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Tools for optimal coordination of CCS, power industry capacity expansion and bio energy raw material production and harvesting Peter Lohmander Prof. Dr. SLU Sweden [email protected] 2nd Annual EMISSIONS REDUCTION FORUM: Establishing Effective CO2, NOx, SOx Mitigation Strategies for the Power Industry, Marcus Evans, 29th & 30th September 2008, Madrid, Spain Abstract (Peter Lohmander, Madrid 2008) • If we plan the future carbon capture and storage strategy, the power industry capacity expansion and bio energy raw material production and harvesting separately, we will never reach the best possible solution. • Alternative approaches to the optimal coordination problem are presented. • A new continuous time optimal control model is described and analyzed. • The optimal time path of resource extraction is explicitly determined as a function of time dependent CO2 storage revenues and other relevant parameters, including the time dependent parameters of the energy demand function. e-mail: [email protected] References: http://www.lohmander.com/Information/Ref.htm Software: http://www.lohmander.com/Program/Program.htm Conferences: http://www.lohmander.com/Kurser/Kurser.htm • If we plan the future carbon capture and storage strategy, the power industry capacity expansion and bio energy raw material production and harvesting separately, we will never reach the best possible solution. • We may, with alternative definitions and methods, investigate the system that includes the three ”sectors” Forestry (F), the Forest Products Industry (FPI) and the Forest Raw Material Based Energy Industry (FRMBEI). • The ambition is to find the dynamic strategy for the management of this system that leads to the best possible total economic surplus (present value), when we simultaneously consider the CO2 issue. The ”Small Unit Raw Material Perspective” and Optimization • You may instantly calculate the economically optimal decisions, from a ”small unit raw material perspective”, using software available from the Internet: • http://www.lohmander.com/program/Faust_Slut/InFaust3.html • http://www.lohmander.com/program/Stump02/InStump022.html Present Value (SEK/Hectare) Number of Years from the Present Figure 1. The Present Value EXP(- 0.03·t)·(20000 + 1000·t + 2000) Web Software for Economic Optimization from a Raw Material Perspective = Stock level = Growth = Net Price = Net Price Growth = Land Value = Interest Rate(%) Optimize! Optimal Results Optimal Harvest Year Optimal Present Value 250 200 150 A large part of the forest is much older than the economically optimal harvest age 100 50 0 02 310 11 -2 0 21 -3 0 31 -4 0 41 -5 0 51 -6 0 61 -7 0 71 -8 0 81 -9 91 0 -1 10 00 11 12 20 11 14 40 116 0 16 1- tusentals hektar Åldersklassfördelning i Gävleborgs län (perioden 2001-2005) Åldersklass (år) Age distribution in the county of Gävleborg (2001-2005). Thousands of hectares in different age classes (years). • If we invest in CO2 capture and storage technology (CCS) in the energy industry, it is even more important to rapidly harvest the old forest stands! • Then, if we increase the area that is replanted with more rapidly growing trees, we will absorb more CO2 from the atmosphere, separate it and store it permanently. http://www.lohmander.com/co2ill2/co2ill2.htm • A growing forest captures and stores CO2 from the atmosphere. • However, trees do not grow for ever. • Sooner or later, the growth level is reduced, because the age of the trees becomes too high and the competition between neighbour trees too strong for continued growth. • Furthermore, at some age, trees die, and once again release the stored CO2 to the atmosphere. • The total amount of CO2 that may be captured from the atmosphere and permanently stored is much higher if we, in a repeated sequence, harvest the forest, use some part of the biomass for instant energy production, capture and store the CO2 and replant the area again. • With repeated harvesting an CCS, we may, in the long run capture and store any amount of CO2 from the atmosphere! • We do not only reduce the new emissions of CO2 but we really make sure that the CO2 level of the atmosphere is reduced! • If you just leave the forest for ever, without harvesting, you will never be able to store more than what you find in an old forest