Definitely been some good progress on this in the last four years, smart meters are rolling out, EV's and renewables continuing to rise. Unfortunately the majority of EV's on the market right now do not support vehicle-to-grid (V2G), only Nissan's EV's as far as I know. And there still needs to be more research into what sort of effect V2G has on battery degradation.,(reply>), And even for those that have Nissan EVs, the V2G technology to connect it to the system, and make use of that balancing service is still largely unavailable. I am aware of the Indra trial, which is a Vehicle-to-Home scheme that will make use of time shifting with variable domestic prices - but its still a trial - do such technologies yet exist?