Government advisers have called for the creation of a new distributed energy register to help inform the operation of the capacity market.
The Panel of Technical Experts (PTE) said the register should include information on the status of connections to electricity distribution networks and the commissioning dates for new assets. The government, Ofgem and National Grid should consider how best to extract this information from distribution network operators (DNOs).
In the latest of its annual reports on the capacity market, the panel said it has already urged the electricity system operator (ESO) at National Grid to compile more robust data on distributed generation.
Since receiving the recommendations in 2017 and 2018, the ESO has gained access to information on the power output of distributed generators via Electralink – the operator of the Data Transfer Service.
However, the PTE said it remains “concerned and disappointed” about the “lack of progress in this area”. It said Electralink lacks the corresponding capacity figures the ESO needs to accurately forecast the availability of distributed generation.
The panel highlighted the risks of non-delivery due to a range of issues, including the ongoing suspension of the capacity market, Ofgem’s proposed overhaul of network charges and introduce of new emissions limits, particularly given that distributed energy resources account for the majority of capacity procured in the auctions to date.
One possible solution would be to require DNOs to report booked and live connections on their networks to the ESO. At a minimum, the panel said DNOs should be obliged to compile a register of distributed generation “as a matter of urgency”.
The panel said it is “unclear” what are the barriers to the collation of this data as the ESO has operated the Transmission Entry Capacity register for many years.
A register covering distributed energy resources has already been proposed by the Energy Data Taskforce and by the Energy Networks Association as part of its Open Networks project. But the PTE said it may be quicker to bring about its creation through a modification to the Distributed Connection and Use of System Agreement.
On a separate note, the panel said the ESO should reconsider how it incorporates so-called “black swan” events – those which are highly unlikely but have severe consequences – into its forecasting.
It drew attention to Britain’s ageing fleet of gas-cooled nuclear reactors, noting that both the Hunterston B and Dungeness B power stations have experienced extended outages over the past year.
In the case of the former, the shutdown was prompted by the discovery of cracks in the graphite cores of the plant’s reactors. The panel said this problem is likely to dictate how much longer the reactors can be operated safely and expressed concerns over the potential for this to emerge as common issue across the whole fleet.
The PTE is responsible for scrutinising the operation of the capacity market and contracts for difference scheme for the government. Its report was published alongside the procurement targets for capacity market auctions due to take place in 2020.