2023-05-05-IEA-构建中国统一的全国电力市场体系_77页_5mb

For decades, neighbouring systems have entered into trading agreements to share resources and reserves. As countries transition, the benefits become even more apparent as systems with high shares of wind and solar PV benefit further from the smoothing effect of larger areas. International experience shows that market integration can lead to efficiency gains, reduced CO₂ emissions, and better renewable integration, but the choice of model depends on local conditions. China's case involves balancing national co-ordination with provincial autonomy, and the challenge of integrating existing administrative mechanisms with market-based systems.

Among several models, a national surplus market allows local markets to remain autonomous while improving resource sharing on a wider scale. This model, similar to secondary market arrangements in Europe and Central America, enables bi-directional trading only when there is surplus, preserving local designs and operations. It builds on China's existing interprovincial spot market and involves coordinated clearing of national and local markets, updating transmission capacity allocation, and ensuring transparent wheeling charges.

Regional co-ordination, even at a moderate level, delivers significant benefits. For instance, a north-south surplus market model, optimizing within predefined northern and southern grids before allowing interregional trade, shows substantial improvements in cost-efficiency and carbon reduction. Advanced volume coupling models like CETO, where a national market optimizes flows between regions, offer higher efficiency but may involve greater harmonization challenges.

Economic dispatch and administrative allocation reductions are critical enablers. Even without full interregional trade, transitioning from historical full load hour allocations to partial or full economic dispatch in selected provinces can reduce operating costs by up to 18% and renewables curtailment significantly. A similar impact can be observed when combined with surplus markets and strong dispatch reforms.

Priority dispatch for renewables also provides immediate benefits, reducing operating costs and emissions while minimizing curtailment without full market integration. Furthermore, integrating market-based reforms with administrative planning helps guide investments and ensure power system resilience while avoiding costly overbuilds.

Institutional design is key. Strong national coordination mechanisms, market operators, and regulators are necessary to oversee and facilitate market integration. These institutions should complement provincial autonomy, ensuring consistency in national outcomes while respecting regional specificity. Market rules must be transparent, and regulatory bodies like those in the European Union can guide monitoring and dispute resolution.

Regarding transmission infrastructure, tariff reforms addressing "tariff pancaking" can improve interprovincial trade efficiency. Shifting from energy-based pricing to congestion-based mechanisms, as seen in the European Union, allows for fairer cost allocation and higher usage of interconnectors.

Flexibility mechanisms, such as capacity remuneration mechanisms (CRMs) or capacity markets, must be carefully designed to support legacy thermal plants while incentivizing renewables and distributed resources. Such mechanisms should not distort markets or disincentivize participation in spot and ancillary services markets.

Lastly, planning should increasingly adopt market-aligned logic, where projections reflect dispatch outcomes and existing market designs. This involves probabilistic assessments and coordinated system planning, rejecting rigid administrative controls to capture evolving needs, especially climate and VRE integration goals.