Camp for Climate Change Action viewed from the skies
Protesters are aiming to shut down Kingsnorth power station on the Medway estuary in Kent this weekend.
They oppose the decision of its owner, the energy company E.ON, to replace the ageing site with a brand-new coal-fired power station - the first such to be built in Britain for 30 years.
The protesters are hoping that their week-long demonstration will inspire others to follow in their green footsteps.
To get to the Camp for Climate Change Action, visitors need to negotiate at least three police checkpoints.
Officers in stab vests and purple latex gloves question and search all visitors. Other police dressed in black coveralls search roadside ditches. Overhead, a police helicopter hovers.
This is the third Camp for Climate Change Action
Similar camps were held outside Drax power station in 2006 and Heathrow airport in 2007
The camps are organised on "anarchist" principles and financed by donations
The sense of paranoia is compounded by the knowledge that on the previous day there had been stand-offs between police and protesters on the site - a sheep field about two miles from the power station - which ended in nine arrests.
That morning police announced that they had found a stash of weapons - including a knife and a "throwing star" in nearby woods - protesters deny involvement.
But once through the checkpoints and over the barrier - a makeshift stile at the bottom of a field - a whole new vista of tents and brightly-coloured flags opens up.
Climate Change Camp volunteer James Holland shows reporters around the site and points out the eco-toilets ("one for poo and one for pee"), the children's play area, the "bicycle-powered" cinema, and the 11 "neighbourhoods" - large tents where protesters from different UK localities can meet and spend time together.
Stand in a certain spot, and the power station at the focus of the protest can be glimpsed through the trees - an aging 1960s relic whose useful life, everyone admits, is nearly over, but whose replacement opponents are determined to thwart.
Kingsnorth, the protestors accept, is just one medium-sized power station, and any forced shutdown is likely to happen - if it does happen - for one day only.
The protestors have erected eco-toilets throughout the site
But, says James, it has an important "iconic" value - both for the protesters and for those who wish to see it being built.
He says: "The government and the energy companies have decided that replacing Kingsnorth will be a symbol that Britain is able to use a form of energy generation that produces massive amounts of harmful CO2.
"But we determined that our protest will also be a symbol.
"If we can stop this power station being built then we will make it much harder for the authorities to defy public pressure and build other coal-fired stations in the future."
The stage is thus set for a clash in the Kent hillsides when the demonstrators hope that their local action will help build national opposition to what they say could be a dangerous and misguided energy choice.
They are entirely candid about their tactics - and also about their willingness to act illegally if necessary.
The freely-available Climate Camp handbook predicts that a group of demonstrators will approach the power station "looking for weak points in the perimeter fence." It adds: "When the time is right, they will move together, streaming into the power station to shut it down."
Says James: "If the law protects the right of industries to destroy the planet, then it is up to people like us to prevent that - even if it means breaking the law."
It's a view that worries E.ON's Emily Highmore, who says her company has been aware of, and preparing for, Saturday's protest "for months".
"While we completely respect the protesters' right to campaign peacefully, what is not acceptable are their plans to invade the power station.
"Power stations are not adventure playgrounds, and if anyone does get in they will be putting their safety, and the safety of our workers, at risk."
"Chan" says people need to get used to life without electric kettles
Equally important is the campers' belief that their week-long protest is setting an example to others of how to lead a better life.
They maintain they are organised entirely without "leaders". Instead, all important decisions are made "consensually" through an exhaustive, and to an outsider somewhat baffling, series of meetings.
The system has impressed Claire Rogers - a housewife from the nearby village of Wainscott who has never taken part in a protest before.
She and three fellow members of a local campaigning group, Kingsnorth Climate Action Medway (KCAM), have joined the campers for the week.
"We came here to learn," she says. "What we have found is a bunch of intelligent and articulate people who have set a real example to us."
The group have been fighting to close down Kingsnorth because of concern about pollution levels - it says local childhood asthma rates are among the highest in the UK.
But protesters are equally determined that a replacement will not be built. They reject E.ON's estimate that the new power station will be 20% more efficient.
Visitors to the Climate Camp are subjected to police searches
"All that means is that more coal will be burned - and the pollution will remain," says KCAM member Simon Marchant.
Says Emily Highmore: "No-one actually knows how much coal we will need to burn when the new power station is built - that depends on market conditions."
The company is also stressing that it intends to close down an additional two fossil fuel power stations elsewhere in the UK - one of which will be replaced by a more carbon-friendly gas-fuelled station.
The Camp boast that no CO2-producing fossil fuel energy is used to make electricity on the site.
A total of 18 solar panel arrays, plus a wind turbine, is supposed to take care of all the camp's power needs - the dozen laptops in the media tent; the PA system in the main meeting tent and mobile phone chargers.
But when the sun fails - as it did on this day - so the power drops. Signs appeared in the media tent informing that the camp was on "red" status - meaning that the laptops and other electrical devices could not be used.
It neatly encapsulated Britain's future energy dilemma - do we rely totally on renewable energy sources and risk the lights going off when the sun goes in or winds and waves fail?
Or do we continue to burn fossil fuels that produce CO2 emissions, and risk harming the environment?
For "Chan" - the solar power engineer who maintains the arrays around the site - the solution is tough, but simple: use renewables, encourage everyone to use less energy, and if necessary accept that standards of living will fall.
"That means no electric kettles or extra TVs," he says. "The alternative is the end of the human species."
Other climate campers are more circumspect, maintaining that energy conservation - better home insulation, more efficient power generation - will provide a large part of the answer.
But one camp organiser, Alex Harvey, is in no doubt that changing the way Britain produces and uses its energy will involve a fundamental rethink of everyone's priorities.
She is not afraid to describe herself as a revolutionary - although she accepts that the term has for others unfortunate "historical connotations".
"We are about challenging the growth economy," she says. "We are about pushing for radical social change, about the whole way the economy works.
"But I have to admit - we don't yet have a blueprint for a peaceful, just and sustainable society."
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