It's not exactly "free"
There is a LOT of maintenance, not to mention initial investment, in setting up a geothermal power station.
Same for any kind of power plant.
Nukes produce a lot of "free" electricity if you ignore the investment, maintenance, and disposal costs.
Solar power is likewise extremely costly.
You're right. PPL use the term 'free', not in the sense that it costs nothing but that it is free of the use of hydrocarbons. In the case of Iceland they have geothermal "steam geysers" or whatever they are called that are used to produce electricity and heating buildings. They were getting the electricity anyways so it was not a big problem to add the hydrogen production to the mix because in the night time electrical usage goes down.
I used to work with a lot on engineers when I worked at a massive hydroelectric facility in Northern Canada so I am familiar with the notion that electrical usage is lower at night and also that wind power is not reliable as it tends to swing up and down so much that using it for normal electrical grid is dicey at best. Sort of like if your car engine speeded up and slowed down constantly. Electrical devices need steady clean power.
I personally don't care the source of energy, but simply the cost of it. I have friends who are absolutely onboard with the Paris Climate Accord but keep their house heated to the point of being 'tropical'. The whole carbon thing is nonsense IMO and is being touted by PPL like Al Gore because he has a company on the LSE that trades Carbon Credits.
If you read GWs books you will see that there is a lot more to the various technologies than magnets and the other silliness that PPL have mentioned here.
Public ridicule doesn't count in my world. I had an enlarged prostate years ago and it was treated by someone who is now my friend. In one treatment he fixed it, for free (and it it is still fine) with no pain and no strain, and none of the horrible side affects that another (naysayer) friend of mine suffered by getting treated by the "medical establishment". My wife and I also had arthritis and now it's gone with alternative therapies. I had a liver issue (alinine transaminase too high) and now it's gone. I am 66 and only wear reading glasses occasionally thanks to an alternative medical therapy. I fix my wife's sciatica when she overdoes gardening. I fixed my hypothyroid drug free. I've fixed tennis elbow, the list goes on. My prostate is now fine and what a relief, so new ideas are something that I look past the garbage on the internet made up by naysayers. I seek out all the choices till I find one that works.
If I gotta spend 100 dollars on a book or a therapy, big deal. What would I spend on a lifetime of misery from a prostate surgery or a lifetime of pills for hypothyroid or a lifetime of living with a messed up liver or poor vision or a wife with arthritis and sciatica. I've fixed other stuff including tricking out my house to save electricity. It's just a challenge to me.
All I care about is hearing from PPL who have actually tried it and did it carefully so that it worked. Most therapies work but not necessarily with everyone or in every case.
Years ago I was having a hard time deciding whether I should buy a diesel rabbit when they first came out so a wise friend of mine said "just write down a list of the positives and negatives of the idea and then compare. If the positives are greater, then do it". Sometimes I try things that I lose money on, but more often than not I win big.