But even if you can't easily get to 90% why not celebrate the fact that 75% is easy. Sure the last 25% is hard, but 75% good news and 25% bad news is not what I see in the news articles.
Breeders are from an obsolete vision of the future where we'd have an order of magnitude more nuclear power plants than we do now. In that future, uranium would start to be in short supply. But that didn't happen, uranium remains cheap, and breeders have no business case.
New offshore wind projects in the UK contract to produce power at about 40% the cost of new nuclear, about the same as gas before the Ukraine war interruptions. And that’s before the 45% construction cost overrun on Hinkley Point C that EDF is responsible for.
Onshore wind would be half the price of offshore but we’ve stopped building it because Tories.
Over provisioning a mix of renewables is likely the most cost effective route to greening the electricity supply.
Modelling for Denmark shows over 90% of its electricity consumption could be provided through modestly over provisioning renewables 1.5-2x along with 4-12h of storage and 99% with 3-4x over provisioning renewables and 48h of storage.
Sadly incorrect. You can see the variation of wind and solar we get here in the UK at: https://gridwatch.templar.co.uk/
As you can see, fossil fuels are about a 1/3rd of power and we expand renewables by maybe another 30% before we start getting excess power. After that point, you start to have excess power while no longer reducing CO2 by much as you still need the Nat gas for the cloudy and still days.
In practice you might be able to get to 75% non-fossil fuels before you're firmly into the realm of diminishing returns without a big storage breakthrough or a doubling/tripling of electricity costs (its triple to go pure wind and current tech energy storage because you need up to weeks of storage to not have blackouts, but with a nuclear power expansion youd only need a doubling).