Exchange and Study Economic Valuation of Water Resources 中国水利水电科学研究院 China Institute of Water Resources & Hydropower Research (IWHR) 2006 . 11. 17
Outline汇报提纲 Theory Method理论方法 Application实践应用
水资源价值评估途径 Ways to water valuation 可通过环境经济学对环境资源价值(效益/损害)的估算方法进行评估。 环境经济学对环境资源价值的评估通常是通过分析环境的各种功能以及每种功能对人类的满足程度(效用贡献)来获得的。 通过一定的技术方法与手段,水资源的价值最终可通过因水的质和量的变化对人类社会发展的所提供的物品或服务进行定量评估影响来加以评判和体现。
水资源价值的根源(本质) 根据水资源的价值贡献,主要可通过以下几个方面加以确认。 1、具有节约劳动与投入的价值(经济价值) 如水势能转化为水能发电,节约劳动,减少社会经济投入,创造财富。 2、具有形成、维持和恢复劳动的价值(社会价值) 水是生命之源,阳光、空气、水是孕育人类的基础,缺一不可。水是组成生命物质的主要成分,最原始的生命细胞在水中形成。水是劳动力力量的源泉,是人类生命体主要构成成分。缺水对人体的伤害大于缺少食物对人体的伤害。水能补充能量和维持生命正常的新陈代谢,是维持和恢复劳动力最重要的要素之一。 3、具有提供劳动再生的物质基础价值(有机物质形成-生态价值) 合成有机物离不开水,人类赖以生存的有机物都是以水为媒介或直接合成成分而形成的。水维持自然生产力的最重要因素之一。 4、具有提高劳动效率的精神支持价值(环境价值) 水能调节气候、净化空气、美化环境,清新洁净的环境空间带来人们视觉感观上的愉悦与快乐,消除疲劳,舒缓紧张情绪,提高劳动生产效率。
自然资源价值评估方法 分类 直接市场评价法 market valuation for physical effects 揭示偏好价值评估法 revealed preference approach 陈述偏好法 Stated Preference Act 计 量 方 法 剂量—反应法 dose- response technique 损害函数法 生产函数法Changes in productivity or effect on production approach 人力资本法cost of illness approach ,human capital approach 机会成本法opportunity cost 重置成本法replacement cost approach 内涵资产定价法(隐含在产品中,如不同地理位置的房产) 工资差额法/内涵工资价值法 旅行费用法travel cost approach 防护支出法preventive expenditure approach 意愿调查评估法 contingent valuation
环境影响及其价值评估技术选择 环境影响 评价技术选择 生产力 直接市场价值评估法 防护支出法 重置成本法 机会成本法 健康影响 人力资本法 疾病费用法 意愿调查价值评估法 舒适性 旅行费用法 内涵资产价值法 存在价值
1. Theory Method理论方法 1.1 Duality theory of linear programming 线性规划对偶理论法 1.2 Opportunity cost 机会成本法 1.3 Alternative cost 替代费用法 1.4 Cost decomposition 成本分解法 1.5 Equilibrium market price 市场均衡价格法 支付意愿法、存在价值法等其它分析方法
1. Theory Method理论方法 Economic value of water resources refers to incremental benefit, measured with currency, brought by unit natural water (raw water without processing as for commodity) to economic and social users. 水资源经济价值: 每单位原水给经济社会使用者带来的、以现行货币衡量的利益增值。 Real value of water resources can not be directly observed from the market. There are several methods to evaluate the value of water resources
1.1 Duality theory of linear programming 线性规划对偶理论法 The price is calculated aiming at maximum economic benefit. The shadow price calculated reflects consumption of social labour, extent of shortage of resources and price of resources. 以资源有限性为出发点,将资源充分合理分配并有效利用作为核心,以最大经济效益为目标的一种价格测算。反映社会劳动消耗、资源稀缺程度及资源价格。
1.1 Duality theory of linear programming 线性规划对偶理论法 The shortcoming : difficulty in obtaining all the data to derive parameters of the model, the price may not represent real value of water resources themselves and the shadow price derived by the model is static 缺陷:难以全面准确地获得模型涉及的所有相关参数的全部信息,由此确定的价格不一定能真实代表水资源本身的价值,且模型求解的影子价格也是静态的。
1.2 Opportunity cost 机会成本法 Opportunity cost of resources occupied, expressed as maximum marginal benefit obtained from unit resources by giving up other opportunities of gains. Theory of land rent is considered as methodology of opportunity cost for calculating shadow price of water resources. This approach has advantage of straightforwardness and easy access to data, but disadvantage of poor representativeness. 机会成本法 通过资源占用的机会成本来反映水资源的影子价格,以放弃的各类收益机会中单位资源所获得的最大边际收益表征。 地租理论即是计算水资源影子价格的机会成本方法。 该方法较直观,易取得数据,但代表性不一定好。
Combination of the rent theory and production price method 地租理论与生产价格理论结合(李金昌,1995) P— t annual water price,t=1,2,3…….n; i—The average interest rate; R0—Basic rent α—the coefficient representing abundance and the condition of natural resources use, Differential rent; C—Fixed capital value;V—Variable cost;m—Average profit; Qd—Water demand ;Qs—Water supply; Ed—Elasticity of water demand;Es—Elasticity of water supply。 The principle, the complete production cost = cost + profit + land rent practical application, the parameter is difficult to decide. The rent to reflect natural value of resource, the production price reflects the production inputs, the elasticity of supply and demand reflects the degree of water scarcity.