stand. General continuous time optimal control model of a forest resource, comparative dynamics and CO2 storage consideration effects Economic Valuation of the Production of Energy and Other Industrial Products Economic valuation of CO2 storage in the natural resource t2 rt 2 max J e f1 f 2t x k1 k2t u k3u dt t1 The Total Economic Result (Present Value) The Stock Level The ”Control” Level x f ( x, u, t ) ; x(t1 ) x1 , x(t2 ) x2 Initial stock level The change of the stock level during a marginal time interval Terminal stock level Lohmander, P., Optimal resource control model & General continuous time optimal control model of a forest resource, comparative dynamics and CO2 consideration effects, Seminar at SLU, Umea, Sweden, 2008-09-18 http://www.lohmander.com/CM/CMLohmander.ppt Software: http://www.lohmander.com/CM/CM.htm t2 rt 2 max J e f1 f 2t x k1 k2t u k3u dt t1 x g0 g1 x g 2t u x(t1 ) x1; x(t2 ) x2 Optimal strategy and dynamic effects of the rate of interest Optimal Objective Function Values 1800 Objective Value (Relevant Currency) 1600 1400 1200 1000 800 600 400 200 0 J_3% J_5% Alternative J_7% Optimal Stock Path 3500 Optimal Stock (Mm3sk) 3000 2500 2000 x_3% x_5% 1500 x_7% 1000 500 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Control Path 160 140 Optimal Control (Mm3sk) 120 100 u_3% 80 u_5% u_7% 60 40 20 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Shadow Price Path 250 Shadow Price (Relevant Currency) 200 150 SP_3% SP_5% SP_7% 100 50 0 0 5 10 15 20 Tim e (Years) 25 30 35 Comparisions with alternatives that are not optimal: 30 N1 e .05t 1000 3*106106 dt 6 1.123229489·10 0 30 N2 e 0 .05t 1000 3*86 86 dt 9.914723644·10 5 Optimal strategy and dynamic effects of the slope of the demand function Optimal Stock Path 3500 Optimal Stock (Mm3sk) 3000 2500 2000 x_-4 x_-3 1500 x_-2 1000 500 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Control Path 200 180 Optimal Control (Mm3sk) 160 140 120 u_-4 100 u_-3 u_-2 80 60 40 20 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Shadow Price Path 300 Shadow Price (Relevant Currency) 250 200 SP_-4 150 SP_-3 SP_-2 100 50 0 0 5 10 15 20 Tim e (Years) 25 30 35 Comparisions with two alternatives: 30 N3 e.05t 1000 2*106 106 dt 1.297807679·106 0 30 N4 e.05t 1000 2*(181 5* t ) (181 5* t ) dt 1.397224592·106 0 Optimal strategy and dynamic effects of the terminal condition Optimal Objective Function Values 1240 Objective Value (Relevant Currency) 1220 1200 1180 1160 1140 1120 1100 J_2500 J_2800 Alternative J_3100 Optimal Stock Path 3500 Optimal Stock (Mm3sk) 3000 2500 2000 x_3100 x_2500 1500 x_2800 1000 500 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Control Path 160 140 Optimal Control (Mm3sk) 120 100 u_3100 80 u_2500 u_2800 60 40 20 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Shadow Price Path 250 Shadow Price (Relevant Currency) 200 150 SP_3100 SP_2500 SP_2800 100 50 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal strategy and dynamic effects of continuous stock level valuation, for instance because we want to reward the storage of CO2 Optimal Objective Function Values 1800 Objective Value (Relevant Currency) 1600 1400 1200 1000 800 600 400 200 0 J_f1=0 J_f1=5 Alternative J_f1=10 Optimal Stock Path 3500 Optimal Stock (Mm3sk) 3000 2500 2000 x_f1=5 x_f1=0 1500 x_f1=10 1000 500 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Control Path 160 140 Optimal Control (Mm3sk) 120 100 u_f1=5 80 u_f1=0 u_f1=10 60 40 20 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Shadow Price Path 300 Shadow Price (Relevant Currency) 250 200 SP_f1=5 150 SP_f1=0 SP_f1=10 100 50 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal strategy and dynamic effects of continuous stock level valuation in combination with variations of the the slope of the demand function Optimal Objective Function Values Objective Value (Relevant Currency) 2500 2000 1500 1000 500 0 J_f_-3 J_f_-2.3 Alternative J_f_-1.6 Optimal Stock Path 3500 Optimal Stock (Mm3sk) 3000 2500 2000 x_f_-2.3 x_f_-3 1500 x_f_-1.6 1000 500 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Control Path 200 180 Optimal Control (Mm3sk) 160 140 120 u_f_-2.3 100 u_f_-3 u_f_-1.6 80 60 40 20 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Shadow Price Path 500 Shadow Price (Relevant Currency) 450 400 350 300 SP_f_-2.3 250 SP_f_-3 SP_f_-1.6 200 150 