Each year, many countries meet to discuss climate issues happening around the globe. This year, COP 22 (Conference of the Parties) has been held in Marrakech, Morocco. Over 197 parties were present, including Canada. At the conference, Canada pledged to 80% reduction of its greenhouse gas emissions by 2050 compared to what they were in 2005. That is such a high percentage; is it possible to achieve it in the next 34 years?
Roads, houses, condominiums buildings… They can all be, or are, built from concrete. What exactly is concrete? It is simple: water, additives, aggregate and cement. At this moment, the problem would be that CO2 coming from cement production represents 90% of greenhouse gas emissions. Looking only at this statistic, the first question coming to our mind is: “Why do we keep producing it”? Well, it is simple! Once poured, concrete reabsorbs 43% of the CO2 released in its production. If the cement manufacturing industries would impound CO2 at the moment of its emission, the percentage could even increase to 100%.
In addition to reabsorbing some of its own emissions, concrete has others advantages. Indeed, at this period of the year, when temperature begins to drop, concrete becomes an excellent material to preserve heat because of its thermal mass. The thicker, the better! In the summer, the concrete will absorb the coolness during the night and conduct it during the day. The same principle applies in winter: during the day the concrete absorbs heat from the sun and the heat transfer takes place when night comes. Winter or summer, this concept makes happy consumers because of money savings and a healthier planet because of the energy savings!
So, is concrete really polluting?