139 countries could be powered by 100 percent wind, water, and solar energy by 2050
Cell Press says that the analyses specifically examined each country’s electricity, transportation, heating/cooling, industrial, and agriculture/forestry/fishing sectors. Of the 139 countries—selected because they were countries for which data were publically available from the International Energy Agency and collectively emit over 99 percent of all carbon dioxide worldwide—the places the study showed that had a greater share of land per population (for example, the United States, China, the European Union) are projected to have the easiest time making the transition to 100 percent wind, water, and solar. Another learning was that the most difficult places to transition may be highly populated, very small countries surrounded by lots of ocean, such as Singapore, which may require an investment in offshore solar to convert fully.
As a result of a transition, the roadmaps predict a number of collateral benefits. For example, by eliminating oil, gas, and uranium use, the energy associated with mining, transporting and refining these fuels is also eliminated, reducing international power demand by around 13 percent. Because electricity is more efficient than burning fossil fuels, demand should go down another 23 percent. The changes in infrastructure would also mean that countries wouldn’t need to depend on one another for fossil fuels, reducing the frequency of international conflict over energy. Finally, communities currently living in energy deserts would have access to abundant clean, renewable power.
“Aside from eliminating emissions and avoiding 1.5 degrees Celsius global warming and beginning the process of letting carbon dioxide drain from the Earth’s atmosphere, transitioning eliminates 4-7 million air pollution deaths each year and creates over twenty-four million long-term, full-time jobs by these plans,” Jacobson says. “What is different between this study and other studies that have proposed solutions is that we are trying to examine not only the climate benefits of reducing carbon but also the air pollution benefits, job benefits, and cost benefits”
The Joule paper is an expansion of 2015 roadmaps to transition each of the 50 United States to 100 percent clean, renewable energy (Energy & Environmental Science [27 May 2015]) and an analysis of whether the electric grid can stay stable upon such a transition (PNAS [2 November 2015]). Not only does this new study cover nearly the entire world, there are also improved calculations on the availability of rooftop solar energy, renewable energy resources, and jobs created versus lost.
The 100 percent clean, renewable energy goal has been criticized by some for focusing only on wind, water, and solar energy and excluding nuclear power, “clean coal,” and biofuels. However, the researchers intentionally exclude nuclear power because of its 10-19 years between planning and operation, its high cost, and the acknowledged meltdown, weapons proliferation, and waste risks. “Clean coal” and biofuels are neglected because they both cause heavy air pollution, which Jacobson and coworkers are trying to eliminate, and emit over fifty times more carbon per unit of energy than wind, water, or solar power.
The 100 percent wind, water, solar studies have also been questioned for depending on some technologies such as underground heat storage in rocks, which exists only in a few places, and the proposed use of electric and hydrogen fuel cell aircraft, which exist only in small planes at this time. Jacobson counters that underground heat storage is not required but certainly a viable option since it is similar to district heating, which provides 60 percent of Denmark’s heat. He also says that space shuttles and rockets have been propelled with hydrogen, and aircraft companies are now investing in electric airplanes. Wind, water, and solar can also face daily and seasonal fluctuation, making it possible that they could miss large demands for energy, but the new study refers to a new paper that suggests these stability concerns can be addressed in several ways.
These analyses have also been criticized for the massive investment it would take to move a country to the desired goal. Jacobson says that the overall cost to society (the energy, health, and climate cost) of the proposed system is one-fourth of that of the current fossil fuel system. In terms of upfront costs, most of these would be needed in any case to replace existing energy, and the rest is an investment that far more than pays itself off over time by nearly eliminating health and climate costs.
“It appears we can achieve the enormous social benefits of a zero-emission energy system at essentially no extra cost,” says co-author Mark Delucchi, a research scientist at the Institute of Transportation Studies, University of California, Berkeley. “Our findings suggest that the benefits are so great that we should accelerate the transition to wind, water, and solar, as fast as possible, by retiring fossil-fuel systems early wherever we can.”
“This paper helps push forward a conversation within and between the scientific, policy, and business communities about how to envision and plan for a decarbonized economy,” writes Mark Dyson of Rocky Mountain Institute, in an accompanying preview of the paper. “The scientific community’s growing body of work on global low-carbon energy transition pathways provides robust evidence that such a transition can be accomplished, and a growing understanding of the specific levers that need to be pulled to do so. Jacobson et al.’s present study provides sharper focus on one scenario, and refines a set of priorities for near-term action to enable it.”
— Read more in Mark Z. Jacobson et al., “100% Clean and Renewable Wind, Water, and Sunlight All-Sector Energy Roadmaps for 139 Countries of the World,” Joule (23 August 2017); Mark Z. Jacobson et al., “100% clean and renewable wind, water, and sunlight (WWS) all-sector energy roadmaps for the 50 United States,” Energy & Environmental Science (27 May 2015) (doi: 10.1039/C5EE01283J); and Mark Z. Jacobson et al., “Low-cost solution to the grid reliability problem with 100% penetration of intermittent wind, water, and solar for all purposes,” PNAS (2 November 2015) (doi:10.1073/pnas.1510028112)
