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Environment and Natural Resource Economics Course

Environment and Natural Resource Economics Course. Nanjing Agriculture University September 4 to September 30, 2006 Lecturers: Volker Beckmann, Humboldt University Max Spoor, ISS, The Hague Justus Wesseler, Wageningen University. Lecture 4. Environmental Cost - Benefit - Analysis

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Environment and Natural Resource Economics Course

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  1. Environment and Natural Resource Economics Course Nanjing Agriculture University September 4 to September 30, 2006 Lecturers: Volker Beckmann, Humboldt University Max Spoor, ISS, The Hague Justus Wesseler, Wageningen University

  2. Lecture 4 Environmental Cost - Benefit - Analysis under Irreversibility, Risk, and Uncertainty Lecturer: Dr. Justus Wesseler, Wageningen University

  3. Option Value Value relates to the willingness to pay to guarantee the availability of the services of a good for future use by the individual. Concept was introduced by Weisbrod (1964) in considering a national park and the prospect of its closure. He argued the benefit of keeping the park open would be understated by just measuring current consumer surplus for visitors and that there should be added to that a measure of the benefit of future availability -> called option value.

  4. Option Value (OV) U U(Y) U(A) A C YA-Y*: option price, OP, the maximum amount that the individual would be willing to pay for the option which would guarantee access to an open park. YA-Y**: expected value of the individual’s compensating surplus1), E[CS]. Option value, OV: OP - E[CS]=Y**-Y*. “Option value is a risk aversion premium” (Cicchetti and Freeman, 1971, p.536) N U(N) YN Y* Y** YA Y Figure 13.2 Risk aversion, option price and option value (Perman et al.: page 448) 1) Compensating surplus: WTP for improvement of the environment to happen.

  5. Irreversibilities Examples: loss in biodiversity landscape changes GHG emissions several forms of pollution (pesticides, SO2) sunk investment costs

  6. Irreversibility with future known. A: amenity value of wilderness area MC: marginal costs MB: marginal benefits NB: net benefits MNB: marginal net benefits

  7. Irreversibility with future known. A1: amenity value now, period 1 A2: amenity value in the future, period 2 MNB2 > MNB1 A1NI: MNB1 = 0. A2NI: MNB2 = 0. A2NI > A1NI

  8. Irreversibility with future known. • Considering irreversibility: • Optimal preservation at AI1, AI2 • Cost of irreversibility: • area abc in period 1 • area def in period 2 • Cost of ignoring irreversibility: edhi – abc.

  9. Irreversibility with future unknown. Figure 13.5 Irreversibility and development with imperfect future knowledge (Perman et al.: page 454) MNB known in period 1, unknown in period 2 E[MNB2]=p*MNB21 + (1-p) MNB22 Irreversibility implies: A2 A1 AI1, AI2: outcome where there is irreversibility but no risk. If MNB21, A1NI is chosen. If MNB22, A2I is chosen If uncertainty about MNB2, outcome AI1, AI2, if p = 0.5.

  10. Quasi Option Value. • Notation and assumptions: • D: development, P: preservation, Ri: return from i-th option • Bpt: preservation benefits, Bdt: development benefits • Cdt: development costs, only in the period development project is undertaken • two periods t, 1 now and 2 the future, • benefits, B, and costs, C, in period 2 are in present values (discounted) • DM has complete knowledge of all period 1 conditions • at the start of period 1, period 2 outcomes can be listed and probabilities attached to them • at the end of period 1, complete knowledge about period 2 will become available to the DM • decision to be taken at the start of period 1 is whether to permit development

  11. Quasi Option Value. Two-period development/preservation options. return immediate development: R1 = (Bd1 – Cd1) + Bd2 return preservation in period 1: either R2 or R3

  12. Quasi Option Value. Two-period development/preservation options. • return preservation in period 1: either R2 or R3 (Option 2 or 3) • => if Bp2 > (Bd2 - Cd2) => choose R3, preservation period 2 • returns from preservation in the first period, Rp : Rp = Bp1 + max{Bp2,(Bd2 - Cd2)}

