[Gwypaas]

The thing is, they don't complement each other at all. They both compete for the same share of the market: the cheapest most inflexible power generation. Renewables win there and force nuclear plants to be more flexible.

Due to the extremely high fixed costs and lower marginal costs of nuclear plants they then have to make the money back in fewer hours, driving cost even higher.

The other issue is the costly steam turbine side. The reason gas won over coal is the efficiency and tiny footprint of gas turbines. Tack on a tiny steam side for the last percent of efficiency and you have a CCGT plant. Coal and nuclear share the same steam side, both have been dead ends since the 80s.

[exabrial]

That is not true. They do not compete for the some market segment.

The problem is most renewables fall off before peak load subsides. That's why cheap energy storage would be a huge boon for transient renewables as they could keep providing energy after the sun is down and the wind has subsided.

Take a look here: https://nuclear-power.com/wp-content/uploads/2017/08/Base-Lo...

[Gwypaas]

They do. This graph shows the nuclear "baseload" being crowded out of the market by cheaper renewables. (Or in this case mostly coal, but they are about equal on the electricity market in terms in inflexibility and cost structure.)

https://en.wikipedia.org/wiki/Base_load#/media/File:Renewabl...

So, this means that nuclear is crowded out of the market during the sun hours, and later all windy hours. Take a low-ball nuclear cost of ~$130 per MWh. [1] Say that wind + solar can fulfill 12 hours per day, this is a low estimation. Current estimates is that ~80% is easily feasible without storage.

That means the nuclear plant has to make do with the 12 hours left. The nuclear plant has now, based on napkin math, entered a LCOE of $260 per MWh. It was already hilariously uncompetitive at $130 per MWh, now try $260. Now you can do power 2 gas and then burn it or any other extremely inefficient energy storage and still come out ahead.

> While historically large power grids used unvarying power plants to meet the base load, there is no specific technical requirement for this to be so. The base load can equally well be met by the appropriate quantity of intermittent power sources and dispatchable generation.

> Grid operators solicit bids to find the cheapest sources of electricity over short and long term buying periods.

> Nuclear and coal plants have very high fixed costs, high plant load factor but very low marginal costs, though not as low as solar, wind, and hydroelectric. On the other hand, peak load generators, such as natural gas, have low fixed costs, low plant load factor and high marginal costs.

> According to National Grid plc chief executive officer Steve Holliday and others, baseload is "outdated".

https://en.wikipedia.org/wiki/Base_load

[1]: https://www.lazard.com/perspective/levelized-cost-of-energy-...