European Utility Week is the largest gathering of energy companies and suppliers in Europe. In this video report James Westley looks at how the variability in the supply of renewable energy from solar and wind is driving innovation in energy storage technologies. Conventional batteries may be your first thought, but they are by no means the only form of storage. James looks at two companies whose innovative products are entering customer trials. Stornetic were showing their EnWheel® kinetic energy storage device, and Kemwatt their flow battery. Both technologies have their role in the overall storage strategy an a power system and both are excellent examples of the innovative opportunities in this sector.