bioenergy supply, relative to the case in which terrestrial carbon was not valued. 200 $3,500 Carbon Price Purpose Grow n Bioenergy 180 UCT 550 $3,000 550 UCT UCT 500 160 500 UCT UCT 450 450 UCT Reference $2,500 Reference 140 550 FFICT 550 FFICT 500 FFICT 500 FFICT 450 FFICT 120 2005 USD/tC 450 FFICT $2,000 EJ/yr 100 $1,500 80 60 $1,000 40 $500 20 0 $0 2005 2020 2035 2050 2065 2080 2095 2005 2020 2035 2050 2065 2080 2095 13
300 Reference Bioenergy Use: FFI CT and UCT 5 0 0 250 biomass to H2 biomass to H2 CCS Biomass (IGCC)_CCS ppm Scenarios Biomass (IGCC) Biomass (existing) 200 Biomass (conv) refined liquids industrial refined liquids enduse wholesale gas industry EJ/yr building 150 100 � SUBSTANTIALLY LESS BIOENERGY 50 PRODUCTION OCCURS THAN WHEN TERRESTRIAL CARBON IS NOT VALUED. 0 2005 2020 2035 2050 2065 2080 2095 � Most bioenergy still goes to electricity production with CCS in the concentration limit scenarios. FFICT 500 ppm UCT 500 ppm 300 300 250 250 biomass to H2 biomass to H2 biomass to H2 CCS biomass to H2 CCS Biomass (IGCC)_CCS Biomass (IGCC)_CCS Biomass (IGCC) Biomass (IGCC) Biomass (existing) Biomass (existing) 200 Biomass (conv) 200 Biomass (conv) refined liquids industrial refined liquids industrial refined liquids enduse refined liquids enduse wholesale gas wholesale gas industry industry EJ/yr EJ/yr building building 150 150 100 100 50 50 0 0 2005 2020 2035 2050 2065 2080 2095 2005 2020 2035 2050 2065 2080 2095 14
Bioenergy Use Reference UCT Scenarios 300 250 biomass to H2 biomass to H2 CCS Biomass (IGCC)_CCS Biomass (IGCC) Biomass (existing) 200 Biomass (conv) refined liquids industrial refined liquids enduse wholesale gas industry � As the limit tightens, more bioenergy is EJ/yr building 150 shifted tow ard bioelectricity production 100 50 w ith CCS. � Bioenergy supply grows more rapidly as the 0 2005 2020 2035 2050 2065 2080 2095 CO 2 concentration limit tightens, but maximum production remains below 200 EJ/yr . 300 300 300 UCT 450 ppm UCT 500 ppm UCT 550 ppm 250 250 250 biomass to H2 biomass to H2 biomass to H2 biomass to H2 CCS biomass to H2 CCS biomass to H2 CCS Biomass (IGCC)_CCS Biomass (IGCC)_CCS Biomass (IGCC)_CCS Biomass (IGCC) Biomass (IGCC) Biomass (IGCC) Biomass (existing) Biomass (existing) Biomass (existing) 200 200 200 Biomass (conv) Biomass (conv) Biomass (conv) refined liquids industrial refined liquids industrial refined liquids industrial refined liquids enduse refined liquids enduse refined liquids enduse wholesale gas wholesale gas wholesale gas industry industry industry EJ/yr EJ/yr EJ/yr building building building 150 150 150 100 100 100 50 50 50 0 0 0 2005 2020 2035 2050 2065 2080 2095 2005 2020 2035 2050 2065 2080 2095 2005 2020 2035 2050 2065 2080 2095 15
$3,500 Carbon Prices, Crop Carbon Price UCT 550 $3,000 Prices, & Land Use UCT 500 UCT 450 Reference $2,500 550 FFICT Change Em issions 500 FFICT 450 FFICT 2005 USD/tC $2,000 � Carbon prices and land use change emissions $1,500 decline relative to the stabilization scenario $1,000 where terrestrial carbon is not valued. $500 � But, crop prices are even higher, especially in $0 the near term. 2005 2020 2035 2050 2065 2080 2095 12.0 16,000 Land-Use Change Emissions Wheat Price 14,000 550 UCT 550 UCT 10.0 500 UCT 500 UCT 450 UCT 12,000 450 UCT Reference Reference 550 FFICT 500 FFICT 550 FFICT 8.0 10,000 I nde x 2 0 0 5 =1 .0 450 FFICT 500 FFICT 450 FFICT 8,000 TgC/yr 6.0 6,000 4.0 4,000 2,000 2.0 0 2005 2020 2035 2050 2065 2080 2095 0.0 -2,000 2005 2020 2035 2050 2065 2080 2095 16
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