Solar Fuels
Every year, fossil fuel consumption reaches record levels, threatening the climate, health and biodiversity due to air, water and soil pollution. Economic and geopolitical risks are also induced by this consumption. Transitioning to a post-fossil fuel era requires reducing energy consumption, adopting renewable energy sources for all energy services, and moving away from petrochemicals. However, due to a lack of viable alternatives, some industries continue to rely heavily on fossil fuels.
This project, supported by the Agora program of the Swiss National Science Foundation, explores solar fuels and materials, a promising alternative in areas where electrification falls short. It highlights innovations from the LRESE laboratory at EPFL, where these fuels and materials are synthesized directly from sunlight. In parallel, ZHdK's Industrial Design program presents speculative scenarios that investigate new relationships and interactions with resources and energy, imagining how design can shape our engagement with emerging energy technologies.
Summary
Ⅰ
Towards the transition to solar fuels and materials
Ⅱ
Container transition
Why do we use
Global demand im 2023
8687 Mt, 2.5% annual growth
Formation
Hundreds of millions years
Coal is formed from the decomposition of terrestrial vegetation, such as trees and plants, in swampy environments. The vegetation is progressively transformed into peat, into lignite, then into bituminous coal, and finally into anthracite under the efect of pressure and heat.
Peat
Approx. 60% carbon
Lignite
Approx. 70% carbon
Bituminous coal
Approx. 80% carbon
Anthracite
Approx. 90% carbone
Worldwide coal consumption
Source: Energy Institute - Statistical Review of World Energy (2024); Smil (2017) - with major processing by Our World in Data
Coal
Energy
Materials
Antiquity
Both in ancient Rome and China (from the fourth century onwards), coal was used for heating.
Both in ancient Rome and China (from the fourth century onwards), coal was used for heating.
Antiquity
The Romans used fossil coal in certain transformation processes, particularly for producing lime.
The Romans used fossil coal in certain transformation processes, particularly for producing lime.
Middle Ages
Fossil coal was mined for artisanal uses, particularly in metallurgy, locally whre it replaced carcoal.
Fossil coal was mined for artisanal uses, particularly in metallurgy, locally whre it replaced carcoal.
1712
Thomas Newcomen
First piston steam engine for pumping water from coal mines.
Thomas Newcomen
First piston steam engine for pumping water from coal mines.
1769
James Watt
Major improvement of steam engines. More powerful and economical, they were used in textile industry and metallurgy
James Watt
Major improvement of steam engines. More powerful and economical, they were used in textile industry and metallurgy
1800 (circa)
Coke
Produced from bituminous coal in oxygen-free furnaces, it facilitated the production of iron and steel, essential for machinery and infrastructure.
Coke
Produced from bituminous coal in oxygen-free furnaces, it facilitated the production of iron and steel, essential for machinery and infrastructure.
1802
William Symington
Charlotte Dundas, the first steamboat using fossil fuel.
William Symington
Charlotte Dundas, the first steamboat using fossil fuel.
1804
Richard Trevithick
Penydarren, the first functionnal steam locomotive, transported iron on a railway in Wales.
Richard Trevithick
Penydarren, the first functionnal steam locomotive, transported iron on a railway in Wales.
1882
Thomas Edison
La Pearl Street Station, première station éléctrique, aliment l'éclairage électrique des bureaux du New York Times et d'autres bâtiments autour de Wall Street.
Thomas Edison
La Pearl Street Station, première station éléctrique, aliment l'éclairage électrique des bureaux du New York Times et d'autres bâtiments autour de Wall Street.
Energy
Coal for households and services
Coal-fired power plant
Energy source for heavy industriy (e.g. cement, steelmaking)
Materials
Steel
Gas
Energy
Materials
Antiquity
The inhabitants of present-day China used natural gas, called “well fire”, transported in bamboo pipes, to produce salt through seawater evaporation.
The inhabitants of present-day China used natural gas, called “well fire”, transported in bamboo pipes, to produce salt through seawater evaporation.
1800 (circa)
Philippe Lebon & William Murdoch
Production of gas through coal pyrolysis: this method was used for industrial, public, and eventually private lighting.
Philippe Lebon & William Murdoch
Production of gas through coal pyrolysis: this method was used for industrial, public, and eventually private lighting.
1821
William Hart
First large-scale use of natural gas in New York to light the city and some offices following the (re)discovery of a natural gas well.
William Hart
First large-scale use of natural gas in New York to light the city and some offices following the (re)discovery of a natural gas well.
1960 (circa)
Natural gas displaced coal-derived gas as it has a calorific value twice as large and its combustion results in fewer particls, tar and sulfur compouds.
Natural gas displaced coal-derived gas as it has a calorific value twice as large and its combustion results in fewer particls, tar and sulfur compouds.
1964
First commercialization of liquefied natural gas, accelerating consumption growth; previously, it was very difficult to transport.
First commercialization of liquefied natural gas, accelerating consumption growth; previously, it was very difficult to transport.
Energy
Gas for household and services
Gas-fired power plant
Energy source for industry (e.g. glass, ceramics)
Oil for household and services
Oil-fired power plant
Fuel (e.g. gasoline, diesel, kerosene)
Materials
Construction materials
Plastics and synthetic fibers
Speciality chemicals and pharmaceuticals
Agrochemicals
Oil
Energy
Materials
Antiquity
Mesopotamians used oil obtained from natural seeps or by drilling as fuel for lighting. In China and Japan, “burning water” was used for lighting and heating.