  13. Quasi Option Value. Two-period development/preservation options. assume complete knowledge over future circumstances => develop if Rd > Rp -> Rd - Rp > 0 => (Bd1 - Cd1) + Bd2 - Bp1 - max{Bp2,(Bd2 - Cd2)} > 0 (Bd1 - Cd1) - Bp1 actually known to DM, other terms not, that’s why it is not an operational decision rule

  14. Quasi Option Value. • assume complete knowledge over future circumstances • => develop if Rd > Rp -> Rd - Rp > 0 • => (Bd1 - Cd1) + Bd2 - Bp1 - max{Bp2,(Bd2 - Cd2)} > 0 • (Bd1 - Cd1) - Bp1 actually known to DM, other terms not, that’s why it is not an operational decision rule • Now, assume possibleoutcomes of Bd2, Bp2,(Bd2 - Cd2) are known and DM can assign probabilities to the mutually exclusive outcomes. • => (Bd1 - Cd1) - Bp1 +E[ Bd2] - max{E[Bp2],E[(Bd2 - Cd2)]} > 0 • ignores, more information are available at the start of period 2.

  15. Quasi Option Value. • Now, assume possible outcomes of Bd2, Bp2,(Bd2 - Cd2) are known and DM can assign probabilities to the mutually exclusive outcomes. • => (Bd1 - Cd1) - Bp1 +E[ Bd2] - max{E[Bp2],E[(Bd2 - Cd2)]} > 0 • ignores, more information are available at the start of period 2. • if area is developed in period 1, information cannot be used • if area is preserved in period 1, information can be used whether or not to develop in period 2 • but decision has to be made in period 1, but DM also knows the outcomes and the probabilities

  16. Quasi Option Value. • Now, assume possible outcomes of Bd2, Bp2,(Bd2 - Cd2) are known and DM can assign probabilities to the mutually exclusive outcomes. • => (Bd1 - Cd1) - Bp1 +E[ Bd2] - max{E[Bp2],E[(Bd2 - Cd2)]} > 0 • but decision has to be made in period 1, but DM also knows the outcomes and the probabilities • this leads to the following decision rule, develop if: • Rd = (Bd1 - Cd1) - Bp1 +E[ Bd2] - E[max{ Bp2,(Bd2 - Cd2)}] > 0

  17. Quasi Option Value. Develop if, (considering availability of future information): (Bd1 - Cd1) - Bp1 +E[ Bd2] - E[max{ Bp2,(Bd2 - Cd2)}] > 0 Develop if, (ignoring availability of future information): (Bd1 - Cd1) - Bp1 +E[ Bd2] - max{E[Bp2],E[(Bd2 - Cd2)]} > 0 Quasi option value: E[max{ Bp2,(Bd2 - Cd2)}] - max{E[Bp2],E[(Bd2 - Cd2)]} > 0 The amount by which the net benefits form development project that includes irreversible costs have to be reduced. => reflects the benefits of keeping the option alive for future preservation

  18. Quasi Option Value. Simple numerical example: max{E[Bp2],E[(Bd2 - Cd2)]} = max{E[0.5*10 + 0.5 * 5], E[0.5*6 + 0.5 * 6]} = max {7.5, 6}= 7.5 develop if : (Bd1 - Cd1) - Bp1 +E[ Bd2] - 7.5 > 0 result: 7.75 - 7.5 = 0.25 > 0.

  19. Quasi Option Value. Simple numerical example: • Now consider E[max{ Bp2,(Bd2 - Cd2)}], there are two outcomes • A where Bp2 > (Bd2 - Cd2), Bp2 =10, pA = 0.5 • B where Bp2 < (Bd2 - Cd2), (Bd2 - Cd2)= 6, pB = 0.5 • Hence: E[max{ Bp2,(Bd2 - Cd2)}] = (0.5 * 10) + (0.5 * 6) = 8 • develop if : (Bd1 - Cd1) - Bp1 +E[ Bd2] - 8 > 0 • result: 7.75 - 8.0 = - 0.25 < 0 ! => don’t develop first period

  20. Quasi Option Value. Simple numerical example: QOV= E[max{ Bp2,(Bd2 - Cd2)}] - max{E[Bp2],E[(Bd2 - Cd2)]} = 8 - 7.5 = 0.5. The QOV is always positive, as it allows to reduce losses compared to the situation where the arrival of information is ignored.

