Interesting Concrete Perspective on Emissions

I have been stressing the point, that carbon emissions reduction is a blatant attack on growing economies. The main reason, is that growing economies depend on increasing energy supplies, and most of our power plants are dependent on fossil fuels. There's been a lot of hype on developing alternative and renewable energy sources, but most of those technologies are not as efficient in the power output to land-use or cost ratios. Nuclear power is hamstrung by environmental regulation. So, how about letting industry be more energy efficient as a means to cutting carbon emissions? A novel approach is discussed in this LiveScience article: reducing the energy required to make cement, by replacing calcium with magnesium. Since a cement structure with magnesium requires less heat to manufacture than the usual lime and clay matrix, energy use, and costs, go down. Unfortunately, magnesium is an earth metal, which means it is highly reactive and must be handled as a hazardous substance. Poor concrete manufacture could have magnesium seeping into the ground, and then we would have health concerns like we do over mercury and lead. Also, I wish the writer of the article would cite where he got the figure that cement manufacturing accounts for ten percent of carbon dioxide emissions. Seems like too round of a figure. If a safer metal can be used to replace calcium, this idea might have legs, otherwise, it's just another dream to be put aside with the new industry that buries carbon dioxide under the ocean floor.