A robust and resilient low-carbon energy system by 2035 is possible, but there are still key areas that need additional investment and expansion.

This is according to a new report – A Day in the Life of 2035 – produced for National Grid ESO by Regen, which looked at system challenges like keeping it balanced, ensuring operability, managing constraints and security of supply, within a system where renewable energy supplied 75-80% of demand.

The independent energy analysts modelled two days in 2035; one in winter that assumed high demand and low renewable generation, and one in summer that assumed low demand and high renewable generation.

Ultimately it found that the operator would be able to balance the system on both days, although flexibility will be key.

The technologies and systems needed to manage the grid are either already available or in development, but investment will be needed to expand network infrastructure, energy storage capacity, dispatchable low-carbon generation, interconnectors and demand side flexibility.

“With energy security firmly on the minds of UK policymakers, a key question is how a decarbonised electricity system based on a high proportion of renewable generation can be operated securely,” said Johnny Gowdy, director at Regen.

“The ‘Day in the Life of 2035’ study takes on that challenge to show that not only is a robust and resilient decarbonised electricity system possible, but it could bring a range of benefits, including protecting consumers from high gas prices and establishing the UK as a world leader in the delivery of low carbon energy.

“Many of the key innovations and technologies that we need to operate such a system are already underway, but getting them to scale in the timeframe required means a step-change in investment.”

Regen found that far greater participation and engagement by both domestic and business consumers will be needed, so they can provide demand side flexibility, which will be enabled by smart technologies and market mechanisms.

Britain is already starting to lean on demand side flexibility to balance the energy system, with the ESO expected to launch its Demand Flexibility Service in the next few months. This is expected to help meet demand over the tight periods in the coming winter, forming one of the enhanced measures set out by the operator in its Winter Outlook Report recently.

Demand Flexibility Services could potentially add around 2GW+ of capacity, according to the operator, although some have cautioned that the incentive is too low to drive large scale adoption.

Suppliers have also begun to launch demand flexibility schemes to help manage tight system conditions, including OVO’s “Power Move” and Octopus Energy’s “Saving Sessions”.

Beyond demand flexibility, short- and long-duration energy storage will need to increase to keep 2035’s energy system balanced.

While the battery energy storage market has seemingly gone from strength to strength in Britain, the long-duration market has lagged. This is predominantly due to the high upfront cost of technologies like pumped hydro, with many in the sector calling for the introduction of a support scheme.

Electrolysis plants and interconnectors with neighbouring markets will also offer system flexibility, allowing the import and export of energy during times of low and high renewable output.

Regen also highlighted a need for increased diversity of renewable energy technologies and their locations, such as floating wind farms in the west of the UK. An increase in the capacity of low carbon dispatchable generation to replace fossil fuels, such as hydrogen and carbon capture and storage will also be needed.

The final key element needed to ensure National Grid ESO can operate a decarbonised system securely is further investment in network infrastructure, as well as operability solutions, digitalisation and smarter technologies to compliment this.

“This study brings to life the potential challenges of operating a fully decarbonised electricity system and illustrates clearly how they can be overcome,” Rebecca Hart, strategic engagement manager at National Grid ESO said.

“The key message is that it is possible but that we need a whole system approach to making this a reality, with a range of new flexible demand and supply coming from all levels, from domestic consumers right up to hydrogen electrolysis plant.”

A Day in the Life of 2035 builds on previous analysis from Regen and National Grid ESO released in March on the operation of a low-carbon grid.

Additionally, in August Regen released an insight paper identifying seven potential solutions to reduce the cost of balancing and managing constraints.