In her everyday life, 46-year-old Adrienne Campbell is a science journalist, but over the past year she has been plotting to rid a small Sussex town of its fossil fuel addiction.

She is part of a group called Transition Town Lewes (TTL) which, in two days' time, will "unleash" its plan to transform Lewes from a highcarbon society to a low-carbon one.

The group is part of a rapidly growing movement of transition towns nationwide. There is even a transition village in East Sussex - Forest Row.

Next Tuesday, April 24, marks the beginning of an intense year in which all of Lewes will be asked to contribute to a "Fossil Fuel Descent Action Plan", a map of how to get from high to low in easy to manage steps.

Reducing fossil fuel consumption is crucial if we are to cut CO2 emissions but it is a very complicated matter.

Everything in our day-to-day life is intrinsically wrapped up in fossil fuel use - even the polyester mix in your T-shirt started life as a drop of oil.

TTL member Andrea Mindell, a former telecoms entrepreneur and animation producer, says: "We've been building a slow trickle of awareness and now we are launching a year-long programme of speakers and focus groups. We have set some topics for discussion to start with but then we want the community to bring their own."

From there, the seven core members hope other groups will form, each with its own unique interest - water conservation, food transport or waste disposal, for example.

At the end of the year, they will have produced a document which will set out what they want to achieve.

By the end of the first year they might ask for a council-appointed travel planner, by the end of the second year, a community allotment.

But, says Andrea, because the whole community has been involved, it will be much more comfortable than having instructions thrown down from Government.

The core members are not at ease discussing exactly what the contents of this dossier might be or what the perfect, post-oil Lewes will look like to them.

"We don't want to fill that creative space," says Adrienne enigmatically.

"We don't want to tell people our ideas and have them define Transition Town Lewes as that. We want them to come with their own ideas."

Their website is less coy, with a section entitled "What will Lewes be like?".

The views there are perhaps not as jolly as speakers and focus groups.

"The prospects for human survival in our present numbers will be dim," declares one article, showing TTL are clearly serious, despite the occasional hippie-dippy foray in to ideas about "visioning" and "clear creative spaces".

If humanity does manage to survive to the end of the year, the Fossil Fuel Descent Action Plan will be taken to the Lewes Town Council and TTL will ask for them to commit to it.

For the council, this will not come out of the blue. The group has already heard words of support from all the major political groups, MP for Lewes Constituency Norman Baker and the town and district councils.

Working with them from the beginning, points out TTLer John Webber, is the best way to ensure their commitment.

John's confidence in this tactic is well founded. He is deputy chair of Lewes District Council, a town councillor and former town mayor.

The grand plan is for Lewes to slowly change its ways and be fully prepared for any eventuality - but in ways the whole community has discussed and agreed to.

Adrienne says: "The action plan will span 20, maybe even 30 years.

Because we are planning over such a long period of time, whatever changes we make are going to be very comfortable. They may appear imperceptible but over that time they will have a large impact on emissions and fuel use."

When asked if all this is something of an anarchic two-fingered salute to a slow-moving and ineffective political system, member Ian Eiloart says it is not really a case of "screw you guys". Instead, it is about holding politicians to the encouraging noises they have already been making.

"If they don't do anything, then we'll be doing it instead," he says. "If they do take action, then it will look as if we've been doing what they said - but who cares? Success will be measured by how we cope with climate change."

The "unleashing" takes place at Lewes Town Hall on Tuesday at 8pm. Speakers include Adrienne Campbell and the full programme of events for the next year will be revealed.