Smart Energy

At a TED talk, Bill Gates offered this equation:

Total CO2 = World population x Services x Energy of each service x CO2 per unit of energy

And Mark Frauenfelder comments:

The neat thing about an equation that uses only multiplication is that if any of the four factors can be reduced to zero, then you don't have to worry about the other three factors. The total CO2 output will be zero. So which one can we make zero?

via Boing Boing.

Alas, the equation doesn’t quite get the global picture. Even if the damn breeders stopped breeding and human population were reduced to zero (hey, I can dream, right?), there would still be CO2 production from volcanoes and numerous other sources.

Seems as if Bill Gates’ equation is akin to the Windows operating system: a bit of wishful thinking built upon a false premise.

Discovery News has an interesting piece on making concrete from rice husks.

Rice husks form small cases around edible kernels of rice and are rich in silicon dioxide (SiO2), an essential ingredient in concrete. Scientists have recognized the potential value of rice husks as a building material for decades, but past attempts to burn it produced an ash too contaminated with carbon to be useful as a cement substitute.

Rajan Vempati of ChK Group, Inc. in Plano, Texas, and a team of researchers have figured out a way to make nearly carbon-free rice husk ash. Heating husks to 800 degrees centigrade (1,472 degrees Fahrenheit) in a furnace drives off carbon, leaving fine particles of nearly pure silica behind.

In recent years, concrete has become a repository for various waste products. Slag from steel mills, coal fly ash and silica fume — a leftover from the silicon metal industry — all have found second lives as replacements for carbon-belching Portland cement.

Five to 10 percent of the world’s CO2 emissions come from producing cement, so finding ways to reduce that would be a big deal. Not to mention that adding value to agricultural waste products helps support farmers.