[pif]

> we either need a radical new source of apples, or we need to find a way to use far fewer apples.

I'm afraid that in no way we can have the second without the first one. People switched to fossil fuels because life was way too much easier with them, and no climate change can convince us to go back unless we find another big source of cheap energy or, simply, we exhaust the oil fields.

[madaxe_again]

We basically need portable fusion, or micro-hydrogen turbines powered by hydrogen formed by electrolysis of seawater from purely renewable sources. It's quite an ask, given that, as you say, fossil is cheap and easy - although not as cheap as it used to be to get at - but artificially cheap on the market in a (in my view) desperate lunge to stave off the inevitable fall, as their real production costs catch up with them. There's a reason they're investing increasingly in "alternative" energy sources, and moving branding towards energy from fossil fuels. The market will act, but I fear too late.