The revenues raised from the Emissions Trading Scheme flow to Westminster too but we do not yet have transparency over how these revenues are used to support decarbonisation in Wales.
Mae'r refeniw a godir o'r Cynllun Masnachu Allyriadau yn llifo i San Steffan hefyd ond nid oes gennym dryloywder eto o ran sut y defnyddir y refeniw hwn i gefnogi datgarboneiddio yng Nghymru.