Mesopotamians used oil obtained from natural seeps or by drilling as fuel for lighting. In China and Japan, “burning water” was used for lighting and heating.
Antiquity
The Mesopotamians and Native Americans used bitumen for caulking and its medicinal properties. The Egyptians used it for mummification and construction.
The Mesopotamians and Native Americans used bitumen for caulking and its medicinal properties. The Egyptians used it for mummification and construction.
900 (circa)
Al-Razi described the distillation process to produce lamp oil, which was used by the Byzantines and Venetians, particularly in Greeg fire”, to set enemy ships ablaze.
Al-Razi described the distillation process to produce lamp oil, which was used by the Byzantines and Venetians, particularly in Greeg fire”, to set enemy ships ablaze.
1855
George Bissell & Jonathan Eveleth
Pennsylvania petroleum, distilled to produce lamp oil, gradually replaced whale oil for lighting.
George Bissell & Jonathan Eveleth
Pennsylvania petroleum, distilled to produce lamp oil, gradually replaced whale oil for lighting.
1855
Benjamin Silliman
The distillation of petroleum yields various products, including tar, lubricants, naphtha, paint solvents, and gasoline, which was used as a stain remover.
Benjamin Silliman
The distillation of petroleum yields various products, including tar, lubricants, naphtha, paint solvents, and gasoline, which was used as a stain remover.
1859
Edwin Drake
Production of the first barrels of American petroleum in Titusville, Pennsylvania, United States.
Edwin Drake
Production of the first barrels of American petroleum in Titusville, Pennsylvania, United States.
1907
Leo Baekeland
Bakelite, the first fossil-derived plastic, is made from phenol combined with formaldehyde (synthesized from methanol, which comes from natural gas or coal).
Leo Baekeland
Bakelite, the first fossil-derived plastic, is made from phenol combined with formaldehyde (synthesized from methanol, which comes from natural gas or coal).
1886
Karl Benz
The first modern automobile: a tricycle equipped with an internal combustion engine running on gasoline, capable of reaching 16 km/h.
Karl Benz
The first modern automobile: a tricycle equipped with an internal combustion engine running on gasoline, capable of reaching 16 km/h.
1905
Henry Ford
Mass production of the Ford Model T, creating a large market for liquid fuels through the automobile industry. Petroleum became essential in the twentieth century.
Henry Ford
Mass production of the Ford Model T, creating a large market for liquid fuels through the automobile industry. Petroleum became essential in the twentieth century.
1925
Fischer-Tropsch
Discovery of SynFuel, a liquid fuel made from hydrogen and carbon monoxide. It was widely used by Nazi Germany, which, being isolated, produced it from coal.
Fischer-Tropsch
Discovery of SynFuel, a liquid fuel made from hydrogen and carbon monoxide. It was widely used by Nazi Germany, which, being isolated, produced it from coal.
1925 (circa)
Steam cracking produced the derivatives required to manufacture plastics and specialized products from natural gas or petroleum; the residues were used for asphalt.
Steam cracking produced the derivatives required to manufacture plastics and specialized products from natural gas or petroleum; the residues were used for asphalt.
Energy
Oil for household and services
Oil-fired power plant
Fuel (e.g. gasoline, diesel, kerosene)
Materials
Construction materials
Plastics and synthetic fibers
Speciality chemicals and pharmaceuticals
Agrochemicals
Global demand in 2023
4010.2 billions of cubic meters, 0.02% annual growth
Formation
Ranging from several tens to hundreds of millions years
Natural gas is formed primarily from the decomposition of organic matter under the effect of heat and pressure (thermogenesis) or the action of microorganism (biogenesis). Once formed, natural gas migrates through layers of porous rocks until it is trapped beneath impermeable formations.
CH4
Methane
70%–90% natural gas.
C2H6
Ethane
10% natural gas
C3H8
Propane
Small quantities of natural gas
C4H10
Butane
Small quantities of natural gas
Worldwide gas consumption
Source: Energy Institute - Statistical Review of World Energy (2024); Smil (2017) - with major processing by Our World in Data
Coal
Energy
Materials
Antiquity
Both in ancient Rome and China (from the fourth century onwards), coal was used for heating.
Both in ancient Rome and China (from the fourth century onwards), coal was used for heating.
Antiquity
The Romans used fossil coal in certain transformation processes, particularly for producing lime.
The Romans used fossil coal in certain transformation processes, particularly for producing lime.
Middle Ages
Fossil coal was mined for artisanal uses, particularly in metallurgy, locally whre it replaced carcoal.
Fossil coal was mined for artisanal uses, particularly in metallurgy, locally whre it replaced carcoal.
1712
Thomas Newcomen
First piston steam engine for pumping water from coal mines.
Thomas Newcomen
First piston steam engine for pumping water from coal mines.
1769
James Watt
Major improvement of steam engines. More powerful and economical, they were used in textile industry and metallurgy
James Watt
Major improvement of steam engines. More powerful and economical, they were used in textile industry and metallurgy
1800 (circa)
Coke
Produced from bituminous coal in oxygen-free furnaces, it facilitated the production of iron and steel, essential for machinery and infrastructure.
Coke
Produced from bituminous coal in oxygen-free furnaces, it facilitated the production of iron and steel, essential for machinery and infrastructure.
1802
William Symington
Charlotte Dundas, the first steamboat using fossil fuel.
William Symington
Charlotte Dundas, the first steamboat using fossil fuel.
1804
Richard Trevithick
Penydarren, the first functionnal steam locomotive, transported iron on a railway in Wales.
