Researchers reveal solar-powered tiles that can create enough energy to power entire cities

A computer generated image of what a walkway by the Arabian Gulf in Doha, Qatar could look like

Solar-powered tiles could soon line pavements, harnessing the sun's energy to power our cities. 

At least that's the vision of Scottish scientists who are working on creating paving tiles that converts energy from the sun into electricity.

Scientists say the tiles are tough enough to withstand pedestrian traffic and waterproof enough to survive rainy weather.

A team, including scientists at Glasgow Caledonian University, have invented the energy-producing tile which in their hundreds could line whole pavements.

On sunny days the tiles could produce 200 watts of energy per square metre, and about 150 watts if cloudy.

Lead researcher Dr Azmy Gowaid and his team received £75,000 ($100,000) funding when organisers of the 2022 World Cup in Qatar invited competitive bids for innovative designs that could deliver a tournament powered by as much renewable energy as possible.

The team of five scientists has already conducted a pilot study at the Al Shamal stadium in Qatar. 

They are planning to demonstrate its prototype either outside one of the World Cup venues or in a fan zone.

Dr Gowaid, who is a lecturer in Power Electronics at Glasgow Caledonian University, said: 'Qatar has a drive to deliver as much as possible a sustainable tournament and so they are keen to get some sort of renewable technology running alongside the tournament.'

Prior to that, Dr Gowaid's project, called PVTopia, will be rolled out in the hotter climates of North Africa and the Middle East. 

The tile’s innovative cooling system that prevents heat damage will be put to the test under severe surface temperatures reaching 80°C. 

The tile, which comes at regular paving stone sizes, could light up the buildings we live and work in. Pictured is the same bit of pavement without solar panels. Pictured is the same walkway by the Arabian Gulf in Doha, Qatar as it currently looks 

Pictured are early laboratory-test prototypes of the PVTopia solar tile. It is made of a tough resin and contains photovoltaic cells which convert the energy from the sun into a flow of electrons

Dr Gowaid said: 'This is about cities generating their own energy rather than supplying the whole country's needs.

'You're looking – for a start - at the owners of residential houses or small commercial shops generating their energy on their own.

'If this is deployed amongst thousands and thousands of people then eventually the overall impact is going to relieve the (national) grid significantly.' 

The spread of solar energy means roof space will be a diminishing resource, Dr Gowaid said. 

'Meanwhile cities are getting more dense as electricity demand rises amid serious climate change challenges', he said.  

Scientists say the tiles are tough enough to withstand pedestrian traffic, and waterproof to deal with our rainy weather. Pictured is an artist's impression of walkable solar tiles laid in St Enoch pedestrian square in Glasgow

 On sunny days the tiles could produce 200 watts of energy per square metre, and about 150 watts if cloudy. Pictured is St Enoch pedestrian square in Glasgow as it currently looks

Dr Gowaid points out that while the costs of the tiles can be double that of normal paving, the energy they produce means the installation costs will soon be met.

Once the break-even point is reached the tiles will continue producing power for another 15-20 years – for free.

Dr Gowaid said 'At low scale, say on a pavement of a street or general pedestrian walkways, the installation cost would be more than double the cost of paving stones. 

'However, the generated revenue by feeding to street lighting, traffic systems, or simply selling energy to the electricity provider means the walkable solar pavement will be much cheaper than paving stones over the expected lifetime'.

The team of five scientists has already conducted a pilot study at the Al Shamal stadium in Qatar. Pictured are the tiles during lab tests

Researchers are planning to demonstrate its prototype either outside one of the World Cup venues or in a fan zone. Pictured is a prototype 

Traditional solar panels are mostly limited to slanting roofs as they cannot be walked on and render any space they lie on useless for other purposes.

To generate energy from flat rooftops that are normally used for other purposes, walkable solar tiles are a potential alternative solution.

As well as being made of a tough epoxy resin the tiles are also fitted in a hard frame from recyclable material that makes it very durable.

'Should this prove successful, it is our dream that this product can eventually be installed at mass scale anywhere in the world – even in rainy old Glasgow,' said Dr Gowaid.

'We want to see the tiles contribute to the energy supply mix of stadia, other sporting facilities and beyond to public squares, pavements, schools and university campuses'.

Fatma Al Numai, of the Qatar tournament's Supreme Committee for Delivery and Legacy, said: 'We set up a legacy programme for exactly this reason – to support entrepreneurs, innovators and scientists like Dr Gowaid.

'What the team at PVTopia are doing is incredible and we can't wait to see everything in action at the World Cup'.

HOW MIGHT SOLAR PANELS ALSO GENERATE ENERGY FROM RAIN?

A new type of solar panel cell that generates energy from rain as well as the sun's rays could be used in countries that see little sunshine.

A prototype recently developed by Chinese scientists works like a normal silicon cell with an extra power generator layered on top.

In the rain, the cell switches over to this 'triboelectric nanogenerator' (Teng), which converts the downward force exerted by raindrops into electricity. 

Because the plastics used to make the Teng are transparent, the solar cell could still generate energy from sunlight, as well as falling raindrops.

The physics behind the hybrid device involves the transfer of electrons between two conducting materials when they make contact.

When raindrops fall on the cell, they compress the upper Teng layer, generating a current of electrons that flows to an electrode below.

It could be useful in areas that see little sunshine, such as the UK, which can produce up to 8GW of solar power on sunny days - a quarter of the nation's power demand - but just 1GW of power on dull days in winter.