  21. The real option approach to cost - benefit - analysis under irreversibility, risk and uncertainty

  22. Introduction

  23. The irreversibility effect: some examples related to the release of herbicide tolerant sugar beets (htSB) • Assumptions: • benefits from non-htSB 1000€/ha, infinite • benefits from htSB 1200€/ha, infinite • scrap value of old sugar beet planter: 500€ • price of a used new sugar beet planter 2100€ • discount rate is 10% • => incremental benefits per hectare: 200€ • => incremental irreversible investment: 1600€

  24. The irreversibility effect: some examples related to the release of herbicide tolerant sugar beets (htSB) Value of adopting htSB: Irreversible investment for htSB: I =1600 NPV of for adopting htSB: V - I = 2000 - 1600 = 400

  25. The irreversibility effect: some examples related to the release of herbicide tolerant sugar beets (htSB) • Introducing uncertainty about future incremental benefits from htSB: • if future looks good, incremental benefits are high, 300€/ha • if future looks bad, incremental benefits are low, 100€/ha • both situations are equally likely, DM is risk neutral • = > the expect value, E[V], of the project:

  26. The irreversibility effect: some examples related to the release of herbicide tolerant sugar beets (htSB) What is the value, V, of adopting htSB, if the future incremental benefits are low? What is the value, V, of adopting htSB, if the future incremental benefits are high?

  27. The irreversibility effect: some examples related to the release of herbicide tolerant sugar beets (htSB) Now, we assume the farmer is flexible and can postpone his decision. Would this provide him with any additional gain? In the case the gross margin: - increases, the NPV one year from now is: or in today’s value: - decreases, the NPV one year from now is: or in today’s value: In the latter case the farmer would not invest. The gain from waiting is the gain from avoiding losses of 545 Euro in present value.

  28. The irreversibility effect: some examples related to the release of herbicide tolerant sugar beets (htSB) The economic gain from waiting can be calculated by comparing the expected value of the immediate investment with the one from waiting one year. The gain from immediate investment is 400 Euro (see before). The gain from from postponed investment is: The economic gain from waiting is the difference between the two, i.e. 236 Euro.

  29. The irreversibility effect: some examples related to the release of herbicide tolerant sugar beets (htSB) At this point it is worthwhile noting the importance of the irreversibility effect. It only pays to wait when the investment costs are irreversible. This observation will be even more obvious if the incremental net-benefit would be negative in the bad case. Then the farmer would immediately stop producing htSB and move back to planting n-htSB. If the initial investment costs were not irreversible, immediate investment would be optimal. Also, it would be optimal to invest immediately, if the investment could not be postponed due to other circumstances, such as a contract for planting htSB only offered once. A third important observation is the opportunity costs of waiting. Waiting pays as the veil of uncertainty will be removed after one year, but at the same time the benefits at the end of year one are foregone. These foregone benefits of expected 200 are the opportunity costs of waiting.

  30. Decision in the presence of irreversible costs and irreversible benefits The benefits that have been discussed, the incremental benefits, are reversible. By stopping planting htSB, incremental benefits are also foregone. => As there are irreversible costs there are also irreversible benefits. => These are benefits that will continue to be present even if the action that has produced them stops. Consider, for example, a one-time subsidy of 500 Euro for planting htSB. The E[NPV0I] increases in this case by exactly 500 Euro and the E[NPV0I] = 900. The E[NPV0P] from waiting in this case is:

  31. Decision in the presence of irreversible costs and irreversible benefits The E[NPV0I] > E[NPV0P] (900 > 864) and there are no gains from waiting. The irreversible benefits reduce the irreversible cost, which leads in this case to an immediate investment. The case of irreversible benefits is similar to the case where the adoption of transgenic crops reduces the use of pesticides harmful to human health.

  32. Decision in the presence of irreversible benefits Another interesting question is the case where irreversible benefits decrease over time. This can be modelled by assuming where the subsidy is in the form of a loan and has to be paid back after ten years. The E[NPV0I] is: The E[NPV0P] is: The E[NPV0I] of an immediate investment in this case is 707 Euro, which is also in this case higher than in the case without the subsidy (636 Euro) and less than in the case with the subsidy as a grant (900 Euro). Although, in this case postponing the investment would be a better decision.

