Looks like the ancients had a better concrete than us, one that self-heals. But according to the guardian Concrete is the most destructive material on earth  So depending on whose criteria you use the results differ considerably: Even using the worst case I could find that of 1 metric ton of cement produces 1 metric ton of CO2 doesn’t even bring you to the lowest rung on the ‘Human and Natural sources of CO2 chart’ below, so 6-7% of the world emission is meaning less. What they are quoting alludes to all CO2 sources and this doesn’t even come close. If you smell a rat you would be correct.

Concrete use is a 55 billion/year industry generating some 4500 metric tons of CO2 world wide.

One shortcoming of most of those estimates is that they report only a part of the cement industry emission, the one related to the calculation process. However, IEA estimates the proportion of the process emission to be two thirds [8] while Ecofys [9] estimates it at 55%. Data from our GNR database [10] confirms the 2/3. On that basis, total emissions from the cement industry can be estimated between 6-7% of world emission.

What s the 6-7% CO2 standard? Likely it’s a fraction of the world total of 4500 tons, in other words, so what?

 

Electric cars are nor emission free. Not only are owners on the hook for emissions of equipment used etc in the manufacture of batteries etc, but each time an electric car motor runs, it emits Ozone.

 

   Part 1