PARIS • The organisers of the United Nations climate conference starting in Paris in a month's time face an unenviable task.

They must welcome tens of thousands of participants to a site near the French capital, house them, feed and transport them, and do so in the most exemplary fashion, ecologically, with the world's media dissecting every aspect of the event's organisation.

With US President Barack Obama and his Chinese counterpart Xi Jinping among more than 80 world leaders attending the 21st United Nations Climate Change Conference, security will also be tight when proceedings open on Nov 30.

World leaders are coming together to try and reach agreement on tackling climate change, with the goal of capping warming at 2 deg C over pre-Industrial Revolution levels. This conference is "exceptional in every way, because of its duration (two weeks), the seriousness of what is at stake, and because it brings together a great number of participants", said the official in charge, Mr Pierre-Henri Guignard.

A temporary town is being built at Le Bourget near Paris to host the event, with organisers claiming it has been planned according to the principles of sustainable development. The 17ha site includes 60 buildings that house meeting rooms, restaurants, shops, a bank, a post office, a 24-hour media centre for 3,000 journalists and medical facilities.

The estimated 21,000 tonnes of greenhouse gases expected to be produced by the site will be offset after the conference by projects in the Southern Hemisphere.

French company Engie is supplying a condensing boiler that recovers the lost energy generated in the traditional combustion process, a technique the firm says delivers greatly increased efficiency.

There will also be so-called "wind trees" - effectively windmills - while Ikea will supply furniture and Google the computer screens, with the Renault-Nissan group providing 200 electric cars.

The 900 trees sacrificed for the wood in the giant room that will host the plenary sessions for 2,000 delegates will be replanted.

"The materials we are using have already been used, we are using them again and they will be used once again after the COP (Conference of Parties)," said Mr Patrick Bazanan, of Decoral, the company building part of the site.

The collection of restaurants, snack stands, cafes and food trucks have been ordered to cut down on wasteful packaging.

By using biodegradable and returnable glasses and cups, two million plastic cups will be saved from the waste containers. All cutlery will also be made from biodegradable materials, said Mr Jean-Francois Camarty from catering firm Elior.

Recycling bins will be situated throughout the site and electric-powered vehicles will pick up the waste.

To reach the site, delegates are being urged to use public transport, and are being given free travel passes as an incentive.

French national rail company SNCF has taken measures to transport an additional 70,000 people every day on the suburban rail line that links the centre of the capital with Le Bourget.

AGENCE FRANCE-PRESSE