The global temperature could increase by six degrees centigrade by2100, with dramatic implications for all countries, the IEA said.
"The challenge for allcountries is to put in motion a transition to a more secure,lower-carbon energy supply and demand, without undermining economicgrowth," the IEA said. "An energy technology revolution is needed toset us on a more sustainable energy path."
On the supply side, theIEA said measures to cut greenhouse gas emissions include nuclear powerplants, onshore and offshore wind, solar energy and advancedtechnologies for coal gasification.
The IEA alsocited investments in efficiency to curb demand: energy sippingappliances and heat pumps, solar space and water heating, electric andplug-in vehicles and hydrogen fuel cell cars.
"There is currently nosingle technology solution that can lead to a sustainable energy future-- all energy technologies must contribute," the IEA said.
In the U.S. all ofthese measures are currently under development, with the U.S. congressdebating subsidies for solar and wind as well as measures to cut CO2emissions either by taxing greenhouse gas producers or setting up asystem to trade emission credits.
This week debatelaunched in the U.S. Senate over a cap and trade system, which hasreceived support over the years from both presumptive major partypresidential candidates, Sen. John McCain and Sen. Barak Obama.
Gary Hart, marketanalyst for ICAP Energy, a brokerage and trading firm, said theconsensus view from some 200 emissions traders and executives at theCarbon Finance North America 2008 conference this week is that the U.S.appears to be moving toward a major cap and trade law some time nextyear.
Even if a law is passednext year, it probably won't be enacted until 2012 or later to giveindustrial clients time to adapt to the changes, he said.
The U.S. led the worldwith its cap and trade system for sulfur dioxide and other acid-rainpollutants with landmark legislation in 1990.
"In some ways it's likeDéjà vu all over again," Hart said. "Some of the talks amount to thesame debate that Congress had over acid rain. This is not somethingbrand new that congress has taken on. They were able to amend the CleanAir Act in 1990."
However, one differencenow is the lack of technology to directly take C02 out of the air--unlike scrubbers and other machinery available to reduce acidrain-causing emissions.
Instead, companies willhave to purchase carbon offsets -- measures that help reduce CO2emissions other ways, such as solar energy, geothermal, wind, and evencapping animal manure and burning off the methane produced from it.
"The alternative energy business could see huge investments," Hart said.
Down the road, technology will also be developed to take C02 out of theair by pumping it into the ground, but that technique is still in thetesting phase, he sad.
