Predicting the sustainability of a future hydrogen economy entails taking into account a variety of factors related to hydrogen production, storage, distribution, and utilization. As renewable energy sources such as wind and solar expand, they can be used to generate hydrogen fuel in a sustainable manner. However, implementing such a strategy on a large scale necessitates the dedication of land and water to this purpose.
A recent study published in Nature Communications by Carnegie’s Lorenzo Rosa and visiting scholar Davide Tonelli from ULB and UCLouvain examines the challenges of meeting various hydrogen demand scenarios on a country-by-country basis.
Electrolysis is a method of producing hydrogen in which water is split into oxygen gas and hydrogen gas, which can then be stored and used as fuel or feedstock to produce useful chemicals. This process can be powered by fossil fuels such as coal or natural gas, or by renewable energy sources such as wind and solar, both of which require space to be installed.
Our work indicates countries that have the resources to ramp up sustainable hydrogen production for export. But, of course, social, political, and economic factors will determine the extent of installation of renewable technologies and hydrogen production from each nation, which may differ from what would be feasible on paper.
Davide Tonelli
“Today, hydrogen is mostly used in refineries and the production of chemicals,” she said. “However, due to the adoption of hydrogen or hydrogen-derived products in transportation, industrial heating methods, and steel manufacturing techniques in the future, demand for hydrogen could more than fivefold.” There is an opportunity to meet this increased demand with hydrogen produced in a sustainable manner.”
He and Tonelli — working with Carnegie visiting scholar Paolo Gabrielli (of ETH Zurich), Carnegie’s Ken Calderia, Alessandro Parente of ULB, and Francesco Contino of UCLouvain – found that due to land or water scarcity, less than half of the projected 2050 demand for hydrogen fuel could be both produced and used locally using wind or solar power.
“If you look at how much water would be needed globally to produce enough hydrogen to meet humanity’s needs in 2050, it’s only 0.6 percent of the world’s available water,” Tonelli said. “But when you look at local production for local use, the picture can be different.”
It turns out that in a net-zero world with no carbon emissions, some countries would have to rely on importing hydrogen, either in pure form or as hydrogen-derived products, from other countries with more land and more favorable solar and wind resources that could be deployed to sustainably produce it in mass quantities.
Rosa and Tonelli discovered that land and water availability in Southern Africa, Central-East Africa, West Africa, South America, Canada, and Australia make them potential leaders in hydrogen export. Western Europe, Trinidad and Tobago, South Korea, and Japan, on the other hand, would almost certainly need to import hydrogen fuel or reduce existing industrial output.
The researchers stress the importance of conducting national assessments of the resources that countries are willing to invest in hydrogen production.
“Our work indicates countries that have the resources to ramp up sustainable hydrogen production for export,” Tonelli went on to say. “But, of course, social, political, and economic factors will determine the extent of installation of renewable technologies and hydrogen production from each nation, which may differ from what would be feasible on paper.”
This study is a component of Rosa’s larger program to investigate opportunities and challenges at the intersection of energy, water, and food production, all of which are impacted by climate change and population growth.
“As we strive to mitigate greenhouse gas pollution and prepare for the ways that climate change will affect where we live, how we build and sustain communities, and how we feed ourselves, it is crucial that we robustly examine various climate solutions to understand the possibilities that they present, as well as any unintended consequences,” Rosa said.
