Long-term sustainability

It is clear that satisfying the projected needs of a constantly growing world population with the economy we now have is simply not possible.

The economic model in place in the West — a fossil-fuel-based, automobile-centred, disposable-goods economy — that so dramatically raised living standards for part of humanity during the past century is revealing its weaknesses. Indeed, the global economy cannot expand indefinitely if the ecosystems on which it depends continue to deteriorate.

If the Western model were to become the global model, and if the world's population were to reach 10 billion during the next century as the United Nations projects, the effects would be startling.

If, for example, the world had one car for every two people in 2050 — as in the United States today — there would be 5 billion cars. Considering the traffic congestion, pollution, fuel use, and land requirements of the current global fleet of 500 million cars, a fleet of 5 billion is difficult to imagine.

If petroleum use per person were to reach the current U.S. level, the world would consume 360 million barrels per day, compared with current production of 67 million barrels.

Following the American diet, ten billion people would require 9 billion tonnes of grain per year, the harvest of more than four planets at the Earth's current output levels.

An economy can be maintained in the long term only if it satisfies the principles of sustainability:

• The fish catch must not exceed the sustainable yield of fisheries.

• The amount of water pumped from underground aquifers must not exceed aquifer recharge.

• Soil erosion must not exceed the natural rate of new soil formation.

• Tree cutting must not exceed tree planting.

• Carbon emissions must not exceed the capacity of nature to process atmospheric carbon dioxide.

• Plant and animal species must not be eliminated faster than new ones evolve.

The foundation of the new economic model is a new design principle — one that shifts from one-time depletion of natural resources to one that is based on renewable energy and that continually reuses and recycles materials. It is a solar-powered, bicycle and rail centred, reuse/recycle economy model that uses energy, water, land, and materials much more efficiently and wisely than we do today.