Since the early 1970s, scientists have been on a quest to develop a technology that could create liquid fuels out of carbon dioxide, water, and sunlight far more efficiently than photosynthesis, the process by which plants harness sunlight to produce carbohydrates and store energy. They call it the artificial leaf.
In an industrial greenhouse about 30km from Zurich, plump aubergines and juicy cherry tomatoes are ripening to perfection. Growing Mediterranean crops in Switzerland would traditionally be energy intensive but these vegetables are very nearly carbon-neutral. The greenhouse uses waste energy from a nearby refuse plant, and carbon dioxide from the world's first commercial direct air capture plant. The facility, designed by Zurich-based start-up Climeworks, pumps the gas into greenhouses to boost the plants' photosynthesis and increase their yield, it hopes, by up to 20%. Climeworks says it will extract around 900 tonnes of CO2 a year from the air.
Researchers at Harvard University have created a system that allows them to store the energy of the sun, converting solar energy into chemical energy using a hybrid mechanism of inorganic chemistry and living organisms. Comparing their invention with the natural process of photosynthesis, they refer to it as a "bionic leaf" or "artificial leaf," and they say the level of efficiency they have achieved far exceeds that of other similar systems – including photosynthesis itself. The paper, published Thursday in the journal Science, describes the work as addressing two fundamental goals: storing the energy of the sun, rather than merely converting it for immediate use, and building something useful from carbon dioxide in the atmosphere, thereby reducing a major greenhouse gas. "I think this is actually quite exciting research," Johannes Lischner of Imperial College, London, who was not involved in the study, tells The Christian Science Monitor in a telephone interview. "Converting sunlight into chemical fuels with high efficiency is something of a holy grail for renewable energy."
A team of scientists at Harvard University says it has come up with a bionic leaf -- a system that could use solar power and hydrogen-eating bacteria to generate liquid fuel. The findings, described in the journal Science, offer an alternative path to making carbon-neutral solar fuels. Part microbe and part machine, the bionic leaf marks a tenfold improvement on the researchers' previous version and could be used to generate all kinds of products, from the precursors for bioplastics to fuel. "This work is quite significant. "In addition, being able to do this at low pressures and at high oxygen concentrations represents another major advancement."
Millions of island-like solar farms could help suck CO2 from the atmosphere and repurpose the gas into synthetic fuel, say researchers. In a new paper, scientists from Norway and Switzerland propose the construction of 11 million'marine-based artificial islands,' each as big as a football field, to help mitigate the disastrous effects of carbon-based fossil fuels. To achieve their goal, the futuristic'islands' would come equipped with a host of technologies, some existing and some not. Using photovoltaic cells, for example, researchers say the giant hubs could convert sunlight into electricity, which would then be used to power the extraction of hydrogen and CO2 from seawater. Floating solar energy farms aren't entirely new, but a recent proposal would bring them one step further with technology that can convert CO2 in seawater to synthetic fuel.