Sustanability is the property of being sustainable, or, in its modern definition, the property of being continued with minimal long-term effect on the environment.
This is the objective that science is seeking. An economy that works in harmony with the environment in a long term
sustainable fashion. Is that
possible?
Depends on who you talk to.
It is certainly not possible with an economy based
primarily on fossil fuels.
The simple fact of the matter is that fossil fuel reserves are
fundamentally limited.
There is only so much petroleum in the ground and when the last drop has been purged, there will not be any more for some 65,000,000 years.
Or, at least, that is how long it has taken the natural environment to generate the present fossil fuel reserves.
It is possible that scientists might find a way to speed up the process, but the problem is that it will require more energy to make petroleum than is in the
petroleum in the first place.
Thermodynamics says that it is a losing proposition.
In the past, the heat within the Earth provided the energy for the conversion of complex organic molecules to petroleum but it is a slow process.
It was this heat that allowed the chemical conversion to fight
thermodynamics.
To quicken the pace, we would need to provide much more
energy over a shorter period.
We might be able to get this from solar-powered systems and so it is possible that with some significant technological breakthroughs, we might be able supply future generations with the
equivalent of fossil fuels.
But this will mean sacrificing energy from other parts of our economy.
This will have little or no effect on the production of carbon dioxide which accompanies the
combustion of fossil fuels.
The net result is not sustainable. Not if we want to have a minimal long-term effect on the
environment.
One of the alternatives proposed is bio-energy. It sounds friendly - after all, bio means life and that is good, right?
There are various forms of bio-energy that have been proposed. Some are actually detrimental to the environment and are not sustainable in the long run. In this category is
corn-based ethanol.
Under President Bush, there was considerable investment in production facilities that could take corn, extract the sugars, and convert the result to ethanol. However, even the strongest proponents note that it takes four litres of fossil fuels to generate five litres of ethanol by this route.
With ethanol's lower energy
content, the trade off isn't worth it. It did help American corn farmers, though, and that was the real point.
Of course, you and I are now paying a much higher price for numerous corn products from corn-on-the-cob to candies to meat, but that was to be
expected. And since corn is an annual crop, it looked like a sustainable route to energy self-sufficiency for the United States if you didn't take into account all of the other components that go into growing an acre of corn.
I would also suggest that in the category of unsustainable bio-energy are technologies based on wood and wood waste. The issue here is that the time it takes to grow trees to a
harvestable level is prohibitive.
The cycle, in this case, is somewhere between 40 and 80 years which means the economy has to remain stable over that timeline.
On top of this, wood has a fairly low density. It takes twice as much wood to produce the same amount of heat as
obtainable from gasoline.
Put another way, the carbon
dioxide footprint is twice as large. We forget that we have only been using fossil fuels for a little over 150 years.
There is lots of evidence that past civilizations deforested tracks of land that have never recovered and this led to the collapse of their economy.
There is one form of bio-energy, though, that might be
sustainable.
The growth of specific, genetically-modified plants that are rich in simple oils such as modified Canola (which is itself a genetically modified organism) or
various algae.
It will also not compete with present food production which is essential if we do not want to see the price of food sky rocket.
In the end, sustainability is essential if we are to maintain our present economy.
Personally, though, I would argue that we need to re-think our present economic models but that is for another column.
