碳排放權通過市場交易實現效率配置,有理論與實踐支撐。"碳排放"作為一種"惡品",需要不斷壓縮或定額管控,與"善品"有著本質不同。因而,"碳排放"市場交易有著固有的困境。在國內碳市場構建中,困境還會得到強化。因為,1中國與國際社會、中央與地方、地方之間、政府與企業存在多重博弈,受經濟、政治、環境、社會多重因素的制約,排放總量的確定和分配具有潛在的不確定性。2"碳"的核算從屬于能源,并不完全獨立,是一種具有被動屬性的交易品,企業的選擇與能效和節能關聯,則"用能權"和"碳排放權"重疊。由于碳作為交易品的從屬和被動屬性,企業的經營決策的碳約束可能被弱化或邊緣化,對消費者的價格信號部分失真。3開放的、競爭的市場才是有效率的。但是從歐盟的碳排放貿易體系和國內的試點看,這一系統則是相對封閉的。4如果說高碳產品低品質可以通過市場的自我調節而對企業有所約束,而城市基礎設施鎖定的碳,其成本只能由全社會擔承,在碳排放交易體系中得不到實際體現。5用能權和碳排放權有可能一體兼容,但是,碳交易的市場激勵傳遞受到一些體制性因素的約束而失效。因此,中國的碳交易體系構建,需要在頂層設計中考慮碳排放的屬性特點,拓展碳排放交易的市場空間。首先,在認知上將"碳交易"從約束變為一種機遇。其次,國家需要將碳納入預算管理,實現效率配置和有效管控。再次,建立發展導向的碳交易市場,拓展碳市場規模。如納入森林碳匯,碳市場與生態補償相關聯。最后,鼓勵凈零碳城市建設。

Carbon emission entitlements can achieve allocative efficiency through market transactions,which has both theoretical ground and practical support. Carbon emissions,as a kind of bads,need to be continuously compressed or controlled by quota,which is essentially different from any sort of ‘goods ’. Therefore,there are inherent difficulties in the market transactions of carbon emissions. During the construction of domestic carbon market,such a situation will deteriorate. Firstly,it is because that constrained by overlapping factors of economy,politics,environment and society,multiple and complicate checks and balances exist between China and international community, between central and local governments, among local governments and between governments and enterprises,leading to potential uncertainty about the identification and distribution of total emissions. Secondly,the carbon accounting is subject to energy sector and it is not completely independent as a passive commodity. If the choice of an enterprise is connected to its energy efficiency and energy conservation,then the energy use entitlements overlap with carbon emission entitlements. Due to the subordinate and passive attribute of carbon as a commodity,the carbon constraint on the decision making of enterprises may be weakened or marginalized,and thus its price signal to customers would be partly distorted. Thirdly,only an open and competitive market is an efficient one,but judging from the EU Emissions Trading System( EU ETS) and domestic pilot projects,this system is relatively closed. Fourthly,the low quality of carbon-intensive products may impose some constraint on enterprises through selfregulation; but for the carbon locked-in physical infrastructure,its cost can only be borne by the whole society and would fail to be actually reflected in emissions trading system. Fifthly,the energy use entitlements and carbon emissions entitlements may be compatible and integrated with each other; however,the passing-on of incentives in a carbon trading market may cease to have any effect because of some institutional constraints. Therefore,China needs to take into account the attributes and features of carbon emissions in the top-level design and expand the market space for emissions trading during its construction of carbon trading system.First and foremost,China should shift the attitude towards carbon trading from a constraint to an opportunity. Secondly,carbon should be budgeted to achieve allocative efficiency and effective control. Furthermore,the country needs to establish a development-oriented carbon trading market to expand the market size and take measures such as including forests carbon sinks and linking carbon market to ecological compensation. Finally,construction of net zero-carbon cities should be encouraged.