[_ph_]

Solar doesn’t provide nearly as much energy and for desalination you need a surprising amount.

That statement doesn't make any sense to me. If you need more power, install more panels. Space certainly isn't an issue in like northern Africa. It is cheaper to order a gigawatt or more of solar panels than building a new nuclear reactor, and faster to set up too. Even Germany today has way more solar capacity than it ever had in nuclear, and it is less a great place for solar than Africa.

[akiselev]

The vast majority of our freshwater comes from sources that cost us effectively zero in energy: the water cycle moves water towards higher elevations and it flows down towards our populations. Worst case scenario, water in ancient underground reservoirs is pumped to the surface.

If we had to desalinate all that water and actively distribute it instead, it'd be a significant fraction of our current global power consumption. The power sources need to be concentrated near the desalination plants and at least half the world lives 100km+ away from a coastline. At 3 kWh per m^3 of water[1] and ~3.5 m^3 per person per day [2], that's an extra ~3800 kWh per year, which would increase per capita energy consumption by 25-30% [3] in the United States just for desalination.

We have enough challenges replacing existing power infrastructure with solar and wind. Placing the burden of desalination on top of that is unrealistic, especially since the NIMBY fight over solar installations of that size would probably be just as fierce as for a nuclear reactor.

[1] https://res.mdpi.com/d_attachment/energies/energies-12-00463...

[2] https://www.usgs.gov/special-topic/water-science-school/scie...

[3] https://data.worldbank.org/indicator/EG.USE.ELEC.KH.PC?locat...

[_ph_]

I have never claimed, that we would replace all fresh water used on this planed by desalinated water. This certainly is neither feasably nor necessary. At best, it can be an important contribution to water supply in many regions.

I was only answering to the original post which suggested we would build nuclear power plants to desalinate water. There I commented that solar would be cheaper (and more environment friendly) for the same task.

[scraptor]

> Even Germany today has way more solar capacity than it ever had in nuclear

That's because it never had much nuclear capacity, not because it now has a lot of solar

[_ph_]

I don't know what you mean by "much", but Germany has a peak power capacity of 56 GW of Solar. On good days the output comes close to the nuclear output of France, which is mostly nuclear in power production. German wind power occasionally eclipses French nuclear power production.