The International Energy Agency has called for as much as $3.4 trillion US in global spending on carbon-capture technology by 2050.

The Paris-based IEA, the main energy policy adviser to 28 oil-consuming industrialized countries, made the call in a 46-page "road map" released Tuesday.

Carbon capture and storage would divert carbon dioxide from refineries and the oil sands. (CBC)

Carbon capture technology would extract greenhouse gases from power plant and factory emissions, move them by pipeline to areas where they could be injected and stored deep underground.

The IEA said governments and business need to invest in 3,400 carbon-capture projects worldwide as just one measure to cut fossil fuel emissions by half from their levels in 2005.

Even that would cover only about six per cent of the investment required to meet that target. Trillions more would be needed for investment in nuclear power, renewable energy and increased energy efficiency.

The agency said it's recommending more than a strategy for "clean coal." It said that carbon capture "must also be adopted by biomass and gas power plants; in the fuel transformation and gas processing sectors; and in emissions-intensive industrial sectors like cement, iron and steel, chemicals, and pulp and paper."

Another analysis done in 2008 by the IEA predicted that carbon dioxide emissions from the energy sector would increase by 130% above 2005 levels by 2050 without policies or constrained supply.

Now 5 carbon capture projects

There are now five commercial-scale carbon capture projects in operation in the world including the Weyburn-Midale project in Saskatchewan which takes CO2 captured at a plant in North Dakota, pipes it to a plant owned by Calgary-based EnCana where it is used to increase production from an older oilfield as well as for underground storage.

Seventy other projects are in the planning stage around the world.

The Canadian government has allocated $1.3 billion for research and development, mapping and demonstration projects and Alberta has set aside $2 billion for projects.