One of the gases used in the production of LCD TVs could
have a worse impact on global warming than all the developed
nations' coal-fired power-stations, according to a recent
Companies buying flat-screen monitors and TVs are advised
to ask their suppliers about the manufacturing process of
the screens, if they wish to avoid greater environmental impact.
The gas in question is nitrogen trifluoride (NF3)
- one tonne of which is equivalent to 17,000 tonnes of carbon
dioxide in terms of its greenhouse gas effect. It is used
in the production of LCDs and other semiconductors.
According to a report by Michael Prather - an atmospheric
chemist and director of the Environmental Institute at the
University of California, Irvine - annual production of the
gas has risen to 4,000 tonnes and is likely to double by 2009
as demand for flat screens increases.
Prather's report - published in Geophysical
Research Letters - claims that NF3
stays in the atmosphere for 550 years. The net effect of emissions
of NF3 could have a worse impact on
global warming than the CO2 emissions
of coal-fired power-stations in all the developed nations
put together, says Prather.
The gas was not classified in the Kyoto agreement because,
at the time, it was not being produced in large enough quantities
to be considered harmful. However, LCD manufacturers have
switched to using it more liberally in their processes because
it can be used as a replacement for hexafluoroethane
and sulphur hexafluoride - two perfluorocarbons which
were classified under Kyoto.
Lack of classification means companies using it will not
be monitoring its emissions, argues Prather.
TMDT - a joint venture between Toshiba and Matsushita and
one of the world's largest makers of LCDs - has already agreed
to avoid using NF3.