“It’s a unique architecture. Rather than sandwiching solar generating materials between glass or other substrates, we take a polymer substrate and in it we create microstructures that are smaller than a human hair to create a dense pattern of solar cells – it’s the same process used to make the holograms you see on credit cards.”
What is Power Roll?
Neil holds up a small square of card no bigger than a credit card to the camera. “This is about 0.3mm thick and weighs roughly 500g/m2 when fully installed. In this square there are 8,000 individual solar cells connected into 500 modules. It’s a completely new way to make pv.”
What are the benefits?
“By using this manufacturing approach, we remove many steps required to create traditional solar panels which takes the cost of manufacture to a very low-level at large scale. Traditional pv technologies work out at around $0.20-0.25/Watt, whereas we expect ours to be around $0.03/Watt to manufacture – the lowest manufactured cost of any solar technology.
“What’s more, because it’s so thin and lightweight it opens up applications that can’t be accessed by current technology. There are a lot of markets that are unsuitable for traditional solar modules either because they can’t be easily accessed or because solar modules are too heavy or too rigid; for example, non-load bearing roofs, or unusual shaped structures.”
It’s certainly an exciting proposition. The Power Roll website features idealised imagery of cities, towns and villages all cloaked in Power Roll. It’s a bold vision of the future, but is it too good to be true?
Are there any downsides?
“I always describe the golden triangle of solar technology as ‘cost, life and efficiency’. The new tandem cells [silicon and perovskite] are pushing efficiency with some impact on cost. We’re primarily focussed on reducing cost. Current silicon pv has efficiency of around 20% and tandem cells up to around 30%. We’re currently achieving 11% and have a roadmap to get up to between 16 and 20%, but it’s at a far lower cost and, because it’s thin and flexible, our film can go where others can’t, so we open up the building envelope further.”
What’s the life expectancy & payback period?
“It looks incredibly flimsy, but we’ve ran it over in a car and hit it with hammers without causing any damage. Because the microgrooves are so tiny (2 microns), it’s actually very durable. We have put a conservative estimate of 15 years on the film, which is shorter than traditional PV, but because the cost is so low the payback is so short that you still get a significant return on investment and, when you look at the cost of energy over the lifetime, even with replacement in year 15, the levelised cost of energy is around half that of current best-in-class PV.”
With all the gleaming, Power Roll covered walls, roofs, buses and lorries portrayed on the website, does Neil have a vision of the most likely applications or best fit for the technology?
Where do you see Power Roll being used?
“Mid-range to high rise blocks, warehouses, factories, car ports those are the areas we see it being deployed in the UK. As you can genuinely carry 25kW of product under your arm, there is an ease of rolling it out, adhering it to a surface and connecting to the invertors that is massively beneficial for large scale applications, but we are looking for installers and integrators of technology to work with to explore what the opportunities might be because we’ve only scratched the surface with where this technology can go. It might be that there are installers out there who are thinking ‘well, could it do this?’
If you have any ideas in mind or would like to discuss the opportunities further, you can get in touch with Neil at firstname.lastname@example.org. Power Roll is currently coming out of the development phase and into the commercialisation with £6m in funds raised to build a pilot plant, which should be operational by the middle of this year.