1.3 Alternative cost 替代费用法 Data which reflect cost or function of reproduction of water resources are applied to substitute the shadow price of water resources approximately. recovery cost (reproduction cost or re-procurement cost, cost of wastewater treatment or dam construction, for example) loss due to water shortage (damage function). This approach has advantage of straightforwardness and easy access to data but disadvantage of possible distortion from real shadow price of water resources. 替代费用法 运用可以反映水资源“再生产”成本或作用的其它途径和信息近似替代水资源的影子价格。 恢复代价法(再生产费用,重置成本法,如以污水处理成本或修建蓄水、引水工程的代价表示),缺水损失法(损害函数法)。 该方法较直观,数据易取得,但可能与真正的水资源影子价格存在较大的偏差。
1.4 Cost decomposition 成本分解法 Based on the assumption of an equilibrium market, unit production cost and average profit of commodity water are deducted from market price of the commodity water by applying method of inverse calculation, that is, residual method. Reliability of the result of this approach depends on rationality of the market price. 成本分解法 假设在市场均衡状态下,以商品水的市场价格减去商品水的单位生产成本及平均利润获得,采用逆算(倒推)法。 该方法简单易行,但取决于市场价格的合理性。
1.4 Cost decomposition 成本分解法 要素
1.4 Cost decomposition 成本分解法 Assume: Factors are owned by different investors (设各种生产要素由不同的投资主体拥有) Input of factors Xi : Every production factor is converted into money value in a consistent way according to purchaser price (i.e., determined by the production processes of the factor in the last time interval), i=1,2,…,n。 生产要素投入:按购买者价格(即由提供该类生产要素上一时段的生产过程决定)统一折算为货币量值,以Xi 表示,i=1,2,…,n。
1.4 Cost decomposition 成本分解法 The net return B =T+S 净收益B= T+S ,利税总额 。 The total output Y= ,as the result of sales price (it is not same time as input) multiplied by the quantity of product. 总产出:出售价格(由本时段生产过程决定)与生产产品数量的乘积
1.4 Cost decomposition成本分解法 —— Equation计算公式 The equation of reasonable calculation: the total economic value of water TVW (总的水经济价值) k-water(水要素) the net return rate of costs- “r”(净收益率) r-total of water used(供水量)
1.5 Equilibrium market price 市场均衡价格法 Developing equations of commodity and resource demands and commodity and resource supplies, relative prices of commodities and productions/consumptions of sectors in the study area are simulated under the condition of equilibrium economy. 市场均衡价格法 通过建立商品需求方程,资源需求方程和商品供给方程以及资源供给方程,模拟计算区域经济在一般均衡条件下各部门商品的相对价格 模型所要求的资料数据庞大,收集和处理资料十分困难。是静态的资源配置模型,有极为严峻的假设条件才能成立,现实中往往并不存在,实践应用困难。
2. Application实践应用 In China, approaches used commonly alternative source, loss caused by industrial water shortage, loss caused agricultural water shortage, identical return rate, benefit-sharing coefficient , shadow price. 我国供水效益的计算通常采用的方法: 等效替代工程法,工业缺水损失法,农业缺水损失法,相同收益率法,分摊系数法,影子水价法。 (《水利建设项目经济评价规范》,1996年) Of all the approaches, benefit-sharing coefficient has been extensively applied In late 1980s, this approach was applied for benefit calculations of urban water supplies and irrigation
Approach of Benefit-sharing Coefficient 效益分摊系数法 Principle: profit-sharing of stock. The benefit of industrial production is shared by each of production factor according to its proportion of input based on the principle of ‘Who gets return if he inputs’. 原理:股份分红,按照各部门的投入比例和“谁投入谁受益”的原则对工业生产效益进行分摊。 Assumption (假设条件): (1)All the input factors are reflected in the form of currency in the total input in the production process. 生产过程中所有的投入要素都以货币形式在核计的总投入中得以反映; (2)Input to water supply project is assessed according to shadow price of the input factors. 供水工程投入:按照投入要素影子价格核计; (3)The water supply project is the optimal alternative.工程投资方案:经过方案比选的优化结果。
Approach of Benefit-sharing Coefficient 效益分摊系数法 Foundation:should reflect effect and contribution of whole water source to user。 原则:体现水源对用户的作用和贡献。 Ways(途径): ① proportion of investment, ② proportion of fixed assets, ③ proportion of cost, ④ proportion of fund occupied (including fixed fund floating fund) or ⑤ proportion of discounted annual cost. ①投资比例法 ②固定资产比例法 ③成本比例法,④占用资金(包括固定资金与流动资金)比例法,⑤折算年费用(投资与年运行费的折算年值)比例法。 The methods of proportion investment and proportion of fixed assets are commonly used because of easy access to data and simple calculation. 在实际工作中,广泛采用① ②两种(资料易于收集并计算较为简便)。
Approach of Benefit-sharing Coefficient 效益分摊系数法 Equation(计算公式) 水源工程全部固定资产原值与所有使用该水源的用水部门固定资产原之和的比例 ε= original fixed assets value of water project / (original fixed assets value of water project + original fixed assets value of production sector)
其它评价方法 市场评价法 恢复代价法 根据水的服务(经济、生态)功能,分析缺水造成经济或环境的损失评估水的价值。 通过观察市场中其他活动过程中类似的服务或产品的市场价格加以评估和换算。(类比) 恢复代价法 地表水:污水处理费用(替代成本) 地下水:回灌工程费用,地面损失(以控制地下水超采减少的经济损失表示 )
谢 谢!