Prince Charles gave his royal seal of approval to a Renfrewshire firm today after paying a visit to learn all about their efforts to help save the planet.

The VIP guest arrived at Doosan Babcock, in Renfrew, in an electric vehicle before being shown the next generation of carbon capture technology.

Carbon Clean, which invented the CycloneCC machine, describe it as a "game changer" for the engineering industry in its ongoing work to reduce harmful emissions.

Iain Tobin, Carbon Clean's chief corporate officer, said of the royal visitor: "He was very impressed. He's genuinely interested in what we're trying to achieve, which is to bring cost-effective carbon capture technology to hard-to-abate industrial sectors."

Charles, who is also Baron of Renfrew, quizzed staff, including Aniruddha Sharma, Carbon Clean's co-founder and chief executive, and James Hall, the company's head of research, who demonstrated the vast difference in size between the old carbon capture technology and the new CycloneCC.

Carbon was previously captured using a 15-metre device, which saw the pollutant mixed with a chemical to extract it from the other gasses, but the company has now created a much smaller device.

Working like a washing machine, it uses a spinning mesh and a solvent to separate the gas, which not only means it is much smaller but it can also be more easily installed on site.

The royal visit to Renfrew, which lasted for half an hour, took place as the COP26 climate change summit continues just up the road in Glasgow.

Mr Sharma said the development of the CycloneCC, which is 10 times smaller than previous generations, would open up more space for decarbonisation.

He added: "The whole world is here and people are talking about phasing out coal.

"If cement was a country, it would be the third largest emitter of CO2 [carbon dioxide].

"Here is an example just outside the COP where people can actually come and see how the future's going to look. You can compress the size of all this equipment and scale it out."

Before leaving Doosan Babcock, Charles signed the visitors' book at the site, which shows he is not the first royal to enjoy a tour there.

In June 2010, the Princess Royal opened the firm's emissions reduction test facility.