Richard Trevithick
Penydarren, the first functionnal steam locomotive, transported iron on a railway in Wales.
1882
Thomas Edison
La Pearl Street Station, première station éléctrique, aliment l'éclairage électrique des bureaux du New York Times et d'autres bâtiments autour de Wall Street.
Thomas Edison
La Pearl Street Station, première station éléctrique, aliment l'éclairage électrique des bureaux du New York Times et d'autres bâtiments autour de Wall Street.
Energy
Coal for households and services
Coal-fired power plant
Energy source for heavy industriy (e.g. cement, steelmaking)
Materials
Steel
Gas
Energy
Materials
Antiquity
The inhabitants of present-day China used natural gas, called “well fire”, transported in bamboo pipes, to produce salt through seawater evaporation.
The inhabitants of present-day China used natural gas, called “well fire”, transported in bamboo pipes, to produce salt through seawater evaporation.
1800 (circa)
Philippe Lebon & William Murdoch
Production of gas through coal pyrolysis: this method was used for industrial, public, and eventually private lighting.
Philippe Lebon & William Murdoch
Production of gas through coal pyrolysis: this method was used for industrial, public, and eventually private lighting.
1821
William Hart
First large-scale use of natural gas in New York to light the city and some offices following the (re)discovery of a natural gas well.
William Hart
First large-scale use of natural gas in New York to light the city and some offices following the (re)discovery of a natural gas well.
1960 (circa)
Natural gas displaced coal-derived gas as it has a calorific value twice as large and its combustion results in fewer particls, tar and sulfur compouds.
Natural gas displaced coal-derived gas as it has a calorific value twice as large and its combustion results in fewer particls, tar and sulfur compouds.
1964
First commercialization of liquefied natural gas, accelerating consumption growth; previously, it was very difficult to transport.
First commercialization of liquefied natural gas, accelerating consumption growth; previously, it was very difficult to transport.
Energy
Gas for household and services
Gas-fired power plant
Energy source for industry (e.g. glass, ceramics)
Oil for household and services
Oil-fired power plant
Fuel (e.g. gasoline, diesel, kerosene)
Materials
Construction materials
Plastics and synthetic fibers
Speciality chemicals and pharmaceuticals
Agrochemicals
Oil
Energy
Materials
Antiquity
Mesopotamians used oil obtained from natural seeps or by drilling as fuel for lighting. In China and Japan, “burning water” was used for lighting and heating.
Mesopotamians used oil obtained from natural seeps or by drilling as fuel for lighting. In China and Japan, “burning water” was used for lighting and heating.
Antiquity
The Mesopotamians and Native Americans used bitumen for caulking and its medicinal properties. The Egyptians used it for mummification and construction.
The Mesopotamians and Native Americans used bitumen for caulking and its medicinal properties. The Egyptians used it for mummification and construction.
900 (circa)
Al-Razi described the distillation process to produce lamp oil, which was used by the Byzantines and Venetians, particularly in Greeg fire”, to set enemy ships ablaze.
Al-Razi described the distillation process to produce lamp oil, which was used by the Byzantines and Venetians, particularly in Greeg fire”, to set enemy ships ablaze.
1855
George Bissell & Jonathan Eveleth
Pennsylvania petroleum, distilled to produce lamp oil, gradually replaced whale oil for lighting.
George Bissell & Jonathan Eveleth
Pennsylvania petroleum, distilled to produce lamp oil, gradually replaced whale oil for lighting.
1855
Benjamin Silliman
The distillation of petroleum yields various products, including tar, lubricants, naphtha, paint solvents, and gasoline, which was used as a stain remover.
Benjamin Silliman
The distillation of petroleum yields various products, including tar, lubricants, naphtha, paint solvents, and gasoline, which was used as a stain remover.
1859
Edwin Drake
Production of the first barrels of American petroleum in Titusville, Pennsylvania, United States.
Edwin Drake
Production of the first barrels of American petroleum in Titusville, Pennsylvania, United States.
1907
Leo Baekeland
Bakelite, the first fossil-derived plastic, is made from phenol combined with formaldehyde (synthesized from methanol, which comes from natural gas or coal).
Leo Baekeland
Bakelite, the first fossil-derived plastic, is made from phenol combined with formaldehyde (synthesized from methanol, which comes from natural gas or coal).
1886
Karl Benz
The first modern automobile: a tricycle equipped with an internal combustion engine running on gasoline, capable of reaching 16 km/h.
Karl Benz
The first modern automobile: a tricycle equipped with an internal combustion engine running on gasoline, capable of reaching 16 km/h.
1905
Henry Ford
Mass production of the Ford Model T, creating a large market for liquid fuels through the automobile industry. Petroleum became essential in the twentieth century.
Henry Ford
Mass production of the Ford Model T, creating a large market for liquid fuels through the automobile industry. Petroleum became essential in the twentieth century.
1925
Fischer-Tropsch
Discovery of SynFuel, a liquid fuel made from hydrogen and carbon monoxide. It was widely used by Nazi Germany, which, being isolated, produced it from coal.
Fischer-Tropsch
Discovery of SynFuel, a liquid fuel made from hydrogen and carbon monoxide. It was widely used by Nazi Germany, which, being isolated, produced it from coal.
1925 (circa)
Steam cracking produced the derivatives required to manufacture plastics and specialized products from natural gas or petroleum; the residues were used for asphalt.
Steam cracking produced the derivatives required to manufacture plastics and specialized products from natural gas or petroleum; the residues were used for asphalt.
