Very cool. Worth emphasising that there is a distinction between the power you buy from an energy supplier and the energy mix that is actually flowing in the lo

Very cool. Worth emphasising that there is a distinction between the power you buy from an energy supplier and the energy mix that is actually flowing in the local distribution network. Suppliers are responsible for delivering the right amount of energy to the transmission network for each half hourly period which needs to match the amount their customers are consuming. (This is estimated based on applying a set of models to customer meter data so there are multiple settlement "runs" carried out, some months after the HH period in question). Balancing within the half-hour is a service provided by the system operator which is currently a part of National Grid and for which a small charge is levied. Injecting too much power into the grid when the grid is net over-supplied or too little when the grid is net under-supplied leads to the supplier owing balancing charges. Stabilising the grid to prevent those under-deliveries or over-deliveries destabilising the grid is also the responsibility of the system operator. So if your supplier buys 100% renewable power but you live somewhere far away from renewable generation your power both is and is not 100% renewable. In a certain sense it is because the whole grid is connected and higher a % of renewable power is demanded, the higher a % has to be generated in the system. In another sense it isn't because some of the energy you consume is being supplied by non-renewable sources. Of course in the latter view you also have to account that other people who have not explicitly paid for renewable energy are receiving it because you have.