I have a super low-wattage one, its 600w. That means it boils water quite slowly BUT.... even on a cloudy day, my solar panels create enough free electricity to run it. So free cups of tea! I also fill a mug with water, pour that into the kettle and boil it - not one unnecessary drop of water is heated. I'm very pleased with my setup. (If I had a 3000w standard kettle I'd get my drink 5 times faster but would need to pay to import the power unless it was a really sunny day).

I have one similar to this and I recommend a glass one so you can see when it boils from anywhere in the kitchen.

We've had two of these since 2009. The first one lasted up until a few years ago then failed. We couldn't find one which was as good so we bought the exact same model again.

It boils a cup of hot water very fast. What I like about this one is I can take it off the stand to fill up. Most eco kettles are stationary. The boiler chamber is at the bottom so wasted heat goes back into the water tank. It's designed to reduce waste.

https://www.asda.com/groceries/product/kettles-coffee-makers/breville-hotcup-hot-water-dispenser/3598743

Bosch Styline Variable Temperature Cordless Kettle - £50

Sounds not worth it, but I go for green tea quite a bit, which is best at a lower temperature (80°c), and it can also just boil water normal (100°c)

I've had it since lockdown, no troubles with it

Still recommend my VonShef from a few months back: https://feddit.uk/post/41485772

A shit £10 kettle will last 10 years, and a nice fancy one that matches the colours in the kitchen and costs £30 will last 3 years.

I assume there's some higher price bracket where the durability goes up again.