هزینه های معاملات از پروژه کربن افست: یک مطالعه مقایسه ای

The land-use change and forestry sector can be a cost-effective contributor to climate mitigation in at least three ways: providing carbon offsets through carbon sequestration in biomass and soils, reducing emissions of methane and other greenhouse gases, and producing biofuels that replace fossil fuels. The presence of carbon markets should help encourage these activities; however, most carbon trades to date have occurred in the energy sector. A major obstacle to carbon trades from land-use systems is the presence of high transaction costs of converting a carbon offset into a tradable commodity, so the prevailing market carbon prices may not provide enough incentive for adoption. This paper presents a model of the exchange of carbon offsets between a project developer and a group of landholders. The model is solved to derive project feasibility frontiers that show the minimum number of contracts necessary to make a project feasible at any given carbon price. The model is applied to two case studies (smallholder agroforestry in Indonesia and partial reforestation of family farms in Australia) under two types of contract (purchase of carbon flows and rental of carbon stocks). The paper concludes by identifying possible strategies to reduce transaction costs while maintaining project integrity.

Globally, land management is one of the most important determinants of environmental outcomes, with impacts on global environmental goods such as climate mitigation, biodiversity conservation and watershed protection. Agriculture, including its impact on land use change accounts for approximately one third of global greenhouse gas emissions (FAO, 2011 and Smith et al., 2007). Environmental policy makers thus face the challenge of providing incentives to landholders to take actions that are beneficial to the environment and which generally involve costs in the form of investment, operating, opportunity or transaction costs. There is a range of environmental policy instruments to promote incentives for change, from command and control regulations to market-based incentive schemes. The distribution of costs and who bears them varies by policy instrument and location (FAO, 2007). Since globally the majority of land managers are low-income, smallholder producers with limited capacity to bear the costs of environmental regulations, considerable interest in the use of payments for environmental services that reward land managers for the provision of positive externalities has arisen (Wunder et al., 2008 and Zilberman et al., 2008). In such schemes, the costs of environmental regulation are principally borne by the consumers of the environmental service. Nonetheless participation in such schemes involves costs to land managers in the form of opportunity and transactions costs. The opportunity cost to landholders participating is normally the income foregone by adopting a particular land use that may be sustainable but less profitable, in present-value terms, than current land uses. Transactions costs associated with contracting, monitoring, reporting and verification of the environmental service provision can also be quite high—particularly the start-up costs of search and negotiation. Wunder et al. (2008) identified projects with start-up costs ranging from $76 to over $4000 per hectare, with strong economies of scale.

There is strong agreement in the literature that transaction costs of search, negotiation, monitoring and enforcement can place significant barriers to implementation of environmental policies. This study was motivated by the dearth of quantitative analysis in this research area, particularly for policies that rely on payments to landholders for environmental services. Our model considers a contract between an aggregator (the Buyer) who buys carbon offsets to sell them in the international market, and a group of landholders (the Sellers) who produce these offsets through changes in their land management practices. The economic conditions for participation of both parties are used to derive a project feasibility frontier (PFF). The PFF indicates the minimum land area (or the number of contracts) required for the aggregator to break even at any given carbon price.