Published on January 27th, 2011 | by Joshua S Hill
A New Vision for the Future
Every now and again really smart people make pushes in science that need to be taken note of. At the moment, if there is one area in the world where smart people need to invest their time, it is poverty and the environment.
Thankfully, Stanford researcher Mark Z. Jacobson and Mark Delucchi of the University of California, Davis, have co-authored a plan that would convert the entire planet to renewable energy sources and halt the use of and need for fossil fuels.
“Based on our findings, there are no technological or economic barriers to converting the entire world to clean, renewable energy sources,” said Jacobson, a professor of civil and environmental engineering. “It is a question of whether we have the societal and political will.”
Jacobson and Delucchi have written a two-part paper in the journal Energy Policy which assesses the cost, technology, and the material requirements of converting the planet to fossil-fuel-free and entirely renewable-energy-dependant; a plan they devised themselves.
The plan calls for 50 percent wind, 40 percent solar, with the remaining 10 percent made up of all the other renewable energies to fill in the gaps (geothermal and hydroelectric sources would each contribute about 4 percent in their plan, of which 70 percent of the hydroelectric is already in place, with the remaining 2 percent from wave and tidal power).
Vehicles, ships and trains would be powered by electricity and hydrogen fuel cells, and aircraft would run on liquid hydrogen. Homes would be cooled and warmed with electric heaters and water would be preheated by the sun, eliminating any need for natural gas or coal. Commercial processes would be powered by electricity and hydrogen.
In all cases, the hydrogen used for powering the processes mentioned above would be produced by electricity, once again bringing us back to wind, water and the sun powering the world.
Jacobson and Delucchi approached the conversion of our planet to their plan with the goal that by 2030 all new energy generation would come from wind, water and solar, and by 2050 all pre-existing energy production would be converted as wel.
“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,” said Jacobson.
The results of implementing the plan would be a 30 percent reduction in world energy demand, reducing the amount of lives taken by world pollution, currently estimated at being between 2.5 and 3 million people, and halting global warming in its tracks.
“When you actually account for all the costs to society – including medical costs – of the current fuel structure, the costs of our plan are relatively similar to what we have today,” Jacobson said.
One of the issues that critics of renewable energy throw at its proponents is that of variability, the fact that both wind and solar cannot necessarily be relied upon to provide 100 percent power generation 100 percent of the time.
Jacobson, unsurprisingly, believes that variability can be overcome.
“The most important thing is to combine renewable energy sources into a bundle,” he said. “If you combine them as one commodity and use hydroelectric to fill in gaps, it is a lot easier to match demand.”
Wind and solar are complementary, Jacobson said, as wind often peaks at night and sunlight peaks during the day. Using hydroelectric power to fill in the gaps, as it does in our current infrastructure, allows demand to be precisely met by supply in most cases. Other renewable sources such as geothermal and tidal power can also be used to supplement the power from wind and solar sources.
Something like this would surely cost more than is currently in place, but according to the researchers that is not true. Jacobson and Delucchi assessed whether their plan would run into problems with the amount of material they would need to implement their plan, and found that even materials such as platinum and rare earth metals are available in sufficient amounts, which could be extended through recycling.
“For solar cells there are different materials, but there are so many choices that if one becomes short, you can switch,” Jacobson said. “Major materials for wind energy are concrete and steel and there is no shortage of those.”
The number of wind turbines and sola plants, rooftop photovoltaic cells, geothermal, hydroelectric, tidal and wave-energy installations was also calculated. To power 100 percent of the world for all purposes from the renewable energies, the footprint needed is about 0.4 percent of the world’s land – which is made up mostly of solar – and the spacing between installations is another 0.6 percent of the world’s land – which is made up mostly of wind-turbine spacing.
Another kink that critics throw into the works is that of the amount of spacing needed between wind turbines, which in turn require large amounts of land set apart for wind farms. But Jacobson debunks this critique as well.
“Most of the land between wind turbines is available for other uses, such as pasture or farming,” Jacobson said. “The actual footprint required by wind turbines to power half the world’s energy is less than the area of Manhattan.” If half the wind farms were located offshore, a single Manhattan would suffice.
“This really involves a large scale transformation,” said 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.”