Solar energy for a circular economy


The SUNRISE project, in which UCLouvain participates, just received €1 million from the European Union. With this sum, for one year, the consortium will establish a road map and build a community around a sustainable alternative project to produce fuels and basic chemicals. Gian-Marco Rignanese, a UCLouvain part-time professor of materials science and the Belgian spokesperson for the SUNRISE project, explains.

There’s no longer any doubt: the climate is one of today’s greatest challenges. The latest IPCC report demands that we limit the rise in the earth's temperature to 2 degrees maximum in order to avoid the serious consequences of global warming. To do this, carbon dioxide emissions should be reduced by about 20% by 2030 and completely eliminated by the second half of the 21st century at the latest. In other words, by 2050, any use of fossil fuels should be offset by CO2 capture in the atmosphere. But how to spark this transition to a low-emission society? The European SUNRISE project, in which UCLouvain is one of 20 partners supported by more than 150 academic, industry and public sector actors, aims to meet the challenge.

Toward large-scale research

SUNRISE is one of the six European Union-led Coordination and Support Action Programmes (CSA) under the Horizon 2020 programme for establishing a large-scale European research initiative (such as Flagship). This collaborative project does not fund research or development but rather coordination and support for research activity and strategies. In February 2018, a first call was launched in three areas: health, automation and sustainable energy. Approximately 15 proposals were selected for a second round of review beginning in September 2018. Six, including SUNRISE, were selected in January 2019. Each received €1 million to:

  • define a scientific and technological road map;

  • mobilise stakeholders from various industrial, academic and societal sectors;

  • establish an effective management and decision-making structure.

In the spring of 2020, two of the projects will be chosen to receive €1 billion to make their research a reality.

An alternative to fossil fuels

Concretely, SUNRISE proposes to develop a sustainable alternative for the production of fuels and basic chemicals. Today, this production is very energy intensive and requires high consumption of fossil resources. Tomorrow, SUNRISE would like this energy to be provided by the sun and raw materials in the atmosphere such as carbon dioxide (CO2), oxygen (O2), and nitrogen (N2). In other words, SUNRISE wants to achieve a circular economy based on solar energy. By recycling carbon dioxide (CO2) from combustion as a raw material, we could produce solar fuels and chemicals. For example, CO2 produced via combustion could be captured, concentrated, and converted back into fuel using solar energy, instead of adding it to greenhouse gases in the atmosphere. The advantage of this alternative is that the use of energy resources is free, infinite and available everywhere thanks to the sun.

Artificial photosynthesis

How is all this possible? In the short term, the idea is to use already existing renewables (photovoltaic and wind) to produce energy that splits water into its components (electrochemical process of electrolysis), then produce hydrogen and other solar fuels at the industrial level. In the medium and long term, the goal is to directly convert solar energy through artificial photosynthesis. Plants convert solar energy, water and carbon dioxide into carbohydrates that fuel their cellular activities. Artificial photosynthesis works in the same way but with materials created by humans. It still remains to manufacture devices that combine solar energy recovery and conversion. In addition, a bio-hybrid, organic and non-organic approach would complete this new way of recycling energy.

Technological challenges to take up

This ambitious project obviously involves many challenges. The main one is new technologies: the objective is to develop technologies to reach 70% of the thermodynamic limit, by absorbing a maximum of light (90% of photons) and converting the energy with a yield of 80% in chemical products. The next challenge will be to expand these technologies on an industrial scale while keeping production costs from skyrocketing. Solar fuels must be competitive with fossil fuels. To achieve this, we will have to develop even more efficient materials to capture CO2 more optimally. Finally, the transition to a circular economy will have strong economic and social implications that will be evaluated during this year of discussion.

What prospects for 2030 and 2050?

Today, the scientific and technological road map is not yet established but some objectives are. Overall, SUNRISE aims to provide sustainable carbon from renewable energy, and to synthesise basic chemicals. To do so:

  • By 2030, the goal is to use the simplest molecules (CO2, H2O, N2 and O2) as raw materials in order to convert them through solar energy and produce solar fuels and basic chemicals. To enter the circular economy system, 2,500 tonnes of CO2 per hectare per year must be converted. By 2030, CO2 emissions would be neutralised.

  • By 2050, the goal is to further reduce CO2 emissions entering the atmosphere by implementing large-scale technological expansion and therefore greater efficiency. By 2050, CO2 emissions would be negative.

A vast network to build

From the spring of 2019, the SUNRISE team will expand to form a European network capable of carrying out the project. For the moment, at UCLouvain, Prof. Rignanese is bringing to bear his modelling skills in materials science. In particular, he will propose new materials that could improve the photocatalysis of water and contribute to the implementation of artificial photosynthesis. The consortium already has seven other universities, research and technology organisations, and industry corporations (Siemens, ENGIE, EMIRI, Johnson Matthey). Within the SUNRISE project, there are 150 industry, academic, NGO and public supporters. Together with new actors, they will agree on a roadmap for a circular economy by April 2020.

Lauranne Garitte

A glance at Gian-Marco Rignanese

Gian-Marco Rignanese is a physics engineer (1994) and doctor of applied sciences (1998) at UCLouvain. He worked as a consultant for CRAY RESEARCH at the Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland, then completed a postdoc at the University of California, Berkeley, USA, before obtaining a permanent position at F.R.S.-FNRS and UCLouvain (2003). He is currently a part-time professor at UCLouvain and an F.R.S.-FNRS research director.

His research focuses on simulations of the properties of materials based on first principles (quantum mechanics and electromagnetism). He participates in the development of ABINIT software ( distributed under GNU licence, which allows this type of simulation, and collaborates actively in the Materials Project (,which gathers high-speed computation data for tens of thousands of materials.

Published on April 04, 2019