100 50 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal strategy and dynamic effects of the growth function Optimal Objective Function Values 1250 Objective Value (Relevant Currency) 1245 1240 1235 1230 1225 1220 1215 1210 1205 1200 J_-.01 J_.001 Alternative J_.01 Optimal Stock Path 3500 Optimal Stock (Mm3sk) 3000 2500 2000 x_.001 x_.01 1500 x_-.01 1000 500 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Control Path 180 160 Optimal Control (Mm3sk) 140 120 u_.001 100 u_.01 80 u_-.01 60 40 20 0 0 5 10 15 20 Tim e (Years) 25 30 35 Optimal Shadow Price Path 160 Shadow Price (Relevant Currency) 140 120 100 SP_.001 80 SP_.01 SP_-.01 60 40 20 0 0 5 10 15 20 Tim e (Years) 25 30 35 Total perspective I Viirkesförrådets utveckling senda 1920-talet. Alla ägoslag 1 Trend for total standing volume since 1920, all land-use 1 Stock 3500 V0 Milj m3sk 3000 Döda träd Dead or windthrown trees 2500 Lövträd Broad-leaved 2000 Gran Norway spruce 1500 1000 Tall Scots pine 500 Time 19 96 19 86 19 76 19 66 19 56 19 46 19 36 19 26 0 år year 0 1 Exkl. fjäll, fridlyst mark, militära impediment, bebyggd mark samt söt- och saltvatten. Excl. high mountains, restricted military areas, urban land and water surfaces. Milj. M3sk Millions cubic metre standing volume (stem volume over bark from stump to tip) h0 < g h1 > g h2 = g t1 t2 max z0 h0 e dt z1h1e dt z2 h2e dt h1 0 rt t1 rt t2 rt t1 t2 max z0 h0 e dt z1h1e dt z2 h2e dt h1 rt 0 V0 3000 V1 V0 ( g h0 )t1 V ? h1 ? (V1 V ) t2 t1 (h1 g ) t1 rt t2 rt Derivations and parameters (I) Rate of interest r 0,06 Growth (now) Growth (future) g g t1 v0 106 106 5 3000 h0 z0 z1 86 1 1 z2 1 Stock (now) Harvest (before t1) Web software for Total Perspective I http://www.lohmander.com/EF2008/EF2008.htm Report (in Swedish) with appendix (in English) describing Total Perspective I and II http://www.lohmander.com/EF2008/EF2008Lohmander.pdf vfuture h1 t2 totval 3000 106 inf 1680 3000 108 55 1703 3000 110 30 1718 3000 112 21,6 1727 3000 114 17,5 1732 3000 116 15 1735 Observations • Even if we do not accept to decrease the stock level below the very high level of today, we should strongly increase harvesting during a considerable time interval. • In this first derivation, the improved growth rate in new plantations has not been considered. vfuture h1 t2 totval 2500 106 inf 1680 2500 116 65 1800 2500 126 35 1886 2500 136 25 1939 2500 146 20 1973 2500 156 17 1997 Observations • If we are prepared to adjust the stock level to the stock level of the year 1985, (approximately 2 500 Mm3sk), we should increase harvesting very much during a long time period. • Then, the total economic value strongly improves. • In this derivation, the improved growth rate in new plantations has not been considered. Total perspective II If harvested areas are replanted with more rapidly growing seedlings, the stock path becomes strictly convex (during time periods with constant harvesting) t1 V1 V0 ((1 s0t ) g0 s0tg1 )dt h0t1 0 t1 t1 0 0 V1 V0 g 0 dt s0 ( g1 g 0 )t dt h0t1 s0 ( g1 g 0 )t V1 V0 g 0t1 h0t1 2 2 1 Derivations and parameters (II) Rate of interest r 0,06 Growth (now) Growth (new seedlings) g0 g1 t1 v0 106 126 5 3000 h0 z0 z1 86 1 1 z2 ATKvot 1 80 Stock (now) Harvest (before t1) Web software for Total Perspective II http://www.lohmander.com/EF2008/EFchange2008.htm h1 t2 totval vfuture 116 65 1806 3055 126 35 1906 2666 136 25 1966 2586 146 20 2004 2556 156 17 2029 2541 Conclusions • If we plan the future carbon capture and storage strategy, the power industry capacity expansion and bio energy raw material production and harvesting separately, we will never reach the best possible solution. • The presented tools may be used to determine what should be done. • Peter Lohmander is organizing the conference stream “Optimal Forest Management with Increasing Bioenergy Demand” within The 23rd European Conference on Operational Research (EURO XXIII), July 5-8, 2009, Bonn, Germany. http://www.lohmander.com/Bonn2009/Bonn2009.pdf • Let us continue our discussions and meet there! My warmest ”Thanks” to E.ON Sweden for economic support to the project ”Economic forest production with consideration of the forest- and energy- industries”! Peter Lohmander Professor of Forest Management and Economic Optimization, Swedish University of Agricultural Sciences http://www.Lohmander.com [email protected]