Designing Viet Nam’s carbon market for the energy sector: interactions among the carbon price, free allocation, and net ets value pass-through into electricity prices

Tóm tắt

The design of an emissions trading system (ETS) for the energy sector depends jointly on the carbon price, the free allocation rate, and the extent to which the electricity sector’s net ETS value is reflected through the electricity-price channel. This study extends the static PEP-1-1 computable general equilibrium (CGE) model, calibrated to a 37-account Social Accounting Matrix (SAM) constructed for Viet Nam for 2019, by incorporating sectoral emissions accounting, free allocation, and an ETS accounting balance for a regulated electricity sector. A grid of 126 scenarios combines seven carbon prices (50,000-2,500,000 VND/tCO₂), three free-allocation rates (100%, 90%, and 80%), and six pass-through coefficients (0.1-1.0), with each scenario solved independently around the 2019 base equilibrium. Across the grid, real GDP falls by 0.0048%-5.3104%, the consumer price index (CPI) rises by 0.0058%-6.4877%, household consumption falls by 0.0077%-8.6294%, aggregate output falls by 0.4154%-10.6984%, and modelled emissions fall by 0.6793%-16.9257% relative to the baseline. The sensitivity results indicate a diminishing incremental emission response as the carbon price rises. In the specified local slices, reducing α from 100% to 80% produces larger changes in aggregate outcomes than varying θ from 0.1 to 1.0; because the parameters have different units and ranges, this comparison is not an absolute ranking of parameter importance. FIN_GAP_ELEC, which represents the share of the electricity sector’s net ETS value not reflected through the price channel, is zero when pass-through is complete (θ = 1) and ranges from -VND 48,447 billion to +VND 4,552 billion on the model’s accounting scale. It is not an observed corporate cash flow or government fiscal flow. The analysis is confined to the comparative-static grid; the three-period quasi-dynamic extension is excluded because it lacks a period-specific non-ETS baseline. The study does not identify an optimal policy configuration or make legal recommendations; the findings are conditional on the model’s data, structure, closure, and assumptions.