Renewables obligation: certificates and generation - December 2026

This is a pre-announcement, not a data release. There are no numbers to brief on.

DESNZ has confirmed it will publish December 2026 ROC issuance and generation data on 8 April 2027 at 09:30. The publication itself is eleven months away. The announcement contains no figures, no tables, no trends.

A memo structured around "what the numbers show" would be fabricating content. I'll write what's actually useful: a short note on what the RO data release covers and why it matters when it arrives.

---

What this is

A scheduled release notice. DESNZ publishes monthly Renewables Obligation certificate and generation statistics on a rolling basis, roughly 15 months after the generation month. December 2026 data will land on 8 April 2027. This announcement confirms the date; it contains no data.

What the release will contain (when it arrives)

Monthly RO data covers:

- ROC issuance volumes by technology and country (England & Wales, Scotland) - Accredited generation in MWh under the RO scheme - Technology mix of generating stations still drawing ROCs

The RO closed to new applicants on 31 March 2017, but accredited stations continue earning ROCs for their full 20-year support period. The last RO stations will exit around 2037. Until then, the scheme remains a material line item on supplier costs, passed through to consumers via the obligation level and buyout price.

Why this matters when the data arrives

Three things to look for in December 2026 data:

1. Declining issuance trajectory. Early RO stations (pre-2010 onshore wind, landfill gas, small hydro) are reaching end of accreditation. Total ROC issuance should be falling year-on-year. The rate of decline tells you how quickly the RO cost burden is unwinding.

2. Technology composition shift. As older, smaller stations drop off, the remaining RO fleet skews toward large offshore wind projects accredited between 2014 and 2017. These are the highest-output, highest-ROC-value stations. Average ROCs per MWh may hold steady even as station count falls.

3. Buyout price and mutualisation exposure. The RO buyout price rises with RPI annually. If issuance falls faster than the obligation level adjusts, the recycle value per ROC increases, but supplier shortfall risk also shifts. Any supplier unable to meet its obligation pays the buyout, which is redistributed. The monthly data is the leading indicator for the annual obligation calculation.

Context

The RO is a legacy scheme running on autopilot. It attracts less attention than CfDs or the Capacity Market because nothing is changing by design. But it still costs consumers roughly £6 billion per year through supplier obligations, and the unwind matters:

- For suppliers: the obligation level set each year determines their ROC purchase requirement. Falling issuance should mean a falling obligation, but the lag is deliberate and the adjustment imperfect. - For RO generators: revenue certainty continues until accreditation expires. No cliff edge, but no extension either. Post-RO, these stations face merchant markets or repower under a different support mechanism. - For the system: RO wind and biomass output is not dispatchable and not responsive to price signals. The scheme pays per MWh regardless of when the power is generated. This is the "old CfD problem" before CfDs existed.

What not to do with this announcement

Do not treat a release date confirmation as a data event. There is nothing to model, nothing to trade on, nothing to brief a board about. File it, set a calendar reminder for 8 April 2027, and move on.