Our aim is to research and develop a totally new, environment-friendly, cost-competitive, grid-scale Electrical Energy Storage (EES) system, and apply this system in the existing electricity grid. This technology, referred to as “Blue Acid/Base Battery” (BAoBaB), stores electrical energy using pH and salinity differences in water. The principle of BAoBaB is altering the acid-base balance by means an excess of available electricity to obtain an acid and base from its corresponding salt. When electricity is needed, acid and base are recombined into their corresponding salt again while obtaining electrical work from the entropy and enthalpy gain. The energy density stored in such osmotic and pH-gradients outcompetes, by an order of magnitude, pumped hydropower, which is currently the leading technology for large scale electrical energy storage. In combination with the wide applicability (no geographical limitations) and scalability (operational in a range of kW-kWh up to MW-MWh), this innovative technology is attractive for stationary electrical energy storage. It is safer and more sustainable than other battery technologies as it does neither contain toxic chemicals nor scarce elements.
Our goal is to develop this next generation storage technology from ‘proof of concept’ (TRL3) to ‘validated in relevant environment’ (TRL5). Our objectives in this research and development project are:
1. to establish and extend the potential of BAoBaB to become a reliable and environmentally friendly way of storing (renewable) electricity at kWh-MWh scale for application at user premises or at substation level.
2. to understand and enhance mass transfer in round-trip conversion techniques and hence to improve the energy conversion efficiencies of the BAoBaB system. We aim at developing the BAoBaB with competing performances to pumped hydropower storage (PHS) by obtaining energy conversion efficiencies of over 80% and >10 times higher energy density.
3. to validate under accepted utility use conditions an automatically operated BAoBaB system (with corresponding battery management) at a scale of 1 kW power and 7 kWh energy storage.
4. To pave the road for cost competitive energy storage with attention to life-cycle cost and performance. The BAoBaB system, including all the subsystem components, installation, and integration costs need to be cost competitive with other storage or non-storage options available to electric utilities or other end users. The aimed potential levelized cost is <0.05 €/kWh/cycle, which would be an economically scalable EES without subsidies.
 Assuming a PHS with an average head of 200 meters water column (energy density ~0.5 kWh/m3)