Calendar An icon of a desk calendar. Cancel An icon of a circle with a diagonal line across. Caret An icon of a block arrow pointing to the right. Email An icon of a paper envelope. Facebook An icon of the Facebook "f" mark. Google An icon of the Google "G" mark. Linked In An icon of the Linked In "in" mark. Logout An icon representing logout. Profile An icon that resembles human head and shoulders. Telephone An icon of a traditional telephone receiver. Tick An icon of a tick mark. Is Public An icon of a human eye and eyelashes. Is Not Public An icon of a human eye and eyelashes with a diagonal line through it. Pause Icon A two-lined pause icon for stopping interactions. Quote Mark A opening quote mark. Quote Mark A closing quote mark. Arrow An icon of an arrow. Folder An icon of a paper folder. Breaking An icon of an exclamation mark on a circular background. Camera An icon of a digital camera. Caret An icon of a caret arrow. Clock An icon of a clock face. Close An icon of the an X shape. Close Icon An icon used to represent where to interact to collapse or dismiss a component Comment An icon of a speech bubble. Comments An icon of a speech bubble, denoting user comments. Ellipsis An icon of 3 horizontal dots. Envelope An icon of a paper envelope. Facebook An icon of a facebook f logo. Camera An icon of a digital camera. Home An icon of a house. Instagram An icon of the Instagram logo. LinkedIn An icon of the LinkedIn logo. Magnifying Glass An icon of a magnifying glass. Search Icon A magnifying glass icon that is used to represent the function of searching. Menu An icon of 3 horizontal lines. Hamburger Menu Icon An icon used to represent a collapsed menu. Next An icon of an arrow pointing to the right. Notice An explanation mark centred inside a circle. Previous An icon of an arrow pointing to the left. Rating An icon of a star. Tag An icon of a tag. Twitter An icon of the Twitter logo. Video Camera An icon of a video camera shape. Speech Bubble Icon A icon displaying a speech bubble WhatsApp An icon of the WhatsApp logo. Information An icon of an information logo. Plus A mathematical 'plus' symbol. Duration An icon indicating Time. Success Tick An icon of a green tick. Success Tick Timeout An icon of a greyed out success tick. Loading Spinner An icon of a loading spinner.

Playing at the energy innovation casino table

© Shutterstock / BLGKVRFC Power
RFC Power hopes for a winning hand with its dual-membrane battery

Once in a while something comes along which suggests that all is not yet lost in terms of the idea that the UK is actually capable of securing real skin in the low carbon energy technologies game.

Imperial College has established a spin-out company known as RFC Power to commercialise work being done on the development of a genuinely low-cost, long-term energy storage solution based on the redox (reduction-oxidation) battery.

At this great British learning and research institution, a group of engineers and chemists have come up with a polysulphide-air redox flow battery (PSA RFB) which could become a gamechanger in the large-scale energy storage sphere.

According to those working on the project, its dual-membrane design overcomes the main problems with this type of large-scale battery, apparently at last opening up its potential to store excess energy from, for example, renewable sources such as large wind and solar farms.

This development is probably pivotal and could enable the UK to gain real traction in the still nascent super-large batteries opportunity, assuming RFC Power doesn’t get gobbled up by foreign interests in the face of British industrial and investment apathy.

According to Imperial, though redox flow batteries are strong candidates for grid-scale energy storage due to their potential to decouple power and energy capacity, the technology has achieved limited market penetration due to issues related to “cross-contamination, sluggish redox kinetics, low energy and power densities, and relatively high cost”.

A redox flow battery  converts chemical energy into electrical energy through reversible oxidation of so-called working fluids, otherwise called electrolytes. The idea first saw the light of day in the 1970s.

The amount of energy stored is governed by the volume of the electrolyte, making the design potentially easy to scale up.

However, the electrolyte used in conventional redox flow batteries – primarily vanadium – is expensive and mainly sourced from either China or Russia.

Given currently fractured global politics because of Russian president Putin’s war on Ukraine and growing distrust about China’s economic colonisation intentions and increasingly global military capabilities, there is a serious need to find alternatives; preferably cheaper too.

The redox project was kicked off well before the invasion and, for that matter, the UK’s hugely self-destructive exit from the EU (Brexit). Moreover, it attracted a sizeable European Research Council (ERC) grant in Q3 2019.

That’s roughly two years after Imperial set up RFC Power and a year before the start-up made it to the 2020 finals of a European future energy competition – New Energy Challenge.

This is a start-up competition jointly organised by Shell, Rockstart, YES!Delft and Get in the Ring, designed for entrepreneurs in Europe and Israel developing disruptive solutions that could be vital in accelerating the energy transition.

The mission of the Imperial team, led by Professors Nigel Brandon and Anthony Kucernak, has been to find widely available alternatives, to vanadium especially.

Their approach uses a liquid as one electrolyte and a gas as the other – in this case polysulphide (sulphur dissolved in an alkaline solution) and air.

RFC power © Supplied by Imperial College Lon
The dual-membrane polysulfide-air redox flow battery (PSA RFB).

However, the performance of polysulphide-air batteries to date has been limited because no membrane could fully enable the chemical reactions to take place while still preventing polysulphide crossing over into the other part of the cell.

So the Imperial team decided to try using two membranes to separate the polysulphide and the air, with a solution of sodium hydroxide between them.

According to Prof Brandon, who happens to be Imperial’s dean of the Faculty of Engineering: “To make this cost effective for large-scale storage, a relatively modest improvement in performance would be required, which could be achieved by changes to the catalyst to increase its activity or by further improvements in the membranes used.”

Which is where RFC Power is poised to come in. OK, so it didn’t win the competition, but the company’s name has been circulating within influential circles.

Even before the contest, in January 2020 it secured seed investment from venture capital provider IP Group in return for a 33.2% stake.

Sadly, IP is American and not local British.

In November 2021 it emerged that RFC Power signed up to a strategic collaboration with Ceres Power to gain access to its engineering and commercial expertise in exchange for 8.5% of itself.

Now regarded as the UK’s most valuable cleantech company, Ceres was founded 20 years ago and is also heritage Imperial.

In February this year, PwC named RFC Power as One to Watch in the Energy Sector as part of its UK Net Zero Future 50 listing.

And, last month (MAY 2022), it entered into a collaboration with Shell via the energy super-major’s GameChanger programme. This isn’t just about money as RFC Power will be introduced to experts from across Shell to help with de-risking critical aspects of its redox technology.

Now, whether RFC Power will make it to the top of the heap with an idea that started life at Imperial, with initial funding through the UK Research and Innovation Engineering and Physical Sciences Research Council, while also remaining a genuine British success story, is anybody’s guess…

Recommended for you

More from Energy Voice

Latest Posts