Ashish Sharma joins CPT as Technology Innovation Lead, bringing with him a career spent at the cutting edge of molecular photophysics. After completing his PhD at the University of Sydney, he joined the Optoelectronics Group at the Cavendish Laboratory at the University of Cambridge, exploring the energy transfer mechanisms that sit at the very heart of CPT’s technology. Now, he’s focused on one goal: bringing photon multiplication from the lab to the real world.
How would you describe what you do to someone with no scientific background?
Imagine light as a combination of packets of energy, wherein each packet has a specific colour. Some colours are visible to us (violet, indigo, blue, green, yellow, orange, and red) but others are invisible (ultraviolet, near-infrared and infra-red). Conventional solar cells use some of these energy packets – mainly the green, red, and near-infrared ones – to generate electricity. Unfortunately the blue and ultra-violet packets of energy are wasted – converted not to electricity but heat.
At CPT, we’re developing the systems that can convert each blue (or ultra-violet) packet of energy in sunlight into two energy packets of near-infrared colour. Essentially, this doubles the number of energy packets available to solar cells to generate electricity, while also preventing excess heat generation. Overall, this leads to an improvement in the electricity generation performance of solar cell modules by up to 15%.
What makes improving solar efficiency so urgent right now?
Global solar power has grown from a niche electricity source to a major contributor over the last decade, making it the fastest-growing electricity source. Whilst consistent advances in the efficiency, stability, and affordability of solar modules has driven this growth, silicon solar cells – which make up more than 95% of today’s manufacturing capacity – are now approaching their maximum achievable efficiency limit. Most proposed solutions to overcome this are either too costly or decades away from large-scale deployment. For me, the key question is: ‘can we develop a solution to achieve more power from the same solar panel, without disrupting the solar module production lines?’
Was there a project, paper, or result that convinced you this technology could actually work?
Yes – it happened last March. I was working as a consultant at CPT, helping the team to understand the photo-physics of the photon multiplication, when we achieved something that is conventionally impossible. We demonstrated that photon multiplication can push photoluminescence quantum efficiency (PLQE) – the ratio of the number of photons emitted by a material and the number of photons absorbed – above 100%. That ceiling is normally absolute. Our result showed it could be lifted.
It was a proof of concept that validated the technical rigour of the technology, and the moment I knew I wanted to be part of what came next.
What has shaped how you think as a scientist?
It’s hard to pinpoint one moment – it’s been built up bit by bit through many experiences. I think the most important lesson I’ve taken from my career is that ‘there is no bad result’. Failed experiments bring crucial insights and most importantly, teach you the importance of perseverance. I owe a great deal to the countless failed experiments I’ve conducted – each one has helped refine how I approach research.
What drew you to CPT specifically?
CPT takes a pragmatic and non-disruptive approach – the photon multiplication materials integrate directly into existing photovoltaic modules and improve the module performance. This means that higher efficiency can be achieved from the same modules without requiring manufacturers to redesign factories or take on additional capital risk.
I am convinced that CPT’s mission ‘to make solar more powerful, without changing how it’s made’ is a technically rigorous as well as commercially realistic solution that can boost the penetration of solar cells into the energy economy.
What does CPT offer that a purely academic role couldn’t?
Working in a deep-tech startup such as CPT offers opportunities that are hard to find all together elsewhere. A team of experts working towards a shared end-goal in a fast-paced working environment, with fast feedback and quick execution. Direct engagement with industry, so you always understand what the market actually needs. And personally, the satisfaction of knowing that my efforts towards solving a scientific challenge will translate to a real product in a few years – one with the potential to improve the lives of millions of people across the globe.
What does your day-to-day work look like?
The CPT technical team essentially combines the expertise of chemists (who synthesise molecular components responsible for absorbing relevant portions of sunlight), material scientists (who fabricate nanocrystals for near-infrared light emission), and spectroscopists (who analyse the performance of the photon multiplier). I work with everyone in the team to bring all components together in a suitable medium to develop the photon multiplier system.
A good day at CPT is when we stitch the full picture of the photon multiplication process together, extracting insights into the role of each of the components in the system. This enables us to plan for optimising the performance and tuning the characteristics of the photon multipliers.
What does success look like from here?
In two years, we anticipate delivering the first photon multiplier-based silicon solar modules to the market, boosting performance by up to 15% whilst also minimising ultra-violet (UV) radiation induced damage to silicon solar modules.
In five years, the goal is large-scale integration with the solar cell fabrication industry. Going by recent International Energy Agency (IEA) forecasts, 2-3 TW of additional solar capacity will be deployed globally between 2028-2031. Our ambition is to be embedded in a meaningful share of that, potentially contributing an additional solar generational capacity of 300-500 GW/year.
And finally, what excites you most about where solar technology could go?
Growing up in a semi-rural area in the Himalayan region of northern India, I’ve watched affordable solar energy transform communities around me. From schools, to hospitals and small road-side shops, photovoltaic modules have allowed people access to energy to significantly improve their quality of life. I call this solar power-driven energy access ‘the long-waited democratisation of energy resource’.
With continued enhancements in solar module efficiency as well as battery storage technology, I foresee energy no longer being a limiting resource for communities around the world.
At CPT, we’re building the team that will take solar beyond its limits.