Energy
Oil for household and services
Oil-fired power plant
Fuel (e.g. gasoline, diesel, kerosene)
Materials
Construction materials
Plastics and synthetic fibers
Speciality chemicals and pharmaceuticals
Agrochemicals
Global demand in 2023
102.21 millions of barels per day, 2.65% annual growth
Formation
Ranging from several tens to hundreds of millions years
Oil is formed from the decomposition of marine organic matter, primarily plankton and algae, in environments devoid of oxygen.
CnH2n+2
Alkanes (paraffin)
CnH2n
Cycloalkane (naphthene)
Aromatics, among others:
C6H6
Benzene
C6H5CH3
Toluene
(CH3)2C6H3
Xylene
Benzene
C6H5CH3
Toluene
(CH3)2C6H3
Xylene
Worldwide oil consumption
Source: Energy Institute - Statistical Review of World Energy (2024); Smil (2017) - with major processing by Our World in Data
Coal
Energy
Materials
Antiquity
Both in ancient Rome and China (from the fourth century onwards), coal was used for heating.
Both in ancient Rome and China (from the fourth century onwards), coal was used for heating.
Antiquity
The Romans used fossil coal in certain transformation processes, particularly for producing lime.
The Romans used fossil coal in certain transformation processes, particularly for producing lime.
Middle Ages
Fossil coal was mined for artisanal uses, particularly in metallurgy, locally whre it replaced carcoal.
Fossil coal was mined for artisanal uses, particularly in metallurgy, locally whre it replaced carcoal.
1712
Thomas Newcomen
First piston steam engine for pumping water from coal mines.
Thomas Newcomen
First piston steam engine for pumping water from coal mines.
1769
James Watt
Major improvement of steam engines. More powerful and economical, they were used in textile industry and metallurgy
James Watt
Major improvement of steam engines. More powerful and economical, they were used in textile industry and metallurgy
1800 (circa)
Coke
Produced from bituminous coal in oxygen-free furnaces, it facilitated the production of iron and steel, essential for machinery and infrastructure.
Coke
Produced from bituminous coal in oxygen-free furnaces, it facilitated the production of iron and steel, essential for machinery and infrastructure.
1802
William Symington
Charlotte Dundas, the first steamboat using fossil fuel.
William Symington
Charlotte Dundas, the first steamboat using fossil fuel.
1804
Richard Trevithick
Penydarren, the first functionnal steam locomotive, transported iron on a railway in Wales.
Richard Trevithick
Penydarren, the first functionnal steam locomotive, transported iron on a railway in Wales.
1882
Thomas Edison
La Pearl Street Station, première station éléctrique, aliment l'éclairage électrique des bureaux du New York Times et d'autres bâtiments autour de Wall Street.
Thomas Edison
La Pearl Street Station, première station éléctrique, aliment l'éclairage électrique des bureaux du New York Times et d'autres bâtiments autour de Wall Street.
Energy
Coal for households and services
Coal-fired power plant
Energy source for heavy industriy (e.g. cement, steelmaking)
Materials
Steel
Gas
Energy
Materials
Antiquity
The inhabitants of present-day China used natural gas, called “well fire”, transported in bamboo pipes, to produce salt through seawater evaporation.
The inhabitants of present-day China used natural gas, called “well fire”, transported in bamboo pipes, to produce salt through seawater evaporation.
1800 (circa)
Philippe Lebon & William Murdoch
Production of gas through coal pyrolysis: this method was used for industrial, public, and eventually private lighting.
Philippe Lebon & William Murdoch
Production of gas through coal pyrolysis: this method was used for industrial, public, and eventually private lighting.
1821
William Hart
First large-scale use of natural gas in New York to light the city and some offices following the (re)discovery of a natural gas well.
William Hart
First large-scale use of natural gas in New York to light the city and some offices following the (re)discovery of a natural gas well.
1960 (circa)
Natural gas displaced coal-derived gas as it has a calorific value twice as large and its combustion results in fewer particls, tar and sulfur compouds.
Natural gas displaced coal-derived gas as it has a calorific value twice as large and its combustion results in fewer particls, tar and sulfur compouds.
1964
First commercialization of liquefied natural gas, accelerating consumption growth; previously, it was very difficult to transport.
First commercialization of liquefied natural gas, accelerating consumption growth; previously, it was very difficult to transport.
Energy
Gas for household and services
Gas-fired power plant
Energy source for industry (e.g. glass, ceramics)
Oil for household and services
Oil-fired power plant
Fuel (e.g. gasoline, diesel, kerosene)
Materials
Construction materials
Plastics and synthetic fibers
Speciality chemicals and pharmaceuticals
Agrochemicals
Oil
Energy
Materials
Antiquity
Mesopotamians used oil obtained from natural seeps or by drilling as fuel for lighting. In China and Japan, “burning water” was used for lighting and heating.
Mesopotamians used oil obtained from natural seeps or by drilling as fuel for lighting. In China and Japan, “burning water” was used for lighting and heating.
Antiquity
The Mesopotamians and Native Americans used bitumen for caulking and its medicinal properties. The Egyptians used it for mummification and construction.
The Mesopotamians and Native Americans used bitumen for caulking and its medicinal properties. The Egyptians used it for mummification and construction.
900 (circa)
Al-Razi described the distillation process to produce lamp oil, which was used by the Byzantines and Venetians, particularly in Greeg fire”, to set enemy ships ablaze.
Al-Razi described the distillation process to produce lamp oil, which was used by the Byzantines and Venetians, particularly in Greeg fire”, to set enemy ships ablaze.
