Almost everyone who agreed to be interviewed for this article stressed that Jonathan Brearley had been “dealt a very difficult hand”. Some saw this as a mark of achievement, some as an excuse for failure. Often it was a mixture.

Certainly if your second week in the job starts with a global pandemic – and that isn’t even the biggest problem faced in your tenure - you can’t be accused of having an easy ride.

This was February 2020, with Brearley stepping up after two years as director for systems and networks to replace Dermot Nolan. At the time I remember industry sources telling me they were not exactly bowled over but neither were they disappointed. Brearley was seen as very capable, politically savvy and knowledgeable about the sector – but also as an archetypical civil servant.

One former colleague says: “He was a safe pair of hands and well liked by people in the organisation. But there wasn’t really a sense of what his vision for Ofgem was and how he was going to do things differently.”

Another ex regulator says: “He had a very different style to Dermot, who was very cerebral in private and combative in public. Jonathan is much more down to earth and certainly much more diplomatic.”

An early focus – and one he has continued to press – was diversity and inclusion. “He talked a lot about his mixed race family and his desire to promote diversity in energy. It never came across as a corporate box-ticking thing. He really cares about it.”

However, this has not necessarily played out in one of the key features of his time at the helm of Ofgem - a near constant restructure. “A lot of good people ended up leaving the business, including a number of senior women”, says one insider.

“He was badly advised at great cost and it’s been really disruptive” says another source. “People were forced to re-apply for their jobs and in many cases told they weren’t up to it. Then you had directors with ‘interim’ at the front of their job titles for years in some cases.”

A senior figure at an energy suppler points out that while there was a degree of consistency in networks, there was a particular churn in retail. “We would just have got one person up to speed on all the issues we were facing and then they’d be moved on – or out – and there was someone else to bring up to speed.”

Headcount has ballooned at Ofgem during Brearley’s reign, from 910 in 2020 to 2,231 today.

One source observes that “Jonathan has been very good at pulling the right levers to release more money into Ofgem but you have to question whether it’s offering value for money to grow staff numbers that much.”

While former colleagues describe Brearley as approachable within the business, industry sources say he has not always been as visible in the field. According to an energy retail source “we would often raise an issue about a particular team at the highest level only to find ourselves circling back to that same team with little evidence of any steer from above”.

Many sources say the arrival of Mark McAllister as chair in 2023 has given Brearley the support he often lacked under predecessor Martin Cave.

One source says “Martin was from an academic background and with the challenges of the past few years, you really needed someone who has been in the trenches.”

All interviewees agreed that one of Brearley’s greatest strengths as Ofgem chief executive has been his political nous. “There’s a respect between Ofgem and the Department for Energy Security and Net Zero that has not always been there.”

However, others question whether this closeness to government will allow Brearley to tell uncomfortable truths to ministers. In particular, will Ed Miliband’s pledge to cut domestic energy bills by £1,400 by 2030 put pressure on network price controls, will Brearley lobby for a social tariff and can he argue for some of the costs of the energy transition to be put into general taxation?

Much of these difficult conversations in Brearley’s first term centred around energy retail – and there is consensus among our interviewees that this trend will continue.

Nolan apparently told his successor he would be the first Ofgem chief executive whose time would not be dogged by problems in retail. This couldn’t really have been wider of the mark. In the space of less than a year during the height of the energy crisis, 29 suppliers exited the market, while the government was forced to step in to subsidise household energy bills as wholesale power prices rocketed.

Opinions are mixed on how well Brearley handled the fallout and to what extent he should have seen it coming. Interviewees agree he was saddled with a market already flooded with unsustainable businesses. However, while some feel he did little to heave shut that particular barn door, others point to the demands the Covid response put on his time as mitigation for a lack of proactivity.

While the market may have calmed, it remains in dire need of reform, our interviewees agreed. One senior retail figure says: “It is really, really hard to operate in energy retail and there is very little recognition of that from Ofgem. In that sense very little has changed from Nolan’s time. We are still an easy target and in the next five years I would like to see Jonathan take a more considered approach to the sector.”

