Back in April, Nick Clegg restated government resolve to pursue ambitious environmental goals. The Deputy Prime Minister rebuffed rumours that the credit crunch had killed environmentalism. On the contrary, "going green has never made so much sense" and sustainability, in fact, coincides with economic recovery; "lean times can be green times", he repeated. Clegg called his idea "environmental thrift", which is basically just good housekeeping. Indeed, it seems quite possible that Mr Clegg's speech was inspired by our grandmothers war-time abilities to make a little go a long very way. And good on him for that. The global economy has a thing or two to learn from sound home economics.

Mr Clegg's position makes a lot of sense, but he's missing one important factor in the equation. His speech draws our attention to two areas of government action: cutting consumer energy consumption to reduce emissions and alleviate financial pressure on households and building up low carbon sectors to create a competitive green industry for Britain's economic future. That's all well and good, but it misses the crux of the matter. Clegg's proposals are top-down initiatives. Real "environmental thrift", honest, hand-on, efficient and effective housekeeping, is not happening top-down, through policy. It's happening bottom-up, through consumers.

You may already have heard of collaborative consumption: a more efficient economic model that reduces our carbon footprint and level of spending by sharing resources within our communities. Spearheaded by Rachel Botsman of TED Talk fame, co-author of What's Mine Is Yours, How collaborative consumption is changing the way we live, it was named one of Time Magazines 10 ideas that will change the world in 2010.

Collcons, the insiders' affectionate name for collaborative consumption, is a grassroots phenomenon that affects our consumer behaviour everyday, at every level of our lives. Another name for it is the sharing economy. You can see it at work in all the major industries: apparel (rent budget-busting dresses for £15 on wishwantwear.com), money (lend to an individual on Zopa.com and get better rates than at the bank), workspaces (don't work, co-work in a shared space like The Hub), accommodation (for your next holiday, save yourself the hotel bills and swap your home on LoveHomeSwap.com), etc. In the travel market, my own company connects drivers with empty seats to passengers looking for a ride on BlaBlaCar.com.

Another good example is Landshare.net, a network of people who have banded together to cultivate unused land. Not all land-owners have the time or energy to garden--and not all the people who would like to home grow their veggies have land available. By connecting them, Landshare is very literally increasing our lands productivity--at zero cost. What government policy can beat that as a result?

Enthusiasts speak of 'the sharing revolution'. However you refer to it, collaborative consumption is a people's groundswell that promotes more efficient and sustainable outcomes. Collaborative lifestyles, spontaneously emerging in groups of savvy consumers around the world and across the UK, are the real driving force behind environmental thrift, not Mister Clegg's policy statements.

As the country grits its teeth to face the impact of austerity, economic constraints are being seized by disillusioned consumers as an opportunity for reinvention; the sharing economy is a bona fide silver lining.

Today is National Sharing Day. Major players in this emerging sector and forward-thinking citizens across the UK are getting together to spread the word about the economic transformation we are part of. It's the official launch day of a new non-profit organisation called The People Who Share, supporting the growth of the sharing economy in Britain. At BlaBlaCar we've released an infographic announcing that our car sharing platform now has over one million seats available. Together, we're celebrating a new vision of society where, in the words of the Deputy Prime Minister, "for first time ever our economic and environmental mantras are exactly the same: Waste not, want not".

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