1855
George Bissell & Jonathan Eveleth
Pennsylvania petroleum, distilled to produce lamp oil, gradually replaced whale oil for lighting.
George Bissell & Jonathan Eveleth
Pennsylvania petroleum, distilled to produce lamp oil, gradually replaced whale oil for lighting.
1855
Benjamin Silliman
The distillation of petroleum yields various products, including tar, lubricants, naphtha, paint solvents, and gasoline, which was used as a stain remover.
Benjamin Silliman
The distillation of petroleum yields various products, including tar, lubricants, naphtha, paint solvents, and gasoline, which was used as a stain remover.
1859
Edwin Drake
Production of the first barrels of American petroleum in Titusville, Pennsylvania, United States.
Edwin Drake
Production of the first barrels of American petroleum in Titusville, Pennsylvania, United States.
1907
Leo Baekeland
Bakelite, the first fossil-derived plastic, is made from phenol combined with formaldehyde (synthesized from methanol, which comes from natural gas or coal).
Leo Baekeland
Bakelite, the first fossil-derived plastic, is made from phenol combined with formaldehyde (synthesized from methanol, which comes from natural gas or coal).
1886
Karl Benz
The first modern automobile: a tricycle equipped with an internal combustion engine running on gasoline, capable of reaching 16 km/h.
Karl Benz
The first modern automobile: a tricycle equipped with an internal combustion engine running on gasoline, capable of reaching 16 km/h.
1905
Henry Ford
Mass production of the Ford Model T, creating a large market for liquid fuels through the automobile industry. Petroleum became essential in the twentieth century.
Henry Ford
Mass production of the Ford Model T, creating a large market for liquid fuels through the automobile industry. Petroleum became essential in the twentieth century.
1925
Fischer-Tropsch
Discovery of SynFuel, a liquid fuel made from hydrogen and carbon monoxide. It was widely used by Nazi Germany, which, being isolated, produced it from coal.
Fischer-Tropsch
Discovery of SynFuel, a liquid fuel made from hydrogen and carbon monoxide. It was widely used by Nazi Germany, which, being isolated, produced it from coal.
1925 (circa)
Steam cracking produced the derivatives required to manufacture plastics and specialized products from natural gas or petroleum; the residues were used for asphalt.
Steam cracking produced the derivatives required to manufacture plastics and specialized products from natural gas or petroleum; the residues were used for asphalt.
Energy
Oil for household and services
Oil-fired power plant
Fuel (e.g. gasoline, diesel, kerosene)
Materials
Construction materials
Plastics and synthetic fibers
Speciality chemicals and pharmaceuticals
Agrochemicals
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How can we do it?
The post-fossil transition requires reducing our energy consumption and electrifying our uses with renewables. Yet, sectors such as aviation, steelmaking, and cement production still depend on high-energy-density fuels due to a lack of truly sustainable alternatives. Likewise, petrochemistry and agrochemistry continue to rely on fossil resources as raw materials. Facing these challenges, solar fuels and materials are emerging as a promising solution, especially where electrification remains difficult.
Industry
Heavy
Renewable heat
Carbon capture and sequestration
Renewable electricity
Difficult to electrify (high temperature heat)
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Industry
Small
Renewable heat
Carbon capture and sequestration
Renewable electricity
Industry
Heavy
Renewable heat
Carbon capture and sequestration
Renewable electricity
Difficult to electrify (high temperature heat)
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Industry
Small
Renewable heat
Carbon capture and sequestration
Renewable electricity
Transportation
Trains
Green electricity with carbon-intensive infrastructure
Industry
Small
Renewable heat
Carbon capture and sequestration
Renewable electricity
Transportation
Trains
Green electricity with carbon-intensive infrastructure
Transportation
Cars
Buses
Boats
Trucks
Short distances
Long distances
Electric vehicles
Electrification is difficult
Green electricity with carbon-intensive infrastructure
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Transportation
Trains
Green electricity with carbon-intensive infrastructure
Transportation
Cars
Buses
Boats
Trucks
Short distances
Long distances
Electric vehicles
Electrification is difficult
Green electricity with carbon-intensive infrastructure
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Transportation
Planes
Agricultural machinery
Electrification is difficult
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Transportation
Cars
Buses
Boats
Trucks
Short distances
Long distances
Electric vehicles
Electrification is difficult
Green electricity with carbon-intensive infrastructure
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Transportation
Planes
Agricultural machinery
Electrification is difficult
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Residential and services
Solar collectors
Green electricity
Heat pump
Transportation
Planes
Agricultural machinery
Electrification is difficult
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Green synfuels
Green e-fuels
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Direct Solar Fuels
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Residential and services
Solar collectors
Green electricity
Heat pump
Steel
Experimental alternatives
(e.g. electric furnaces, biomass instead of coke, hydrogen as a reducing agent) but still not widely implemented
(e.g. electric furnaces, biomass instead of coke, hydrogen as a reducing agent) but still not widely implemented
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Recycling
Construction materials
Plastic and synthetic fibers
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Recycling
Green synthetic materials
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Thermochemical process
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
Green synthetic materials
Direct solar materials
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Steel
Experimental alternatives
(e.g. electric furnaces, biomass instead of coke, hydrogen as a reducing agent) but still not widely implemented
(e.g. electric furnaces, biomass instead of coke, hydrogen as a reducing agent) but still not widely implemented
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Recycling
Construction materials
Plastic and synthetic fibers
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Recycling
Green synthetic materials
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Thermochemical process
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
Green synthetic materials
Direct solar materials
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Speciality chemicals and pharmaceuticals
Agrochemicals
Green synthetic materials
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Thermochemical process
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
Green synthetic materials
Direct solar materials
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Construction materials
Plastic and synthetic fibers
Biomass-derived fuels
Significant competition with agricultural land and production complex porcesses
Significant competition with agricultural land and production complex porcesses
Recycling
Green synthetic materials
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Thermochemical process
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
Green synthetic materials
Direct solar materials
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
Speciality chemicals and pharmaceuticals
Agrochemicals
Green synthetic materials
Electrolysis from renewable energy
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Water is split into hydrogen and oxygen. Electrolysis of CO2 is also possible, but still at the research stage.
