In an article in the November issue of Scientific American, Stanford professor Mark Jacobson (who we’ve written about before on the blog) released a plan where 100% of the world’s energy consumption comes from renewable sources by the year 2030. This is obviously an ambitious plan, but Jacobson (and his coauthor, Mark Delucchi), say it is achievable with worldwide governmental support.

In the plan, 51% of energy generation across the globe would come from wind energy. That amount of generation would require building 3.8 million 5 MW wind turbines. While that seems like an outrageous number, Jacobson mentions that 73 million cars and light trucks are manufactured every year. The remaining 49% of generation would come from solar and hydro .

In Jacobson’s vision, renewable sources will provide electric power for heating and transportation. While this will require large changes in infrastructure–and the mass adoption of electric vehicles–it will actually save on energy use over time, as electric power runs more efficiently than traditional fossil fuels. (For example, in a vehicle with an internal combustion engine, 80% of the energy in gasoline is wasted as heat. In an electric vehicle, only about 20% of energy is wasted.)

A major limiting factor in the plan is cost–the paper estimates that the massive undertaking could cost $100 trillion. Aside from cost, shortages of necessary materials and lack of political will are seen as the primary stumbling blocks.

The writers acknowledge at the end of the paper that their vision is something of a pipe dream–more of a concept of what is possible than what is feasible.

With sensible policies, nations could set a goal of generating 25 percent of their new energy supply with WWS [wind, water, solar] sources in 10 to 15 years and almost 100 percent of new supply in 20 to 30 years. With extremely aggressive policies, all existing fossil-fuel capacity could theoretically be retired and replaced in the same period, but with more modest and likely policies full replacement may take 40 to 50 years. Either way, clear leadership is needed, or else nations will keep trying technologies promoted by industries rather than vetted by scientists.

Let’s hope legislators the world over are listening.