AT the moment, renewable energy is extremely expensive, impractical and completely unsuitable as the main (let alone only) source of electricity.
Many people hope that over the next few decades with enough money spent on giving state benefits to people who use renewable energy and companies who supply the equipment, renewable energy will become cheap and abundant. There are possibilities on paper, e.g. wave and tidal in Scotland alone could on paper supply enough electricity to power the whole of the UK. On paper.
But on paper nuclear fusion could, in the same sort of time frame and with lower development costs, supply a ludicrous superabundance of electricity to everywhere until the end of the world. With that degree of energy surplus, all sorts of additional things become possible. You're probably aware that there are concerns about freshwater supplies for the future even in richer countries and you must be aware that the lack of them is killing lots of people in poorer countries right now. The problem goes away if you have so much spare electricity that you can desalinate and purify sea water and not care how much energy it takes. Hydrogen is an extremely inefficient energy carrier, which is why it's currently worse than useless for providing highly localised electricity generation for things that could use it (most obviously, cars). That problem goes away if you have so much spare electricity that you can just split hydrogen off from water and not care about how energy it takes. That's just off the top of my head - I'm sure other people could come up with far more applications for having a vast superabundance of electricity.
Also, there's a lot to be said to generating most of a country's electricity from sources that can be controlled by people (i.e. not wind, waves, sunshine or any other renewable).
It's funny really, almost the exact argument was used against nuclear less than ten years ago. Nuclear is/was a lot more expensive than fossil fuels and was/is subsidised to some degree.

