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.
I'm surprised, to be honest, since I worked out a while ago that if I had an EV - even something like a Zoë doing 20 miles a day - I'd be saving a lot of money, but if you've done the maths then fair enough. Keep in mind, though, that since you're alreay with Octupus you could just switch to Agile for a month and switch back if it doesn't work out.