EARLIER this year, at the World Economic Forum in Davos, Scotland was given a prestigious award for being the most forward-thinking country on the circular economy. In other words it is at the forefront of thinking about strategies for reusing waste, or rather, making one person’s rubbish into another person’s raw material.

As part of this circular economy, across Scotland people are starting to see waste in a different way. Scientists are taking demolition waste and turning it into new bricks. An amateur builder has made a home from McDonald’s rubbish. A brewer is making beer from morning rolls that would have otherwise gone in the bin. Material scientists are making paint additives out of sugar beet pulp.

Such a circular economy promises to reduce our carbon emissions drastically. As Iain Gulland, CEO of Zero Waste Scotland puts it, “By 2050, a more circular economy could reduce carbon emissions by 11 million tonnes a year… The circular economy is happening. We’re one of the first countries in the world to have a circular economy strategy, and, not only that, but things are actually happening. We have put things in place and started this shift towards a new dynamic. People are thinking of circular economy is a new revolution in Scotland, and asking how do we get involved in it? "

An Eco-house from McDonald’s waste

In 2014 Angus Carnie had an epiphany. It came after his world collapsed when, following a severe attack of convulsions, he was diagnosed with a brain tumour. “When you’re lying in a hospital bed and they tell you you’ve got a brain tumour and if it’s cancer you’ll be dead in weeks, it does rather take you on a different view of life, and you think 'right if I survive this I’m going to do something different'.”

Carnie’s thoughts turned to waste. He began to come up with the ideas that would ultimately lead him to build his own eco-house, entirely out of recycled and reused products, using anything from McDonald’s waste through to glass jars for light fittings.

While in hospital he started to ask the staff questions. As a person who had worked in the waste industry, selling shredder consoles for confidential papers, he was interested in what happened to the disposable gowns, masks, bedsheets, and other items that were discarded seemingly after one use. “Because I’m in the waste industry, I would say what happened to that?” They were, of course, incinerated.

“I started out thinking about clinical waste. All these aprons they wear once and then throw them in the bin – bedsheets and stuff like that. So I started to make blocks out of that.”

From there, he went on to consider other waste, and began to explore what he could do with McDonald's rubbish.

Carnie now lives in the house he has put together from such waste. Blue bricks made from hospital waste, light fittings from glass jars, cabin-effect logs made from discarded plastics. The fact that the hospital waste could have been contaminated doesn’t worry him. “It’s microwaved and melted and compacted all at the same time,” he says, “so there’s no danger. I’d happily have my dinner off the block”.

Recently, he says, a consultant from McDonald’s formally approached him and asked him “to come up with some community ideas of what to do with all the waste and litter that’s around.”

The house, he says, is partly designed to make people think. “Some of this plastic has a lifespan of a thousand years but people are only using it for ten minutes and then throwing it away. Let’s make it into something else.”

A brick from demolition waste

Ten years ago, when Dr Gabriela Medero first began to toy with the idea of creating the brick that looks set to revolutionise the building industry – one made mostly from demolition waste – there wasn’t so much talk about the circular economy in Scotland.

But Medero had a circular way of looking at things. A geotechnical engineer at Heriot Watt University, she was bothered by the fact that the construction industry was not only using huge quantities of raw materials that are finite resources but also producing extraordinary levels of waste. She began to working towards a solution, a circular loop in which waste could become building material once more.

Her current brick is made from 90 per cent demolition waste - plus some other materials, some “magic”, that Medero is keeping close to her chest. Although the brick has been patented, her team are just at the beginning of a commercialisation project which will ultimately lead to a spin-off company from Heriot Watt University, Kenoteq, producing the bricks.

The brick may look ordinary, but it is a game changer in an industry whose environmental impact is huge. It stands out from the main products used. Almost no raw materials are used in its manufacture. Unlike clay-fired bricks, it is not heated to extraordinary temperatures of around 1000 C. Unlike concrete blocks, it is not based around cement, whose production produces such high levels of carbon dioxide that it contributes to five per cent of global emissions.

It was in 2008, while working on a project on a historic building, that Medero started taking samples and testing. “I came up,” she says, “with this idea of taking waste from construction or demolition, from site, and reusing this to make a new building material, and taking it back to the site. It is a real circular economy concept.”

What followed was years of creating prototypes and testing them for strength. Medero observes that she is already seeing an enthusiasm in the industry for it. It’s an appetite which is only set to grow, since waste and recycling targets for Scotland and legislation are set to hugely increase the pressure on the construction industry to change their approach.

“We don’t contact people,” says Medero. “People contact us. When they got to know the idea they’re very excited. They know how this can be a game changer.”

Beer from bread

When Aulds bakery first approached Mark Hazell of craft brewery, Jaw Brew, with a batch of their leftovers, unsold morning rolls, they mentioned that they understood beer was once made from bread. Actually, it hadn’t been made that way for millennia.

As Hazell points out, although the earliest written recipe for beer, from 1800 BC, was based around bread, it was of a very different type from the modern morning roll, more like lumped together grains. Hence what Hazell then became involved in was a highly-original experiment. When he began brewing with the rolls what surprised him was that what came out was a beer with a strong taste, but which was low in alcohol, at just 2.2 per cent.

“People say,” he observes, “’Wow it is doesn’t taste like a 2.2 per cent beer.’ That’s what we managed to achieve with the bread rolls. You’ve got a beer that’s got body and texture yet isn’t full strength and so you can have a couple of pints and not worry about if you’re driving the next morning. It’s because of the bread rolls.”

Soup from farm waste

In Scotland, every year, 1.35 tonnes of food are wasted. This staggering figure, which covers household, retail and manufacturing waste, does not include what goes to waste because at a farm level – a figure which is incredibly difficult to estimate, though one regularly-used figure suggests three million tonnes across the UK annually. Next Saturday, April 29, is World Disco Soup Day, a date on which Slow Food groups across the world will, essentially, collect food waste and make soup out of it.

One such event is set to take place at the Leith Community Croft in Edinburgh. “It’s very much about using a day,” says Gillian Rodger of the Slow Food Youth Network, “to draw attention to how much food waste there is all over the world at different seasons. It’s connecting Edinburgh into a global issue. We are one of the worst countries for food waste.”

Paint from sugar beet

Ten years ago two material scientists, Dr David Hepworth and Dr Eric Whale, came up with the idea of creating a material out of root vegetable waste or by-products. The resulting product is Curran, a powder named after the Gaelic word for carrot, currently used as a strengthener in paints and coatings, but being developed for use in many other products.

Christian Kemp-Griffin, CEO of CelluComp, the Scottish company set up to manufacture the material, says that the two men were always driven by a desire to produce a sustainable product that would be desirable not just for its “feel good factor, but for the qualities of the product itself”.

He describes the early experiments. “They started off with carrots because it was easy to go to a grocery store or local farm and pick up some carrots and put them in a pot in a kitchen and make the material. But right now we’re focussed on sugar beet, because the sugar industry are producing millions of tonnes of sugar beet pulp per year and it’s much easier for us to scale our business using that.”