Big floating solar islands on the ocean that produce adequate energy to make it possible for CO2-neutral worldwide freight traffic – what seems like “science fiction” scientists from ETH Zurich, the Paul Scherrer Institute (PSI), Empa, the Universities of Zurich and Bern and the Nowegian University of Science and Technology (NTNU) in Trondheim have actually now determined for the very first time, as they compose in the most recent concern of the journal “Proceedings of the National Academy of Sciences” (PNAS).
Paper, can, glass – the world recycles as much as possible. So why not state the greenhouse gas co2 (CO2) a recycling item also? Liquid fuels based upon carbon will continue to play a crucial function in the future – in spite of worldwide efforts to lower them. So it appears reasonable to recuperate the CO2 exhaust from the environment and utilize it once again.
Scientist from ETH Zurich, PSI and the Universities of Zurich, Bern and the Norwegian University of Science and Technology (NTNU), together with a group from Empa, have actually determined this concept and have actually revealed that solar methanol islands might produce adequate fuel in the long term to make all CO2 given off from transport sources neutral – worldwide. In the middle of the oceans, hydrogen (H2) is to be produced from solar power (and water), which is then transformed into methanol on website utilizing CO2 drawn out from the seawater. To this end, the scientists evaluated in information a situation that still appears simply theoretical, however currently offers the basis for a possible execution. They provide their lead to the journal “Proceedings of the National Academy of Sciences” (PNAS).
From sun to electrical energy to hydrogen to methanol
The concept is based upon solar islands, i.e. floating platforms geared up with photovoltaic systems. Nevertheless, considering that solar energy cannot be kept and carried from there, a solar energy plant on the sea makes no sense. Liquid methanol (CH3OH) in addition to gaseous methane (CH4) can be produced from co2 and hydrogen. The scientists’ concept is that the raw products might be acquired straight from the ocean or produced there.
There are currently massive power-to-gas plants that transform hydrogen and CO2 into fuel – consisting of the “move” presentation platform on the Empa school in Dübendorf (see box). The concern for that reason occurs: why go to sea with it? Why not, as existing plants do, draw out CO2 from the air? The response is basic: the space needed for an around the world supply of fuel would be huge. “An area of around 170,000 km2 would be needed to produce the annual demand for global freight transport,” describes Andreas Borgschulte of Empa’s Advanced Analytical Technologies laboratory. This might best be accomplished by solar energy systems at sea, a formerly unused location that does not come from anybody. CO2 can likewise be drawn out from the air at sea, however an appealing – and still apparent – option would be to utilize the approximately 125 times greater CO2 concentration of seawater for the “carbon dioxide harvest”.
More possibilities for methanol
In existing plants, the CO2 drawn out from the environment is mainly utilized to produce methane, which would likewise be possible on the solar islands. In the course of their factors to consider, nevertheless, the scientists chose to produce a liquid fuel due to the fact that it is simpler to transfer. In addition, methanol can be utilized not just as a fuel, however likewise to make other chemical items, such as precursors for polymer production. The possibilities for its usage (and the revenues that can be accomplished with it) are for that reason much higher.
Nevertheless, such a “methanol island” has its cost: the building and construction of such a chemical plant on the ocean would cost around 90 million United States dollars. This would include around 70 photovoltaic islands with a size of around 100 m2 and a ship with the electrolysis and synthesis plants. This would lead to an overall location of around 550,000 m2. However a single cluster is far from adequate to attain a no balance of CO2. An overall of 170,000 such islands would be required to recycle as much CO2 as is presently given off – a utopian objective, however one worth pursuing. “Great ideas are needed – small solutions only supply small parts of the world, but not all of it,” states Borgschulte.
How to keep electrical energy over longer amount of times – “power-to-gas” and “power-to-liquid
Empa has actually long been investigating methods of not just saving electrical energy from sustainable resources, however likewise transforming it into liquid or gaseous fuel. The Empa school in Dübendorf is likewise house to the “move” presentation platform. There, solar electrical energy is transformed into hydrogen with the help of electrolysis in order to refuel hydrogen lorries with it. Artificial gas, which is utilized in gas lorries, is likewise produced there. Empa scientist Andreas Borgschulte and his group are dealing with methods to more enhance these innovations. More info here.