One of the greatest problems facing mankind is the search for renewable energy. One potential solution is inspired by photosynthesis in nature. Photosynthesis combines water, carbon dioxide(CO2) and energy from the sun to store energy as sugar, which also releases oxygen. This principle is illustrated below.
Image source: National Energy Education Development Project (NEED)
The idea behind artificial photosynthesis is to create a man made system, or ‘artificial leaf’, that allows water and sunlight to react and form hydrogen gas(H2) to store chemical energy instead of glucose(sugar). This is significant because the hydrogen gas can be stored and utilized as a fuel source.
David Nocera of Harvard University explains the basic principle of artificial photosynthesis using an artificial leaf. Nocera also goes on to say that artificial photosynthesis still has to overcome high engineering costs to become commercially viable. Nocera’s lab is actively researching the topic to try and find more economical methods of artificial photosynthesis. Full David Nocera BBC interview below.
One review paper visually illustrates how a large scale H2 power plant could operate using sunlight and seawater as inputs. Also shown are green energy sources to enable the power plant to be completely self-sufficient and sustainable.
From Nature article: ‘Artificial photosynthesis for solar water-splitting’ by Yasuhiro Tachibana, Lionel Vayssieres & James R. Durrant
New research suggests that in addition to creating a hydrogen fuel source, artificial photosynthesis may be able to lower atmospheric CO2. This would require a system that more closely emulates natural photosynthesis, using CO2 as well as water and sunlight to create a type of hydrocarbon(contains both hydrogen and carbon) fuel. Atmospheric CO2 is a major contributor to climate change so this would effectively be ‘killing two birds with one stone’ as far as global issues are concerned. The possibility of reducing atmospheric CO2 further sells the case of artificial photosynthesis as a leading energy source for the future.
Artificial photosynthesis surely has some desirable qualities, but is it the solution to the global energy problem? Well, possibly, but not in the immediate future. A full switch to H2 fuel would be a long process involving engineering of new infrastructure for transportation, such as motor vehicle engines.
Research on the topic is fast evolving and it will not be long until artificial photosynthesis is highly efficient with cheap materials. The real challenge now will be turning laboratory research into a large-scale commercially viable energy source. Can we do it? Only time will tell.
-Dixon Leroux
