As a side check, there is basically no correlation between VRE combined output at demand. The 5 design basis days are very low output but at fairly average demand. This makes a 'flat' assumption reasonable as a first check.

From a different scenario, but shows the seasonals storage issue: Note the rapid drop off on storage cycles/year by incremental hour of added capacity.

If we instead build 2X as much, then the red line becomes the 'enough' line. Of course this also means on average 50% of the output is curtailed, and the effective cost per unit of useful power is doubled. The regions are shifted as below.

If they were perfectly anticorrelated, all the points would be along the green line. And this would be fine. The points in the yellow region have energy curtailed, and in the red region, there is a shortfall. In purple, the shortfall is more than 50%! (Uri was <30% shortfall!)

Here is an interesting wat to visualize how well Wind and Solar can cover for each other. This is often pointed to as a reason they can be for almost all base supply. Data is For Ontario, and plots the daily average CF of each against each other across 2 years. 🔌💡

I guess 450km is silly?

*Not actually firm. IRENA redefined 'firm' to mean something different than normally meant by firm. The issue here is that the shortfalls represented by the '20%', '10%' or '5%' are massive misses. For example for the Nevada data, the miss would be over 75% of expected output.

And of course wind drops off right as we get to the coldest weather of the system... It had been having a great week prior to that but anouther example with very low capacity value in ELCC defining conditions. 🔌💡

Found in my files from March, 2016. I think it holds up quite well...

For example:

Quick search of some comparables suggest it should be able to get <8500. If that's actual operating that's not great. Maybe lots of ramping?

These look like air cooled condensers, with the big sub atmospheric steam pipe going out to them.

Dry fork looks subcritical

This is what I call the "Default Plan". Build W+S and if cheap enough, some storage in a NG based firm capacity system until "cannibalization" means there isn't enough revenue to build more or system costs rise. It looks to be a very sticky local minima.

And why not just use gas as part of it? Sure, but that's not what some people are demanding we go to. But it would be cheaper. The solid lines are 0 gas and 0 direct emissions. the dashed lines have NG as part of the dispatch. The E ratio is the *clean* power gen to total demand.

Then I did a set of costs based on some assumed costs - a detailed Capex, fixed and variable Opex, model is included, but the LCOE's are shown here for reference, along with the storage - assumed to be a 50% RTE LDES (i.e. Iron-air). The LDES gets unlimited, 'free' charge.

Another way of looking at it, this time in ratio of total nameplate to average energy demand. Note storage is also in relation to average energy demand from load, and load is Ontario's actual mid 2020 to mid 2022 demand, also actual wind and solar CF% with an hourly simulation.

I have been playing around with an interesting concept here - the tradeoff curves of capacity vs storage. First for a completely clean + storage system. This is what we need for Ontario for a no FF system with current demand profile, assuming starting from scratch for clarity. 🔌💡

That being said, is a expansion of wind from ~12GW nameplate to ~30GW nameplate in the next 5 years realistic? Or is a lot of that slower walking baked in already, and if it is the nuclear program could be quite important by the time it shows up if other aspects have stalled.

Overall, the 'go slower' part would result in approx. 0.5-0.7 Gt CO2 based on a 'graphical analysis' (aka eye-balling) the chart. But for approx. $100B+ difference, this implies ~$200/t CO2 as an implicit carbon cost of pursuing this acceleration. Late 2040's on the NPP inclusive is lower emissions

I have seen lots of wishful thinking on dunkelflaute *management*, but I have never seen outright dunkelflaute *denialism* before. Always something new!

Thanks! My point is that the shaded box ends out being a whole lot more complex with cement (vs NG combustion) due to the types of issues highlighted. Low reactivity with NOx is helpful though, hopefully they will still address NOx to reduce that as a pollutant though…

Very much so. For Ontario it looks like this: x.com/Ember421/sta... (I need to port more threads over). This was run with a high C tax to get the line to slope down to the left at all. The '4hr storage' here is $50/kWh TIC. Much above that and it doesn't help much, even with a steap C tax.

Now we add one more twist. This is the ideal site for large industrial dispatchable demand users. For this discussion take H2 production. We can easily use a portion of extraction steam from the turbine to generate or directly supply LP steam to the SOEC.

Now the interesting part begins! Our real challenge is how to deal with extended durations of high load and low VRE (beyond practical batteries). Salt storage will have the same duration issues in the end. So we add a combustion turbine to the site. Liquid fueled would add resiliency.

Now we add a thermal storage. This uses solar salt (Na and K nitrates) and stores it in a hot tank to save for later, after used stores it in a cold tank. There are options to use a single tank, phase change TSS, or packed tanks, etc.

How do we make nuclear the anchor for flexibility and firm capacity? Here is my basic proposal. Let’s start with a 350MW Gen IV reactor. This is basically the Natrium in round numbers, but we could use others, and we can adjust the ratios of turbine / core etc to suit the system. *ANY* ~500C+ works

While I'd love to take that deal on Germany's behalf, they would need more like their entire original fleet to just get rid of lignite, let alone gas as well... But i think we are stuck with that deal anyway as our best case, it's just going to take us as long as it takes us to implement it...