Renewable energy is taking off at exponential rates, putting global clean power "in line with ambitious net-zero scenarios." A new report suggests fossil fuel demand in the energy sector has already peaked, and "will be in freefall" by 2030.
Renewables surprisingly "on track" to meet net zero by 2050::undefined
The core issue is grid-scale storage. Adding 10 or 30% renewables is easy and is where we currently are, getting to 100% means we need to solve that technology issue which we don't currently have a solution to.
Nuclear + renewable is the current way to de-carbonize the grid. Build both heavily until we solve the technological issue with grid-scale storage in the coming decades.
On the timescale of 27 years, grid-scale storage is going to be a complete non-issue. There's already a decent amount of work being done at that level right now and battery tech has been improving at a consistent pace. Renewables can work quite well as-is with a good mix of location and source. Offshore wind is more consistent wind speeds, solar locations can mitigate light cloud coverage, solar output peaks during the times of greatest human use, and land based wind is typically dispersed over large areas.
I'm a huge proponent of nuclear power, but as things stand it isn't going to be necessary on these time tables. The value in nuclear is that it's another thing we can build now without needing to wait ten years for battery prices to continue to decline or for manufacturing capabilities to ramp up. Building 10 GW of nameplate capacity wind+solar is great. Building 10 GW of nameplate wind+solar and 5 GW of nameplate nuclear is better! That's the advantage of nuclear today, and we should fucking make use of it. That doesn't make it mandatory in the long-term.
The only current storage technology cheap enough if you happen to have the nice problem of having to curtail renewable production during peak is water electrolysis -- if you also happen to have the natgas storage and distribution infrastructure already in place.
MWh and GWh scale battery infrastructure isn't cheap at all. It will likely take a decade to have affordable 10 kWh scale domestic storage, and it will be most likely sodium, not lithium. 100 kWh scale, which is almost enough for seasonal demand levelling will still take pressurized hydrogen in cylinders.
HVDC links between countries will also make renewable energy transmissible to places around the globe that need it, so sun shinning in one country can be transmitted to where the demand is.
Hydro is pricey, and wind/solar is catching up so. China unsurprisingly has the largest capacity of hydro, more than US and Canada combined. B.C., Manitoba, Quebec, Newfoundland and Labrador, and Yukon typically generate over 80% of their electricity from hydroelectricity. We have some sizeable dams (5000mw), but nothing on China (22,000MW). We have a dam being constructed in BC and it's going to be like 16billion dollars. I'm sure you could do a lot of solar/wind for that price.
Alberta, Saskatchewan, Nova Scotia, and Nunavut generate most of their electricity from fossil fuels such as coal, natural gas, or petroleum. Alberta used to generate about half of their electricity from hydro and moved away from it. They are starting to invest in solar/wind.
Adding even 10% of renewables (minus biofuels since fake renewable) to primary energy use of major industrialized countries is by no means easy. Which is why world fossil fraction of primary energy use is nearly a constant.