The role for energy storage as an alternative to Hinkley Point C

The UK Prime Minister’s decision to review the deal for a new 3.2GW nuclear power station, Hinkley Point C, in Somerset, to work alongside the existing Point B plant, has seen the industry call for a review of alternative power sources to meet the country’s future power demands, and help it transition to a low-carbon energy system.

The technological and logistical challenges parallel projects have encountered have drawn most criticism, with a political narrative also unfolding as a subplot. But the sheer cost of the project is considered by many to be the most alarming factor, with a starting price of £92.50 per MWh for 35 years escalating with inflation.

“For that price tag, you could transition the UK to a low carbon energy system using renewables and storage. It is a ridiculous amount of money,” says Philip Hiersemenzel, a spokesperson for storage firm Younicos. “If renewables got anything like that [funding], everyone would be screaming ‘socialism’. It’s not even up for discussion.”

The march of technology has rendered the wisdom of the new Hinkley blueprint obsolete, Hiersemenzel suggests. “Previous decisions [about Hinklet Point C] would not be made today”. With the rate of development of storage technology, renewables present a viable alternative, even to such large-scale projects as Hinkley Point C, he suggests.

“Storage is easy to deploy, in under a year, and it is only getting cheaper, in the same way as wind and solar have. If we take history as a guide, nuclear always proves more expensive. Common sense says renewables are cheaper, and they don’t have the same issues around waste and risk.”

He adds: “Renewables, with storage, are perfectly capable of providing all the power the UK needs. The best case for the new reactor at Hinkley Point is that it would be online in 10 years – so you don’t even have to look at renewables and storage now.”

At the same time, Hiersemenzel does not advocate a straight swap-out. “Even at my most optimistic, this transition will take 10-15 years.”

The expansion of the site at Hinkley has stimulated a huge debate on the UK's nuclear energy future. Source: Flickr.CND.
Nuclear base load

But commentators suggest 3.2GW of power generation, meeting 7% of UK energy demand as the new Hinkley site sets out, is not so easily replicated by other means. “The specification levels are pretty remarkable,” says Tim Grejtak, energy expert at Lux Research. “Seven per cent can be the difference between lights staying on during peaks hours, and them going off.”

He adds: “It’s a substantial proportion of the energy mix to make up, and it just kind of speaks of the problems of scale the energy industry faces. There are ways around these capacity problems, but they are certainly not easy, and the scale tells you that.

“Renewables will of course go on to be the cornerstone of our future energy needs, without question. And some of these renewable assets are scaling quickly. But the question is whether it is the right type power.”

He raises the issue of the constant base load, provided by nuclear and fossil fuels, and the corresponding intermittency of such sources as solar and wind. For Grejtak, it is not as much as question of technology, as how to integrate new energy sources onto a legacy system. “Sometimes that system’s 50, 60, or 70 years old; it’s important for grid operators to maintain the reliability of the overall system.”

Western Power Distribution, responsible for providing a connection offer for any demand or generation customer in its region, and agnostic to the type of generation, warns only fossil fuels, and perhaps tidal generation, could match the base load generation of a nuclear reactor.

“We are still a very long way from having enough renewable generation with associated storage to displace large scale projects,” says Steven Gough, innovation and low carbon networks engineer at Western Power Distribution.

“The UK will continue to need a breadth of technology to ensure it can continue to balance the system. Storage solutions will help, as it will allow some of the uncontrollable renewable generation to be shifted to times of high demand over the course of a few hours.”

Gough adds: “There is not any currently commercially viable solutions to inter-seasonal storage to move the excess of generation in the summer months to the peak demand in the winter months.”

For his part, Hiersemenzel says the “must-run capacity” of the base load takes up space, and complicates the transition to renewables. “There is a limited amount of renewables you can load before they become a nuisance technically and economically,” he says.

Indeed, nuclear and fossil fuels dictate the energy system is organised according to old rules, he suggests. “No one needs base load generation. That was made up 100 years ago,” he says, pointing to grid stabilisation services afforded by latest battery storage technologies.

Notably, he cites those storage technologies wrapped into UK Power Networks’ Big Battery initiative in Leighton Buzzard and the National Grid’s imminent roll-out of enhanced frequency response (EFR) mechanisms, which Younicos has been variously engaged in.

Former energy secretary Amber Rudd at the Big Battery project.
Efficiency and stabilistion

Indeed, doubts over the design, funding and long-term value of Hinkley Point C, persist, and continue to grow.

“Strategically, it is not the way to go to solve the UK’s energy needs. Rather than building more generational capability, the UK needs to invest in the efficiencies that can be derived from energy storage,” says Scott Schotter, chief marketing officer at energy service provider Alevo.

Schotter points to the fact the UK’s National Infrastructure Commission said in March that smart power, hinged on energy storage, as well interconnection and demand flexibility, could deliver reductions in demand equivalent to the generating capacity of four Hinkley-sized nuclear plants, and save the nation £8 billion a year by 2030.

“The Government should focus on these smart energy initiatives and bring in the regulatory and legal frameworks that will assist their deployment while insisting that the regulator encourages their use,” says Schotter.

Grejtak at Lux also points to the importance of efficiency gains from smart technologies. “Efficiency has always been the less traditionally sexy part of the conversation, but there can be some strong and inexpensive efforts made on that front,” he says.

The National Grid is about to announce the results of its open tender for 200MW of EFR, to be in place in 2017. The EFR mechanism, which relies on new battery storage technologies, will ensure more rapid stability of the grid as the balance between generation and load becomes increasingly complex.

EFR has been the primary catalyst for storage in the UK to address system imbalances and inertia from renewables, as well as the closure of deep-coal mining in the UK.

William Tokash, senior analyst at Navigant Research, says: “The longer term focus for storage isn’t about nuclear capacity replacement, which you can do with natural gas, wind and solar. Energy storage will be driven by better economics for specific required energy storage applications.

“The EFR tender is driven in part by renewables intermittency increasing the need for that type of fast-responding regulation. There’s not much consensus on the exact amount of new regulation that will be required as more renewables are added over time. National Grid has cited the growth of intermittent wind generating assets as a driver of this first procurement.”

Challenges and solutions

But Gough at Western Power Distribution warns: “There is a lot of interest in energy storage as many of the renewable generators are focusing on storage as renewable generation subsidies have dropped off. The cost of batteries has dropped significantly and will continue to do so – although, not by as much as solar panels, as the raw material costs are still, and will continue to be, quite high.

“However the commercial model is still not well understood making it hard to tell if these projects are commercially viable. Many existing renewable projects are unlikely to install storage as their projects are already giving a rate of return. The economics of both wind and solar have been affected from planning changes and a drop in subsidies, making them more difficult to progress.

“The additional upfront capital cost of a storage solution will only make this more difficult. Storage alongside renewables will help but it will not be enough to offset larger scale projects unless there is a substantial uptake, which could cause a variety of other problems such a distribution constraints, inertia reduction, transmission voltage control and transient stability.”

Gough says a possible short-term fix to inter-seasonal demand could be more fossil fuel generation – either gas, clean coal, or disaggregated diesel generation. “But all have carbon footprints,” he observes.

Down the line, he suggests hydrogen, or perhaps compressed air storage, could be options for this inter-seasonal balancing act in the future, with either gas, diesel or coal generation poised as back-up for any shortfall.