The Prince of Wales brought his environmental and whisky interests together as he opened a biomass plant and a whisky bottling centre at a 173-year-old distillery on Tuesday.
Charles, known as the Duke of Rothesay in Scotland, was at Glen Grant distillery and the Helius Corde plant in Rothes, Moray at the start of a three-day visit to the north of Scotland.
He met staff and toured the distillery to see how the whisky is matured and bottled.
Wearing a Stuart Hunting kilt and green tweed jacket, Charles unveiled a plaque on a pyramid of whisky barrels outside the distillery and quipped: "Is this the emergency supply?"
The new bottling plant produces 2000 bottles an hour, which are mainly exported to mainland Europe and Asia.
Glen Grant managing director Dennis Malcolm said Charles's visit is the first by a member of the royal family in around 50 years.
"Our last royal visit was by Princess Margaret in 1959 so it was nice to have another member of the family up today to mark the new site," he said.
"The Prince is certainly a big whisky fan and I think he asked more questions about the bottling hall than I've done. He wanted to know how many bottles we can produce in an hour, what we do if it breaks down and where all the bottles go."
At the end of the tour Charles chatted with children from the nearby Rothes primary and nursery school.
Senior nursery nurse May Wilson said the children watched a video earlier in the day, just to make sure they recognise him.
"Most of the nursery children only know about princes from fairytales, so this is a first to actually meet a royal and they loved it," she said.
"He asked them if they enjoyed their Easter holidays and joked that they will all have to wait a long time before they can try whisky."
Earlier in the day Charles had a tour and opened the new Helius Corde heat and power biomass plant, designed to recycle the waste created from making whisky.
It takes pot ale and draff by-product from 12 distilleries around Speyside and recycles it as animal feed. It also creates electricity by burning draff and woodchip.
Operators say it will generate 8.32MW of electricity every year which will be sent back to the National Grid, enough to power 9000 homes.
Alan Lyons, chairman of Helius Corde, said: "The Prince was very much into the fact that we're using recycled woodchip and with our environmental credentials as we aim to maintain low C02 levels. It was a delight to have him here and he really took time to speak to all the workers and showed an interest in what they do and the whole process of the plant."
During the visit to the neighbouring Rothes businesses, Charles was accompanied by Scotch Whisky Association chief executive Gavin Hewitt, who organised the tour.
Mr Hewitt said: "It's been an excellent day and the opening of these new sites shows the strength of the industry, and is great for Rothes and Speyside.
"I was asked to suggest opportunities for a royal visit and I thought this was the ideal site as it has an environmental aspect as well as the traditional whisky making. I knew Prince Charles had a great interest in both those areas and he was particularly impressed by the Helius plant and was fascinated by how it worked.
"He thoroughly enjoyed his visit and always likes to show his support for this particular Scottish industry.
"There were a couple of bottles given to him, one at each site, and I could see the delight in his eye and no doubt he'll add it to his cabinet and can enjoy a wee dram when he puts his feet up later."