A lot about the generation we could learn from the plants, which relentlessly for millions of years, turns water and sunlight into clean energy. Recently engineers at the University of Cambridge managed in new ways to mimic photosynthesis by using artificial leaves, in which as a fuel are the electrons of algae. It is claimed that a new invention is five times more efficient than the existing counterparts, it is much cheaper to manufacture and easier to use.
During photosynthesis, algae produce electrons in their cells, some of which are beyond its bounds, where “going to” with the help of special devices. Fuel cells constructed according to this principle, often referred to as biophotolysis elements (BPV). They generate energy by two main processes: acquisition (capture light rays to produce electrons) and electricity transmission.
In most fuel cells based on algae, these processes occur within one compartment. Scientists from Cambridge have realized that they can improve the efficiency of the device if to separate them.
“Accumulation and the transfer of power often have conflicting demands, says lees Kadi Saar, lead author of the study. For example, the storage device must be exposed to sunlight for maximum efficiency, whereas for energy transfer this is not required.”
In the end, a team of scientists has developed a device with two cameras, the first of which provides the necessary conditions for the production of electricity with the greatest efficiency, and the second allows to save the energy for later use, for example, after sunset.
“The separation of the processes of accumulation and transmission of electricity meant that we could improve the performance of the device by reducing its components, says Tuomas Knowles, co-author of the study. – Micro-scale liquid behave differently, which allowed us to create a more efficient elements, which have a low internal resistance and lower electrical losses”.
The researchers were able to achieve even greater efficiency and reduce losses of electrons in photosynthesis due to genetically modified algae. A new prototype of a received power density of 0.5 W/m2, five times more than in the previous project team.
This is a rather low value compared to the other photovoltaic elements, but the device on the basis of algae is more “green” alternative (in all senses). Their production is easier and cheaper, which is promising for use in developing countries.