Our research aims to understand the unsteady aero and hydrodynamics of wind and tidal turbines, and to underpin the design of more durable and efficient technology. We have investigated the main sources of unsteady loadings for tidal turbines (Scarlett and Viola 2020), and we showed how large but realistic ocean waves can lead to the largest load fluctuations (Scarlett et al 2019). Inspired by the extraordinary abilities of birds to fly in turbulence, we study morphing blades that can mitigate load fluctuations without compromising the mean load and thus the power harvested by wind and tidal turbines. VOILAb is currently leading a £1M project funded by the UK Engineering and Physical Science Research Council, to demonstrate at model-scale a novel technology to reduce unsteady-loading for wind and tidal turbines, improving resilience and reliability, and decreasing the levelised cost of energy of these two critical reneable energy secotrs (Grant no. EP/V009443/1).