Is it possible for the fossil-fueled world we live in to switch to 100 percent renewable energy by 2030? Two U.S. researchers think it is possible. Mark Delucchi of the Institute for Transportation Studies at the University of California Davis, and Mark Jacobson of the civil and environmental engineering department at Stanford University did a study on what it would take to use 100 percent renewable energy. The results were published in the journal Energy Policy.
The researchers call for a wind, water and solar (WWS) system, with geothermal accounting for about six percent, and hydroelectric dams about four percent. Biomass is not considered. At present, all renewables provide 13 percent of the world energy supply, with biomass making up 10 percent.
Switching to renewable energy by 2030 would require four million wind turbines rated at five megawatts (MW), two to three times the capacity of most of the current ones on the market, according to the researchers. Switching to renewables would require 90,000 large-scale solar plants with a capacity of 300 MW, both photovoltaic (PV) panels and concentrated solar. Less than three dozen large-scale solar plants are operating globally. In addition to large-scale solar plants, 1.7 billion three kilowatt (KW) solar PV rooftop systems would be required, equaling one rooftop PV system for every four people in the world.
It would take a significant amount of steel and concrete to switch to renewables. The researchers concluded that it would be not be an economic or environmental problem to produce bulk amounts of concrete and steel. However, the production of rare earth metals such as neodymium could present a problem. Global production of neodymium would have to more than quintuple to build millions of wind turbines, but there should be enough because the current world reserves of it are about six times greater than what is needed. Rare earth metals could be recycled. Such a recycling program is not available currently.
“Technically you can do it,” Jacobson says. “It really depends on will power.”
“The real challenge is matching supply with demand,” Jacobson adds. “Wind and solar are very complementary…When the wind isn’t blowing, you usually have a clear, sunny day. And vice versa—when there’s less sunlight on a cloudy day, it’s usually windy.”