Two primary aspects of energy sustainability:

Can the current energy consumption profile last?
The state of the current energy profile is heavily dependent on the fossil fuels. In the economic sense the as the fuel begins into higher demand and the production begins to drop the price will increase. As discussed in class the current trend of use of fossil fuel can continue for only 100 more years, this will cause a steep increase in cost for the worlds energy cost. The current profile is on a sharp increase over the last hundred years. This trend cannot continue for the factor of cost and depletion in time.

If the current energy profile of the world is sustained what impact will it have on the environment?
One can only speculate the possibilities of the environment of the future, although examining our recent history hypothesis can be taken. The environmental impact of the current energy profile is a very noticeable amount in the last hundred year and noticeable effects have taken place in the environment. Increases in greenhouse gases and pollution have been exponentially experienced. The temperature, on average, of the world has increased. Though the increase of the temperature has only changed slightly the continuing trend could dramatically change the world's climate enough to effect living conditions.