Green hydrogen
Thermochemical process
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
E.g. methanol synthesis, Haber-Bosch. Addition of N2 or CO2.
Green synthetic materials
Direct solar materials
Photoelectrochemistry
Thermochemistry
Unconcentrated light
Concentrated light
Solar Fuels
a brief history of solar reflectors
Yang Sui
Yang Sui is the name of a concave mirror, also called Jin Shu because it was made of bronze. Confucius, in his description of life in China three thousand years ago, mentions that every son attached a bronze burning mirror to his belt to light the family fire at the end of a sunny day. The Yang Sui, measuring about eight centimeters in diameter, was as common then as matches are today.
Archimedes
Legend has it that Archimedes used burning mirrors to set the Roman fleet on fire during the siege of Syracuse in 213-212 BCE. Historical evidence is far from conclusive. Modern experiments suggest that, under ideal conditions, the wood of these ships could have started to burn.
Augustin Mouchot
French inventor and pioneer in the field of solar energy, he notably designed a parabolic solar concentrator to heat water and produce steam. He used this steam to power a pump, thus demonstrating the mechanical application of solar energy. One of his solar concentrators was presented at the 1878 World’s Fair in Paris: It produced ice.
Maria Telkes
Maria Telkes, Hungarian and American inventor and solar energy pioneer, who later came to be known as the “Sun Queen,” invented a solar oven in 1959. The oven was designed for rural or less developed communities, to prepare any type of cuisine, and safe enough to be used by children. During the process of inventing this oven, she also developed a faster way for farmers to dry their crops.
How to manufacture solar fuels and materials?
Solar thermochemistry and photoelectrochemistry are two non-biological approaches for directly converting solar energy into fuels and materials. Solar thermochemistry uses concentrated sunlight to drive high-temperature chemical reactions. Photoelectrochemistry harnesses the photon energy by light-absorbing semiconductors and electrochemical interfaces and can work with or without concentrated sunlight.
Solar Thermochemistry
Water and CO2 are each split by a thermochemical process, driven by high-temperature heat (>1,500°C) produced using a parabolic dish that concentrates sunlight up to 2,000 to 3,000 times the usual intensity of the sun’s rays. This heat is captured by an absorbing material (metal oxide) that can reach temperatures of 1,500°C.
Water and CO2 are each split by a thermochemical process, driven by high-temperature heat (>1,500°C) produced using a parabolic dish that concentrates sunlight up to 2,000 to 3,000 times the usual intensity of the sun’s rays. This heat is captured by an absorbing material (metal oxide) that can reach temperatures of 1,500°C.
Light is concentrated by a parabolic concentrator to reach 2000-3000 times the intensity of the usual sunrays. The concentrated light is captured by an absorbing metal oxide material, which is heated up to 1500°C.
This heat is used to drive a cyclic thermochemical reduction and oxidation reaction: oxygen is released from the metal oxide (reduction) and then taken out of injected water and CO back into the metal while hydrogen and CO evolve (oxydation), and so forth.
Solar fuels
Hydrogene
CO
Gas storage (under pressure, in liquid form, or adsorbed to other materials) is not convenient and demands energy.
Thermochemical processes, such as the Fischer-Tropsch process or methanol synthesis, convert the H and CO mixture (called SynGas) into liquid fuel.
The captured CO2 used for production is released during combustion.
Photoelectrochemistry
Water and CO are each split by electrons and holes produced by solar light in a semiconducting material. Both concentrated and unconcentrated solar light work for this process. If concentrated light is used, the reactor can be smaller and more cost-competitive.
Water and CO are each split by electrons and holes produced by solar light in a semiconducting material. Both concentrated and unconcentrated solar light work for this process. If concentrated light is used, the reactor can be smaller and more cost-competitive.
Concentrated Photoelectrochemistry
Light is concentrated by a parabolic concentrator to reach 1,000 times the intensity of usual sunrays. The concentrated light is captured by a semiconducting material (like a photovoltaic device) and converts the sunlight into charge carriers (electrons, e–, and holes, h+). The reactor temperature is kept below 100°C.
Light is concentrated by a parabolic concentrator to reach 1,000 times the intensity of usual sunrays. The concentrated light is captured by a semiconducting material (like a photovoltaic device) and converts the sunlight into charge carriers (electrons, e–, and holes, h+). The reactor temperature is kept below 100°C.
Water + CO2
Producing hydrogen and CO or ethylene (or other C-based products) and O2 from water and CO2. Electron and holes are used to drive the electrochemical reaction, suppored by the catalyst.
Solar fuels
Hydrogen, CO, ethylene, or other C-based products
as feedstock for petro or argo.
as feedstock for petro or argo.
