Electrical-energy storage into chemical-energy carriers by combining or integrating electrochemistry and biology

Our societies must reconsider current industrial practices and find carbon-neutral alternatives to avoid the detrimental environmental effects that come with the release of greenhouse gases from fossil-energy carriers. Our societies must reconsider current industrial practices and find carbon-neutral alternatives to avoid the detrimental environmental effects that come with the release of greenhouse gases from fossil-energy carriers. Using renewable sources, such as solar and wind, allows us to circumvent the burning of fossil energy carriers to produce electrical energy. However, this leads to a spatial-temporal discrepancy between production and demand, necessitating the ability to store vast amounts of electrical energy. Physical storage of electrical energy, such as hydropower and underground pressure storage, as well as the conversion of electrical energy into chemical energy, such as with batteries, can offer vast storage capacities. Another route of storing electrical energy at a massive scale is its conversion into chemical-energy carriers by combining or integrating electrochemistry with biology. Here, we will give an overview of the potential of these biological-storage technologies. Based on the order in which they combine or integrate biological and electrochemical steps, we will discuss the current state of research on these technologies in three distinct sections: (1) electrochemistry followed by biology; (2) biology followed by electrochemistry; and (3) integrated electrochemistry and biology. We will discuss research needs and opportunities in an outlook section at the end.