Another says: “You are not going to get to 2030, let alone 2050, without retailers because we are the gateway to decarbonisation. I’d like to hear Ofgem saying that more.”

Some sources questioned if Brearley really has a vision for energy retail, including what life after the price cap might look like.

But according to one supplier “he doesn’t need a vision, he just needs to be clear about what the interplay between suppliers and customers looks like and how we can be empowered to help them benefit from decarbonisation”.

The checklist on retail for the next five years from our interviewees is exhaustive - and potentially exhausting: complete the smart meter rollout; deliver market-wide half-hourly settlement; reform or replace the price cap (preferably with targeted support for the most vulnerable); drive forward adoption of low-carbon tech and make flexibility mainstream; tackle the debt pile and stimulate tariff innovation.

That’s without touching on the particular challenges in business retail where, according to one source, “not only is there no vision, there’s barely any acknowledgment”.

On the face of it, networks have been the most stable area of Brearley’s stewardship, not withstanding the clean sweep of appeals to its RIIO2 final determinations for gas and electricity transmission networks.

“He is much more comfortable with networks than he is with retail” says one senior figure in the sector, although caveating that with long-serving associates such as Akshay Kaul (currently director general, infrastructure) he has had strong and stable support.

Another network director says: “He deserves a lot of credit for how he has evolved network regulation. Distribution System Operator (DSO) functions and the Accelerated Strategic Transmission Investment (ASTI) framework are big steps forward. And generally he has struck the right tone between investment ahead of need and sweating the assets or looking at the demand side.”

However, the next five years will test Brearley’s appetite for evolution, with energy networks proposing a significant gear shift in investment.

One senior figure in transmission says the business plans for RIIO-T3 are “deliverable but only if Ofgem turns all the lights to green”. Sources say Brearley will also have ever tougher calls to make on the balance of risk and return for investors.

Distribution sources say Ofgem’s vision for ED3 remains clouded, although they welcome the acknowledgement that deferring investment in the network in favour of a flexibility first approach could lead to a “false economy”.

When it comes to the gas networks, the 2026 deadline for a government decision on the future role of hydrogen remains the elephant in the room. One gas source says: “Jonathan is very happy to defer this one as a government decision, which is fair enough. But there is a whole conversation about exactly what full electrification of heating would look like that really needs to happen before that decision in 2026. And Ofgem is doing nothing to further that discussion.”

While networks may be a comfort zone for Brearley his heart really lies in the architecture around the energy system, sources say. Having been instrumental in the establishment of Contracts for Difference and the Capacity Market, this is perhaps no surprise. And nor is his support for the creation of what became known as NESO.

“I would question whether NESO would even be operational by now if it wasn’t for Jonathan keeping everyone’s feet to the fire”, says one source.

But now the NESO is a reality, at both an arms length from government and acting as advisor to it, Brearley will have to work out where Ofgem sits in relation to it.

“Regulating the system operator has always been difficult but now it’s the NESO that has gone up a few notches”, says one source. “It’s been seen as the answer to so many problems and it needs Ofgem’s support to fulfill its potential. But at the same time Ofgem has to be absolutely cracking down on any slippage on timeframes.”

Another source puts the expectation succinctly as “you need to help them or beat them up”.

An electricity transmission source says: “The connections reforms are a real hold-your-breath moment. If they don’t do the job, we can’t do ours. And then you have a lot of explaining to do. Jonathan Brearley’s legacy really depends on NESO getting this right.”

The fear is that the process will be held up by appeals from disgruntled generators kicked out of the queue.

Speaking at Utility Week Forum last November, McAllister suggested legislation might be needed to ward off such approaches. Many sources call for Brearley to be more vocal in pushing for this kind of protection from government.

There are also exhortations for a clearer plan on domestic flexibility. The Clean Power 2030 action plan points to the need for up to 12GW of capacity but with little detail on how this will be achieved. As with connections reform, it will be NESO in the driving seat for this this, but our interviewees were clear that Ofgem will have to be closely involved.

One source says: “It’s not encouraging that one of the first things NESO has delivered is to completely mess up the demand flexibility service. And Ofgem just let them do it. That’s very worrying because the regulator should have made them take a second look and consider the wider impacts.”