Biomass-derived components
Thermochemical process
e.g. Haber-Bosch or polymerization
e.g. Haber-Bosch or polymerization
Combination of thermochemical processes
Synthetic fibers
Plastics
Chemical process
(NH3 -based) fertilizer with N2 potentially from the air
Solar materials
Hydrogene
CO
Gas storage (under pressure, in liquid form, or adsorbed to other materials) is not convenient and demands energy.
Thermochemical processes, such as the Fischer-Tropsch process or methanol synthesis, convert the H and CO mixture (called SynGas) into liquid fuel.
The captured CO2 used for production is released during combustion.
What if it happens?
1×
Parabola
Photoelectrochemistry
Off-grid house
One parabola with a diameter of 5-7 meters can produce
enough hydrogen, low-temperature heat (80°C), and
electricity to meet the needs of a family. This solution
is considered pertinent for off-grid homes, such as a house
located in the mountains or on a small island. Some of
the hydrogen produced in the summer can be stored and
reused in winter to meet higher energy demands.
SwissEnergyInnovations
The Swiss Confederation funds 12 parabolic dishes to make 12 of the small islands of Vanuatu energy-autonomous through solar fuels. #RenewableEnergy #Vanuatu #DDC #InternationalCooperation #SolarEnergy
GreenEnergyFan
Incredible initiative! This is a great step towards sustainable energy solutions for remote areas. Kudos to Switzerland!
EcoWatchdog
This is just a drop in the ocean! Literally ;) Why aren’t we seeing larger scale projects that can make a real difference? This feels like a PR stunt.
CynicalObserver
Just before they get swallowed by the sea... what indecency to flaunt such projects while ignoring the impending doom of rising sea levels!
5×
Parabolas
Photoelectrochemistry
Self-sufficient Farm
Five parabolas, each measuring 5-7 meters in diameter,
can produce enough fertilizer to supply 3-5 conventional
farms in Switzerland. The hydrogen generated is converted
on-site into ammonia using a down-scaled Haber-Bosch
process, and then transformed into fertilizer. Similar to
agro-photovoltaic systems, these parabolas can be installed
on agricultural lands while allowing for livestock, market
gardening, or crop activities, and can even be beneficial
to them.
LaFermeDurable
Vente à la ferme : Venez acheter vos engrais locaux ! Soutenez l'agriculture durable et locale. Venez découvrir comment nous produisons ces engrais de manière autonome grâce aux matériaux solaires ! #AgricultureLocale #ÉnergieSolaire #EngraisNaturels #VenteÀLaFerme
GreenThumbsUp
Incroyable de voir une petite ferme adopter des technologies durables ! Kudos for this initiative
SoilSaver
I hope this technology is truly accessible and not just a pilot project. Small farms need sustainable and economical solutions.
FarmSkeptic
Super, encore un gadget pour fermes « branchées ». Pendant ce temps, la plupart des agriculteurs luttent pour joindre les deux bouts.
25×
Parabolas
Photoelectrochemistry
Steel processing plant
25 parabolas, 5-7m in diameter, can produce enough hydrogen
to support the steel processing activities (e.g. annealing)
of a mid-size producer. The hydrogen is produced locally,
thus eliminating transport issues and avoiding volatile market
prices. The hydrogen is stored in bottles at high pressure
and can be used for 24 hours of plant operation. The parabola
installation takes up less than 0.5 hectares and can be
located on the company’s parking lot.
SteelInnovations
Une usine de traitement de l’acier s’implante enfin en montagne dans le Haut-Valais ! Grâce à des paraboles produisant de l’hydrogène sur place, nous allions innovation et durabilité. #MountainInnovation #GreenHydrogen #SteelProcessing #HautValais
MountainTechEnthusiast
Super nouvelle pour la région ! C’est génial de voir des technologies vertes s’implanter en montagne.
EcoWarrior
J’espère que cette usine prendra vraiment en compte l’impact environnemental. La production d’hydrogène doit être propre de A à Z.
EcoWarrior
Une usine en montagne, vraiment ? Espérons que les paysages ne vont pas être gâchés par cette prétendue innovation.
1000×
Parabolas
Photoelectrochemistry
Fueling stations
1,000 parabolas measuring 5-7m in diameter can produce
enough hydrogen for 1 or 2 large fueling stations. Only 10%
of the area is actually taken up, and the rest (the area below
the parabolas) can be co-used by farming or other activities.
The hydrogen produced is stored in large tanks at a pressure
of up to 1,000 bar.
DairyInnovations
Thanks to agroparabolism, milk production and quality are increasing, even during heatwaves! Our cows enjoy the shade from the parabolas, ensuring their well-being and optimizing milk production, while we produce local hydrogen for one of the biggest fueling stations in Switzerland. #LocalFuel #Hydrogen #Agroparabolism #QualityMilk #AnimalWelfare #AgriculturalInnovation
HappyCows
What an excellent initiative! It’s fantastic to see how renewable technologies benefit not only human wellbeing but also animal welfare and product quality.
EcoDairyFarmer
I hope this method is economically viable for all farmers. It would be a shame if only large farms could benefit from it.
25000×
Parabolas
Photoelectrochemistry
Sustainable aviation fuel
25,000 parabolas of 7-9 m in diameter can produce enough
synthetic gas (hydrogen and CO) to be used in a Fischer-
Tropsch process to produce solar kerosene (about 100,000
liters) for a daily transatlantic return flight by a large airplane.
UAEAirportNews
The solar airport in the United Arab Emirates, a pioneer in sustainable aviation, is facing an unexpected situation: migrants have found refuge in the shade of the parabolas. #MigrationCrisis #SolarEnergy #HumanitarianChallenges
HumanitarianAid
It is crucial to address the needs of migrants with compassion and find sustainable solutions.
