On the other hand, do we have any idea about how long Nuclear power will last, If we produce lets say, 50 percent of all our energy needs from it ?
This is hard to estimate precisely, since we don't know how much uranium is yet to be discovered. At the low-end, using current estimates for mineable Uranium, and today's light water reactors, about 460 years. At the high end, using newer breeder reactors and extracting uranium from seawater, as much as 240,000 years. Using a reasonable estimate for mineable uranium, and newer breeder reactors, about 120,000 years.
Let's be conservative and say "at least a few thousand years".
Personally, I'd say if we can't get off Earth and find some new fuel sources in a few thousand years, we deserve whatever happens. And frankly, if it takes us more than 200 years to get useful fusion reactors, something has probably gone wrong, and we're back to burning wood in caves anyway.
Here's a source: https://www.scientificamerican.com/article/how-long-will-glo...
There they estimate a 230-year supply at today's consumption rate. Nuclear energy currently supplies 4.0% of the global primary energy production [1]. According to that estimate, producing 50% of the primary energy using currently available reactors would exhaust the world Uranium supply in around 18 years.
The sun will keep shining 10.000 years from now, there is no need to move of the planet to find new fuel sources if we just keep letting the sun shine on us.
It doesn't take much storage to operate solar in a "baseload" manner. Already, most new utility scale deployments are shipping with storage.
For a long long time, the DC electricity side of a solar installation has been cheap enough that the design of a system will have an 20% extra DC over the capacity of the inverters change the DC to AC electricity for the grid. As panels have gotten cheaper, this loading factor has creeped up to 1.5 and 1.6 in many installations.
Since battery storage is also on the DC side of the installation, adding storage of the doesn't even require adding more panels, it can just use the existing clipped solar energy. And when we start adding more panels to get the loading factor up to 2 or 3, the solar power installation becomes nearly completed dispatchable to meet grid needs. This is simple and straightforward changes of parameters in existing designs.
It does sometimes get cloudy for days on end which reduces solar output to about 10-20%.
However, if there's need for more, then the storage side could be expanded. Personally, I'd like to see a ton more expansion of solar and storage behind the meter, at people's homes and at industrial and commercial sites, so that we can reduce the need for transmission and distribution. The US stats for electricity costs are something like $0.13/kWh on average, with $0.05 of that from generation costs and $0.08 from T&D. Even if installation costs are slightly higher at smaller, more distributed sites, T&D isn't cheap either. And having more distributed generation and storage as the potential to greatly increase reliability, particularly after natural disasters.
Distribute your solar across multiple geographic locations
> seasons which have significant swings in solar productivity.
Install enough panels so that in the seasonal lull you still have enough power. Panels are super cheap these days.
Solar panels and storage are on learning curves just like integrated circuits are for Moore's law. We are seeing absolutely astounding drops in cost every year, and innovation is happening continuously.
The future world of renewables energy is one of extreme energy abundance. We will size our generation so that in the seasonal lulls we have enough energy, which means that in the rest of the year we are going to have absolutely massive amounts of energy available that's near to zero-margin cost (assuming you can move your electricity consuming application to be close to the generation site, since transmission will still be expensive). And this curtailed electricity has far more potential uses than the waste heat that comes out of a nuclear plant or a coal plant.
Why do you think Germany is signing multi-billion/multi-decade contracts to ship Russian gas if solar/wind+storage is a solved problem?
You need to be precise with how you talk about the shift in energy demand due to EVs. It's not a net energy increase. EVs are far more efficient than gas vehicles. I assume what you mean is increased electricity demand. You can back this out based on typical driving metrics - 250wh/mile is a typical efficiency for electric vehicles. If each driver does 10k miles/year and there are 200M drivers in the US, then this equates to a 13% increase in electrical demand for full adoption[1]. You could probably add on 2% more for efficiency losses in transmission and charging, so call it an additional 15%. That's effectively worst case as it assumes no reduction from the removal of the current infrastructure(ie pumps for gas pipelines, heating for refining, trucking, etc). Those are huge users of energy (though much in forms other than electricity). Oil refinement alone accounts for ~4% of all energy use(not just electricity) in the US.
EVs are so efficient, transitioning to them will probably consume less energy than just the energy we currently spend producing and distributing gasoline. We'll probably need to add to electrical infrastructure, but compared to the savings that is easily justifiable.
[1] https://www.wolframalpha.com/input/?i=250+wh%2Fmile+*+10000+...
My question is: When the shift has been completed, how many of today's natural habitats will still be standing? I'm not asking how about solar's efficiency.
Nuclear has the same bootstrapping problem as any other power source, but it also has the problem that we don't yet have a way to produce concrete without emissions, and our carbon-free steel methods are still in their infancy, and those are serious inputs to any new nuclear build.
And what do you do at night, or on a cloudy day?
There is no grid-scale storage solution.
> And what do you do at night, or on a cloudy day?
https://insideclimatenews.org/news/16012018/csp-concentrated...
It shouldn't be a surprise that they are the same family, solar is really the only electricity generation solution that scales down nicely for remote places.
Solar fails at high power density applications, like airplanes, not remote ones. I suppose it also fails at "remote and north of the arctic circle/south of the antarctic circle" ones, but that's a pretty tiny rounding error of energy usage.
On the contrary. Shipping diesel to remote Alaskan villages is so incredibly expensive, even with subsidies, that they're seeing a boom in solar power even that far north.