The UK is currently experiencing some prolonged windy weather and my all-renewable energy provider offers dynamic pricing. That means cheap energy and even negative-cost energy. This is where my HA instance shines and saves me a fortune on my power bill. Thanks again to the HA devs for this incredible project.
For the curious, I'm using bottlecapdave's excellent Home Assistant Octopus Energy integration via HACS.
If I had an EV it would make a huge difference. One of the really, really cool features of the Octopus integration is that you can create a binary sensor that triggers for the cheapest hours (consecutive or non-consecutive) between a set time period, so you could create an automation that works out how many hours your car needs to charge at, say, midnight, and have it only charge for the cheapest hours between then and 8am.