Nature 424, 251 (17 July 2003) | doi:10.1038/424251a

Virtual solution to carbon cost of conferences

David S. Reay1

  1. School of Geosciences, Ecology and Resource Management, University of Edinburgh, Darwin Building, Mayfield Road, Edinburgh EH9 3JU, UK


Improved technology is making virtual meetings more like real ones, without the flights.


Every year, many thousands of scientists jet off to a host of destinations all around the world to attend conferences. Emissions of carbon dioxide, a greenhouse gas, from air travel are growing at an alarming rate. In 1992, at 500 million tonnes, they constituted about 13% of all CO2 emissions from transportation sources. By 2050, the Intergovernmental Panel on Climate Change estimates that aircraft emissions will triple to 1.5 billion tonnes of CO2 per year.

During the past few years, an increasing number of conference organizers have recognized this pollution problem and have attempted to mitigate their climate impact (see, for example, Some recent environmental conferences have aimed to offset the greenhouse-gas emissions caused by their participants' travel by funding tree-planting schemes. Others strive to be entirely 'carbon neutral', sourcing their electricity from renewable sources, and others even buy carbon credits to offset conference-related emissions. Now, a new technology, the Access Grid system (, is promising to change the face of our conferencing habits.

Access Grid is similar to video conferencing but lets groups from numerous different locations communicate among themselves at one time. Instead of only being able to see the speaker (a limitation of traditional video conferencing), delegates can also see and talk to other groups of delegates — in the next town, in another country or on a different continent. Speakers can manipulate their presentations to all viewers simultaneously so that, as each one moves through the slides on his or her own screen, all the viewers' screens are also updated.

A key aim of Access Grid is to solve the problems faced by many researchers in the developing world, who are prevented from attending international conferences by economic constraints. There is, however, a significant start-up cost of around US$25,000 for the technology, and few locations in the developing world are currently able to meet the requirement of Access Grid conferences for broadband network access (greater than 1Mb per second minimum bandwidth).

Several international conferences have already successfully used the Access Grid, with many more such meetings planned and an ever-growing number of institutions able to co-host conferences. The huge environmental dividend of virtual conferencing is demonstrated by the estimate for a recent genomics meeting, where travel-related CO2 emissions of the order of 900 tonnes were avoided (, or see W. A. Valdivia-Granda, E. L. Deckard & W. Perrizo Proc. Virt. Conf. Genom. Bioinf. 1, 1–3; 2002).

The combination of this new technology with ever-improving video and sound (for example, Hewlett-Packard's new Coliseum immersive teleconferencing system) means that the old objection — that virtual conferences are impractical and impersonal — is rapidly breaking down. Though many of us may feel it is unfair to deprive ourselves of all-expenses-paid international trips and the outside-meeting socializing common to most conferences, we should not ignore the environmental impact of these meetings. 'Real world' conferences will always have a place, but given the huge number of international conferences, even limited use of Access Grid virtual conferencing has the potential to reduce CO2 emissions by many thousands of tonnes.