Sustainable Energy Is Unsustainable... currently

One of the points that I always try and make when I am talking to people about alternative energy is that the infrastructure to support it doesn't exist. A point that I guess I was vaguely aware of but hadn't really thought about is that many of the green technologies rely on relatively rare elements that make them unsustainable.

That point is made in this NewScientist article:

Although scientists are agreed that we must cut carbon emissions from transport and electricity generation to prevent the globe's climate becoming hotter, and more unpredictable, the most advanced "renewable" technologies are too often based upon non-renewable resources, attendees heard.

-High Efficiency Multi-Junction Solar Cells require iridium which is also used in LCD manufacturing. There is an estimated 10 year supply at current usage levels.

-Hydrogen Fuel Cells require platinum. 15 year supply.

-Bio-fuels have multiple problems, including exhaustion of arable lands.

Quite the dilemma huh? Well not really, either we find new sources or develop new technologies but the point is that the TANSTAAFL principle applies even to "sustainable" energy.

via Slashdot