The UK government has set an explicit target to achieve a net zero electricity system by 2035. But what does this mean, and what might that look like on a day-to-day basis? In particular, how might this net zero electricity system operate during the more challenging periods of the year?

Project duration: December 2021 – ongoing


Regen is working alongside National Grid ESO’s Bridging the Gap programme to addresses the challenge of how a net zero power system could operate during more challenging periods of the year. How will a very low carbon electricity system, with a very high proportion of variable renewable energy, significant new demand from EVs and heat pumps, and much greater levels of flexibility, remain flexible enough to deal with the diverse conditions that the British weather and energy system will throw at it?

In early 2022 we completed the first ‘Day in the Life’ showing how a 2035 net zero electricity system may operate on a challenging day in winter, a day with high demand and low availability of renewables. Our report looks at how we can continue to operate a secure system and manage low renewables through energy storage, flexible low carbon generation and interconnection.

We are now working on a second ‘Day in the Life’ focusing on a day of challenging summer conditions. This means finding ways of keeping the system secure and stable when demand is low and the availability of wind and solar is high. Traditionally much of the system’s stability services and its ability to respond to unexpected faults has been provided by fossil fuel generation – by 2032 we need those services, as well as our energy, to come from zero carbon sources.

The work looks at some of the specific pieces of the puzzle needed to achieve a net zero electricity system by 2035. How much offshore wind will be located in the various seas around the UK coast? What technologies and fuels are providing low carbon flexibility and dispatchable generation? What is the role of overseas interconnection? What role do domestic and non-domestic consumers play in an increasingly digitalised and data-driven energy system?

Day in the Life 2035 – a winter’s day

Click below to view the full publication:

Download a version to view offline here

This publication was launched in March alongside National Grid ESO’s Bridging the Gap programme. Read the press release here.

With particularly high levels of interest in the project, we hosted a Q+A session to discuss some of the assumptions and uncertainties in the Day in the Life 2035. A recording of the session can be found here.

Day in the Life 2035 – a summer’s day

This analysis will be published soon. To stay up to date with the launch of Regen’s publications and other market insight, sign up to our mailing list here. 


If you are interested in finding out more about this project or our future energy systems work, please contact Jonty Haynes.


People on this project

Johnny Gowdy
Johnny is a director of Regen and leads the development of our advisory projects,…
Jonty Haynes
Senior energy analyst
Jonty is a senior energy analyst at Regen delivering a range of technical support…
Prina Sumaria
Local energy coordinator
Prina specialises in local energy issues, supporting Regen's community energy programme. During her time at…

Stay informed

Sign up to the Regen newsletter to receive a monthly digest of our work to revolutionise the UK energy system, and industry insights.

We take care of your personal data. We will only contact you according to your preferences and will NEVER share or sell your details. See our privacy policy for more information
  • This field is for validation purposes and should be left unchanged.