One example is producing hydrogen from water with excess power. It can then be added to the natural gas network, or used by trucks or trains, or stored for a power plant.
It's great when we can use off peak energy for things like this, but they're not as easy to locate onsite as bitcoin miners .. and difficulty with transmission is a big part of the problem
If you don't understanding anything about Bitcoin's properties and the utility that provides, I can understand why you would think its a waste of energy. But many disagree with you for good reason.
Some people think clothes driers or Christmas lights are a waste of energy, but it's not for them to decide how other people spend the energy they've paid for. Some people think those things are worth the energy cost and so they pay for it. That's their choice to make.
Burning the planet? I assume you mean CO2 emissions.
Bitcoin has one of the highest % of renewables of any industry i.e. solar, wind, hydro etc.
As an absolute value the amount of energy it consumes is less than 0.1% of global energy consumption.
Those two things taken together mean that Bitcoin contributes what amounts to a rounding error in total global CO2 emissions.
And that's not even mentioning its GHG emissions reducing effects on the capture of methane, which could turn it CO2eq negative emissions.
On top of that it has an important role to play in balancing grids by consuming excess energy that the market doesn't want or need, or can't be stored.
And the utility of Bitcoin? Well, some people see value in a form of money that can't be arbitrarily debased, is open to all on a global and neutral network that can't be changed or controlled by any central or corrupt authority, and that is censorship resistant.
You might not see value in that, but many people do.
Maybe you see more value in Christmas lights which consumes more energy than Bitcoin.
If you live in a developed market with no need for the utility bitcoin provides, then to you bitcoin is only a waste of energy, and energy generation is a significant contributor to greenhouse gas emissions. In this case you see it as all cost and no benefit, and any counterpoint goes against your dogma, which is 'inconvenient' or irritating
