1.5kWh of energy, not power.
And it’s not lifting 500 tons. Each bucket weighs 500 tons (regardless of boat or no boat, due to displacement physics), it is in almost perfect balance. The motor simply has to rotate the mechanism against frictional losses.
Yes, people frequently get it wrong and when they are dismissive about it, they are demonstrating their lack of willingness to educate themselves.
It may seem like semantics to quibble over technical language but if I ask someone to pass me a saucepan, when I want to use a frying pan, then it’s pretty stupid of me, isn’t it?
I’m only an amateur but I’m happy to give it a go
Battery lifetimes are specced as 80% capacity remaining. So a 300 mile range becomes 240 miles. Still highly usable.