This Monday marks the start of the fifth annual Enterprise Week in the UK. An extended hootenanny for aspiring entrepreneurs, it’s backed by Gordon Brown, and last year attracted more than 500,000 young people to thousands of events nationwide with the aim of encouraging them to see the world through entrepreneurial eyes and educating them in how best to do so.

Within all this, though, one day, Thursday, is set aside and dedicated to the idea of “social enterprise”. In the simplest terms, social enterprise is what happens when you cross Dragons’ Den with Live Earth: profit-making businesses that place the tackling of a social or environmental problem at their core: think Jamie Oliver’s Fifteen restaurant employing young people from disadvantaged backgrounds; The Big Issue magazine supporting the homeless; or Fairtrade and sustainable food producers such as Cafédirect or Divine Chocolate). These aren’t charities, because they all aim to turn a profit which they can then reinvest to sustain and develop change. And nor are they niche. There are, the Annual Survey of Small Businesses reports, 55,000 social enterprises in the UK, with a combined turnover of £27 billion, and today, 1.3 million people consider themselves to be social entrepreneurs.

It’s a figure that will continue to rise. In September this year, social enterprise became part of the core syllabus for GCSE Business Studies, which should only add to the sense that here is a commercial model that will continue to be pioneered by the young, for whom aspiration to entrepreneurship has never been greater, nor the problems facing the world they will inherit in such clear focus.

Change your pants: Green Knickers

The first piece of underwear Sarah Lucy Smith and Rose Clearly-Southwood came up with under the Green Knickers banner was designed to be informative, as well as environmentally sound. “They were our ‘global warming knickers’,” grins Smith. “We made them with heat-reactive ink and organic cotton. When they warmed up, you could see [an image of] the sea overcoming the land.”

As a product, it just about nails the blend of humour and entrepreneurial vim cut with steely commitment to sustainable and fair-trade principles that the two 26-year-olds have traded off since they set up in 2006. Visit their website (www.greenknickers.org) and you can browse both men’s and women’s underwear produced from a mix of bamboo, organic cotton, hemp, silk or reclaimed and recycled fabrics ranging from old curtains to duvets. Some are comfortable and some are sexy, the pair insist. “And they’re all fitted around real women and real bottoms… we don’t model them on size-8s.”

What began as a hobby, stemming from what Smith learned as an eco-design student at Goldsmiths College, became a working business when disillusionment about their roles in commercial fashion (Smith as an underwear designer, Clearly-Southwood as a merchandiser) coincided with a growing public understanding of organic fashion. “Using underwear design to actually make a difference in the world, which would have seemed a ridiculous idea not long ago, suddenly became a genius idea,” beams Smith. “Though, at first, people would ask if ‘organic’ meant they could eat them.” “Or if they could smoke the hemp ones,” adds Clearly-Southwood.

Today, their cotton knickers are produced from certified organic cotton, and made by a women’s cooperative in India. They’re at pains to stress to their customers that it’s not just the finished product they should be scrutinising, but the whole supply chain: 20,000 people are poisoned by pesticides used to grow non-organic cotton each year, they explain, and every item made by the cooperative means one less item produced in a sweatshop.

At the same time, they know there’s no point in trying to build a successful business on worthy intentions alone: “It’s so important that ethical clothes are good, if not better, than what’s available on the high street, because that’s the only way people are going to get on board,” insists Smith. “I think you have to be 100 per cent entrepreneurial to make a business work, but to get out of bed in the morning, you have to have a purpose.”

Reinventing the fridge: Emily Cummins

Emily Cummins says it can be difficult working out how best to describe herself. The 21-year-old from Skipton, North Yorkshire, may be a business management student with her own line of products (www.emilycummins.co.uk), but “entrepreneur” seems a touch too slick. And although she invented her products herself, she wouldn’t feel right calling herself anything as technical as “engineer”, because she “only studied physics at GCSE, not A level”. Instead, she settles on “problem solver”, and it’s soon clear why.

While still at school, Cummins won a Sustainable Design Award for her plans for an innovative water-bucket carrier for use in Africa. “At the awards ceremony, there was a speaker talking about the effects of global warming, and people’s impact on the world,” she remembers. “I was shocked, in a way. When we think about design, we tend to think about luxury products… bigger TVs and stuff. But I decided to make something that would reduce the amount of fossil fuels being burnt, which is why I started to design my fridge.”

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