Article#5 Cement and concrete sustainability credentials'Focus on the Concrete Centre Jan/Feb '06 Issue'

Society can no longer look at the environment as a free resource due to the impact of climate change on our planet. In the building industry embodied energy has been introduced which lead to the calculations of “whole life” impact an overall building.
Concrete is the most widely consumed material due to its flexibility and durability; it is only second to water.
The cement industry has been making investigations about how to reduce the energy consumption of their product and CO2 emissions. Since 2004 the energy consumption has been reduced by 21.2%. It has begun to use secondary fuels such as water solvents and non fossil fuels used on tyres. This not only reduces landfill but also helps with the environment.
The embodied energy of construction materials is insignificant when compared to the energy consumed of the buildings lifetime. Heating, cooling and lighting, produces 90% of buildings energy. It is here that concrete becomes an asset because of the high thermal mass the building energy used when in use can be greatly reduced.
The thermal capacity of concrete allows it to absorb and store heat and then later on radiate heat which stabilisers the internal temperature. Good ventilation, thermal mass, exposed concrete have helped to improve productivity by 16%.
The concrete industry are actively trying to push the use of recycled concrete to help reduce the use of natural resources such as sand gravel and crushed rock. Concrete is 100% recyclable.
Pre-cast and ready mix concrete companies also can be ecologically friendly by using pulverised-fuel ash, which is a product recycled from coal-burning power stations. Pulverised-fuel ash allows 70% of cement to replaced in concrete.