A study coauthored by Stanford researcher Mark Z. Jacobson states that the world could be powered by today’s existing alternative energy solutions within the next 20 to 40 years, with societal and political support.
Jacobson and Mark Delucchi, University of California-Davis, have written a document in Energy Policy determining the costs, technology, and material requirements of converting the planet to run on an alternative energy system.
This vision consists of a world running largely on electricity, utilizing wind, solar, and water energy to generate power. Wind and solar solutions would provide 90% of the energy.
"We wanted to quantify what is necessary in order to replace all the current energy infrastructure – for all purposes – with a really clean and sustainable energy infrastructure within 20 to 40 years," says Jacobson.
Since electricity is much more efficient than combustion, a 30% reduction in world energy demand overall would occur with the conversion of combustion processes to electrical or hydrogen fuel cell processes.
The biggest challenge to overcome in this switch to alternative energy is the variability factor – wind and solar energy can be highly variable, which has raised doubts about the reliability of the energy sources.
But Jacobson says that the variance can be overcome, as wind and solar power are complementary. Geothermal and tidal power could be used to supplement the wind and solar sources.
This project to transform the earth to an alternative energy plan is no small endeavor.
"This really involves a large scale transformation," says Jacobson. "It would require an effort comparable to the Apollo moon project or constructing the interstate highway system. But it is possible, without even having to go to new technologies; we really need to just decide collectively that this is the direction we want to head as a society."