PolicyWatchdog
How could such an innovative project fail to anticipate humanitarian challenges? Better planning is needed.
1x
Parabolas
Photoelectrochemistry
Containers for fossil fuels
The most visible element of a fuel is its container. The objects you see here are in common use and have become archetypes. The jerrycan, designed in the 1930s in Germany, derives its name from “Jerry,” the nickname given by British soldiers to their German counterparts during World War I. Robust, stackable, and easy to handle, it was widely used during World War II and continues to be a global standard.
Originally crafted from heavy metal in the nineteenth century, gas bottles have evolved into lighter and safer steel designs, facilitating rental use. They feature safety valves and color codes that indicate the inherent dangers of the gas. A distinctive odor is typically added to the gas, which is odorless in its natural state, to assist leak detection.
Now less familiar to the general public, coal remains very present in industry. For example, it is found in the form of bricks made from compressed coal dust.
The hydrogen bottle
This bottle is not familiar to us. Industry employs this technical object to overcome a significant constraint: the low density of certain gases, particularly hydrogen. The latter only liquefies at the extreme temperature of -252.87 °C, which greatly complicates its storage and transport. To address this challenge, hydrogen bottles are designed to contain this gas under high pressure, typically between 350 and 700 bars. Hydrogen is flammable and explosive in air, hence the distinctive red color. Made from lightweight and durable composite materials, such as carbon fibers, they withstand high mechanical stress while minimizing weight.
4 scenarios for solar fuel containers
Hydrogen, produced directly or indirectly from the sun, is a promising energy carrier, particularly for local, decentralized, sustainable production. Its storage will extend beyond these bottles of compressed gas, taking on various forms: liquid hydrogen in cooled compartments, liquid synthetic solar fuels, solid hydrogen utilizing metal-organic frameworks (MOFs), for example, as well as other compression methods. Each method has unique characteristics and volumes, unlocking new potential uses tailored to different contexts. The four scenarios proposed below by the Industrial Design program at ZHDK explore these opportunities by reinventing archetypes of fossil fuel consumption. These speculative objects imagine a decarbonized, decentralized, democratic, diversified, and independent energy landscape.
Pipelines
The production of solar hydrogen–derived from water and sunlight–is potentially ubiquitous. Production is likely to move closer to where the energy is consumed, and therefore to inhabited areas. It could then become a visible and familiar part of everyday landscapes–expressive elements integrated into the structures and facades of buildings. The modular design system proposed here imagines the energy infrastructure as part of the architectural fabric. By incorporating Metal-Organic Frameworks (MOFs) directly into pipeline structures, hydrogen can be stored efficiently at lower pressures, reducing the need for bulky tanks or high-risk pressurization. These multifunctional structures transform passive architectural elements into active systems for the production, storage, and distribution of energy.
Drones
This concept speculates on a mobile, visible form of energy infrastructure, designed for off-grid communities and remote environments, such as alpine refuges, where traditional pipeline networks are unfeasible. These doughnut-shaped balloons, constructed from pressure-resistant textile membranes, serve as both delivery and storage systems. Floating above the ground, each drone is equipped with a coaxial propulsion system with counter-rotating rotors, enabling stable flight in complex terrain. Operating semi-autonomously, they can navigate independently or in coordinated swarms to reach isolated locations. By combining storage and mobility, they offer a flexible, decentralized solution for energy transport, capable of providing sustainable energy to remote locations.
Hydrogen Station
These service stations use parabolic dishes to produce hydrogen. The hydrogen is stored in bottles designed for personal mobility and various domestic uses. Their outer surface changes color as they are filled, providing a clear and intuitive visual indicator of the fill level. The hydrogen bottles can be easily refilled and exchanged at the production stations. Unlike traditional petrol pumps—isolated and purely transactional—these stations are transformed into interfaces or community centers for production and distribution. They promote a new interaction with energy, which becomes a shared resource that is integrated into the landscape and everyday life.
Pellets
These pellets store hydrogen in solid form, reframing the traditional log pile as a tangible and modular source of domestic energy. Compact and efficient, they are designed to power household appliances through a simple, hands-on process: users load a pellet into a reactor, initiating a process that generates electricity and heat, with water as the only emission. This approach provides clean energy by redefining and ritualizing domestic energy practices, emphasizing the preciousness of energy. The pellets require a measured interaction that physically represents the amount of energy needed. The system is particularly suitable for off-grid locations, where traditional infrastructure is absent or unreliable, and energy autonomy is essential.
Presented at mudac from March 21 to September 21, 2025, the exhibition Solar Fuels is part of the second edition of the Solar Biennale
- Exhibition curator: Scott Longfellow
- Steering Committee: Lukas Franciszkiewicz, Sophia Haussener, Jolanthe Kugler, Scott Longfellow, Julien Notter, WINT Design Lab
- Scientific research: Sophia Haussener – EPFL STI IGM LRESE
- Coordination: Romain Carré
- Graphic Design: Notter + Vigne (Julien Notter, Sébastien Vigne, Julien Savioz, Marke llic)
- Speculative Objects: Lukas Franciszkiewicz (ZHdK- Master & Research programme lndustrial Design) & WINT Design Lab (Robin Hoske, Felix Rasehorn) assisted by Finn Sauter, Julia Huhnholz
- Model making: David Zahner, Tim Frei
- Web Version: Stimul (David Mignot, Pierre Dumont)
Funded by the Swiss national science foundation
Ali images in the show belong to the public demain
