Sustaining Future

Wednesday, November 28, 2007

Growth and Substainability

I was watching a video by Dr. Albert A. Bartlett, Professor Emeritus made in 1994. It seems to me that the message Prof Bartlett gave 13 years ago has gone unnoticed.

There are a few messages that strike me as so simple and wonder why we cannot understand.

1. We have been and are still, overly concerned about growth - which in fact will lead to the inevitable exhaustion of natural resources.

2. A bit of mathematics to help understand this. Roughly, the "doubling" time of any growth can be calculated by this formula 70/growth%. So, if the rate of growth is 7% per year, the quantity will double in about 10 years. That is if the world's population growth is 2.2%, we can expect the world population to double in 32 years. Assuming our average life span to be 70 years, we shall see the world population multiply by 4.

3. So is the rate of consumption. The current estimate is that world energy consumption will growth by 2.6%, which I believe is an under-estimation. (Population is growing at 2.2% already! What about the better living standard?) Energy consumption will double in 27 years.

4. Natural resources such as oil and coal are finite resources. How long do we have when we realised that we are running out of such resources before exhaustion of the resource? Suppose we have already used up almost half of ALL the world reserve in oil and coal, then we have about 27 years before exhaustion if we continue with the current rate of growth. That's 2034! How many countries are prepared to switch to completely renewable energy by 2034? Not much, I suppose.

[You may argue with the numbers such as the growth rate, the percentage we have already consumed, but the story is the same. The big question is "Is the human race prepared for energy shortage within our next 80 years - about the life span of our children?"]

Those with better source of the numbers, please leave your numbers in the comment (together with source please). Please also calculate how long before exhaustion we still have.


Tuesday, November 20, 2007

Treat Water, Make Energy

I am advocating the use of "by-production management" instead of "waste management" because this will shift our focus of the way of utilising the "waste".

Here is a good example. A single-chamber fuel-cell which uses "waste-water" as its energy source.

The single-chambered microbial fuel cell is essentially a plexiglass cylinder about the size of a soda bottle. Inside are eight graphite anodes (or negative electrodes), upon which the bacteria attach, and a hollow central cathode (or positive electrode). Electrons flow along a circuit wired from the anode to the cathode.

A steady flow of wastewater pumped into the chamber feeds the bacteria. Bacterial digestion of the wastewater's organic matter unleashes electrons into the electrical circuit and positively charged hydrogen ions into the solution. Those ions reduce the solution's oxygen demand, a key goal of wastewater treatment. The hydrogen ions also pass through a proton-exchange membrane to reach the cathode. Meanwhile, a hollow tube within the cylinder contains the cathode, which is exposed to air. At the cathode, oxygen from the air, hydrogen ions coming through the membrane and the electrons coming down the circuit combine to create water.


The single-chamber design is important, he said, because it facilitates a "continuous flow-through system," a design consistent with existing treatment systems.

By introducing air passively through the tube within the cathode layer, this model also greatly reduces the need for more aggressive – and energy-demanding – aeration schemes to treat the wastewater. Thus, as it creates electricity, it also reduces the need for it.

This is turning a cost-center (treating waste water) into a profit-center. Even better is the size of the device. It can be installed at our home and let's us reduce our energy bill. WoW!


Saturday, November 03, 2007

Trash to Treasure

This video shows how IBM converts rejected wafers (which is a "waste") into valuable product for solar cells. Another "By-product" concept which helps IBM create over 1M per year!