Saturday, October 13, 2007

Cement: 5% of Global Carbon Dioxide

From the Guardian:

There were no climate change protesters waiting to jeer as the chief executives and other senior figures of one of the world's biggest industries gathered on Wednesday. Yet they represented a business that produces more than 5% of mankind's carbon dioxide emissions. And they were in Brussels to discuss climate change.

The summit was not called by the aviation industry - that is comparatively clean in comparison. Nor was it made up of car makers, oil companies, shipping firms or any other business that has traditionally drawn the fire of green campaigners.

These chief executives deal in a more down-to-earth commodity: cement. It is the key ingredient in concrete, and one that is rapidly emerging as a major obstacle on the world's path to a low-carbon economy.

No company will make carbon-neutral cement any time soon. The manufacturing process depends on burning vast amounts of cheap coal to heat kilns to more than 1,500C. It also relies on the decomposition of limestone, a chemical change which frees carbon dioxide as a byproduct. So as demand for cement grows, for sewers, schools and hospitals as well as for luxury hotels and car parks, so will greenhouse gas emissions. Cement plants and factories across the world are projected to churn out almost 5bn tonnes of carbon dioxide annually by 2050 - 20 times as much as the government has pledged the entire UK will produce by that time....MORE