The track running through the quiet, typically English countryside between London and the Sussex coast on first view has little in common with India’s sprawling, busy rail network, but Ivan Stone and his colleagues at Riding Sunbeams hope the former can act as test-bed for technology that could help transform the Indian railways.

Stone is CEO at Riding Sunbeams, a company that unites the worlds of rail technology and clean energy development with a single purpose – to directly provide traction power to sections of the railways from private-wire renewables, initially solar PV but later quite possibly wind too.

Where are there lots and lots of railway tracks, and a lot of sunshine? Answer, India.

After earlier demonstrations of its system, Riding Sunbeams is preparing to take a big step-up next year by connecting a 3.75MW community owned solar array in East Sussex to sections of the London-Eastbourne route, in what is claimed as a rail industry world-first.

The success of Riding Sunbeams’ technology in pilot projects to date, and the leap in scale planned in southern England, has earned the company a place on an Energy Systems Catapult ‘virtual trade mission’ that the British government will run to showcase innovative UK technology to India.

In Riding Sunbeams’ case that means a tilt at a market where railway electrification and renewable power are both close to national obsessions – and for Stone an obvious choice to test the export potential of Riding Sunbeams’ innovations.

Indian opportunity

“Where are there lots and lots of railway tracks, and a lot of sunshine? Answer, India. It really is as fundamental as that. We believe that is an opportunity we just can’t ignore,” Stone tells Recharge.

The potential goes beyond greening the power supply. Riding Sunbeams is an unusual operation – part rail technology start-up, part systems integrator, part renewables developer – that’s co-owned by two charities and has drawn on expertise from the likes of Imperial College and engineering specialist Ricardo along the way.

Riding Sunbeams CEO Ivan Stone. Photo: Riding Sunbeams

“The social as well as the economic model that we pursue has huge potential [in India] as well as the technology,” Stone says, referring to the venture’s founding imperative to give locally-owned developments access to a power-hungry customer – the rail network.

Stone, who has a background working on international infrastructure projects, including in energy, is open about the difficulties in entering a highly complex market, especially to foreign players, with a new technology offering.

“The social and political challenges are enormous, but just partial success would be astonishing,” he says, adding that Riding Sunbeams will use the UK Catapult mission to evaluate the best route, and most appropriate partners, with which to approach the Indian market.

If the prospect of a small-scale operation like Riding Sunbeams (a dozen full-time employees) taking aim at such a massive commercial target seems unlikely, the UK enterprise may have one crucial element on its side – it is apparently the only game in town, globally.

Stone is the first to admit that sounds unlikely. “The idea of putting [renewable] power into the live rail traction system sounds about as easy as could be. Surely, that’s easy? Surely, it’s been done? No, it hasn’t.”

So, Riding Sunbeams is the only one in the world to have so far demonstrated a solution that can directly green-power railways, rather than relying on the grid? “We believe that is genuinely the case at the moment – and that’s a great position to be in.”

Technical devil in the detail

The “technical devil in the detail” is nowhere near as straightforward as it sounds, says Stone, whether in connecting renewables to DC third-rail systems – the solution already demonstrated – or to the AC overhead infrastructure more common on long-distance routes, for which the company hopes to test technology with UK operator Network Rail over the next year.

In simple terms, Riding Sunbeams is trying to marry a variable generation source with an extremely intermittent consumer (a section of the rail track) – one with ferocious peaks of demand when a train screams through. Along with power conversion issues, this makes taking power directly from renewable generation a technical challenge.

“We want to demonstrate direct-wire system works, then we’re into optimising the system,” says Stone.

Later “you can broaden the base of your renewable generation – why not use a bit of wind – or you smooth your supply and demand by using a bit of storage”. This depends on the profile of each section of the rail network.

Crucially, he adds, “our business model is proving we can provide unsubsidised direct wire at or below the market rate for the rail traction network”.

If it can successfully develop a full array of solutions – which Stone says would include some elements of patented technology – Riding Sunbeams would be able to offer a platform for direct power decarbonisation to railways, including underground and metro systems.

In the UK alone, the company's research reckons renewables have the potential to directly power about 10% of the DC rail network.

With such a prize in view, aren’t the giants of the rail technology sector – the Alstoms, ABBs and Siemens of the world – queuing up to discuss a piece of the action?

Stone is cautious in this respect, but says: “It would be untrue to say that we aren’t having very interesting discussions with a variety of organisation, whose names you might predict.”

Societal mission

But Riding Sunbeams does have a very public supporter on the clean generation side of the equation in the form of Thrive Renewables, the developer that along with the Friends Provident Foundation in 2020 became the venture’s first commercial investor.

We’re a for-profit organisation – but we have a very clear vision of how that’s applied and who benefits.

Thrive was founded by Dutch sustainable finance giant Triodos, and is now a separate organisation owned by some 5,000 individual and impact investors. According to Stone both Riding Sunbeams’ investors will keep it firmly focused on its core mission of community and societal benefit – an aspect of its work that he hails with the same level of enthusiasm as its technical achievements of linking green power with live rails.

Stone’s ambition for Riding Sunbeams is to make it as big as possible while staying true to its founding principles.

“We don’t see a fundamental conflict,” he says. “We’re a for-profit organisation – but we have a very clear vision of how that’s applied and who benefits.”

Note: Update amends for correct ownership status of Thrive Renewables