Semi-Biological Photovoltaic Cells

In this application we aim to harness photosynthesis, a fundamental biological process, and use it to convert natural sunlight into a utilisable form of energy with a biological photovoltaic panel. Using a multidisciplinary approach, we intend to prove the feasibility of biological photovoltaics for the production of hydrogen and/or electricity. A large amount of work has already been carried out in thefield of biological hydrogen production, but so far it has proven to be difficult to overcome the major technical hurdle that limits the commercialisation of this technology, namely that the oxygen produced during photosynthesis inhibits the production of hydrogen from the hydrogenase enzyme in vivo. Although there has been some interest in fabricating artificial devices with purified protein complexes to overcome this problem, these have not yet been shown to be economically feasible. In this application, we propose to separate the processes of oxygenic photosynthesis and hydrogen production in a semi-biological photovoltaic device using intact Gloeobacter cells. The device will essentially be composed of two chambers, or half-cells, so that biological material can harvest light energy in one chamber, and hydrogen can be produced in a second anaerobic chamber. This electrochemical approach to biological hydrogen production physically separates photosynthesis from hydrogen evolution, and by doing so, it prevents the oxygen produced during photosynthesis from inhibiting the production of hydrogen. In addition, this electrochemical approach can be used to produce a DC electrical current, in a manner analogous to standard silicon based photovoltaic panels; in this application we will also explore the potential of biological photovoltaic panels for the production of electricity.