  33. Decision in the presence of irreversible benefits Another interesting questions related to the irreversible benefits is, whether there are gains from waiting if only irreversible benefits and no irreversible costs are present or if the net-irreversibility effect is positive. Under a positive net-irreversibility effect there will be no gains from waiting, as there are no losses that can be avoided. The E[NPV0I] in the case of irreversible benefits only is: The E[NPV0P] in the case of irreversible benefits only is: The E[NPV0I] under this scenario will always be greater than the E[NPV0P] due to the discounting effect and therefore waiting does not provide an economic gain.

  34. Decision in the presence of irreversible benefits The important observations about the irreversible benefits are threefold: 1. irreversible benefits reduce irreversible costs and this by the order of one. One unit of irreversible benefits compensates for one unit of irreversible costs. 2. a decrease in irreversible benefits over time, even up to a hundred percent, still has a positive impact on the value of the project. 3. a positive irreversibility effect does not provide economic gains from waiting.

  35. Decision in the presence of irreversible benefits The Special Case of Pest-Resistance • The susceptibility of pests to control agents is a non-renewable resource => the appearance of pest resistance is an irreversibility. • Biologists and entomologists in particular argue that susceptibility to control agents, pesticides in particular, should be viewed as a renewable resource. That is, if pests become resistant to a control agent and consequently the use of the control agent stops, pest resistance breaks down after a while and pests do become susceptible again. • Question: does an irreversibility effect exists?

  36. Decision in the presence of irreversible benefits The Special Case of Pest-Resistance • To show that an irreversibility effect does indeed exist consider the following hypothetical example for Bt-corn used against damages from the European Corn Borer (ECB): • The incremental benefits from adopting Bt-corn are assumed to be 200 at the beginning, period one, and due to price uncertainty increase to either 300 or 100 after one time period and remain at the level till the end of the fourth period. • At the end of the fourth period the ECB becomes resistant to Bt-corn and the incremental benefits decrease to zero from period five till the end of period seven. • At the end of period seven, the ECB becomes susceptible again to Bt-corn. • To keep the example simple, we assume that the incremental benefits increase to 200 Euro until infinity as the ECB will also be susceptible till infinity. The costs of pest resistance in present value terms are 1600 Euro. These are extra costs beyond the lost incremental benefits of period five, six and seven.

  37. Decision in the presence of irreversible benefits The Special Case of Pest-Resistance 300  200 100 0 1 2 3 4 5 6 7 8 9 10 …  ECB bt susceptible ECB bt resistant ECB bt susceptible Figure: Example for appearance and breakdown of ECB resistance to Bt-toxin.

  38. Decision in the presence of irreversible benefits The Special Case of Pest-Resistance The value of Bt-corn from immediate adoption is: The result for a postponed adoption is: The example illustrates that even though pest resistance can be reversible from a biological point of view, from an economic point of view an irreversibility effect may exist.

  39. Private and Public Irreversibilities Figure. The Two Dimensions of an Ex-Ante Social Benefit-Cost Analysis including irreversibilities

  40. Private and Public Irreversibilities An example: The decision rule to release htSB is formulated as, to release htSB if the net reversible social benefits W, the sum of quadrant 1 and quadrant 2 in figure 2, are greater than the net irreversible costs, the sum of quadrant 3 and quadrant 4, multiplied by a factor greater than one, the so-called hurdle rate : As the social irreversible costs, I=PIC + EIC, and benefits, R=PIB+EIB, of transgenic crops are highly uncertain, instead of identifying the net reversible social benefits W required to release transgenic crops in the environment, the maximum tolerable social irreversible costs I* under given net social reversible benefits W and social irreversible benefits R are identified:

  41. Table. Hurdle Rates and Annual Net Private Reversible Benefits (W), Social Irreversible Benefits (R), and Maximum Tolerable Social Irreversible Costs (I*) per Hectare Transgenic Sugar Beet a sugar beet area-weighted average of the individual Member States’ hurdle rates. b The extreme estimates for Greece, Ireland and Portugal are probably due to data inconsistencies. These countries only cover 4% of total EU sugar beet area, almost not affecting the EU average. c No data on margins has been found for Portugal. We use the EU area-weighted average.

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