Green energy is in the costs of 8 cents/Wh. Coal is more expansive as gas always was. Only nuclear is calculated with 2 cents/Wh ignoring the costs of the nuclear waste as this paid for by taxes in addition.
"In Deutschland zum Beispiel geht etwa die Hälfte des gesamten Wasserverbrauchs für das Kühlen der Atom-, Kohle- und Gaskraftwerke drauf [...]"
https://www.heise.de/tp/features/Krisenstab-eingesetzt-Atomd...
https://www.hubertus-zdebel.de/atommuell-kommt-teuer-offizie...
Because as we do not have a final deposit for nuclear waste there are no costs for it. There are only models with suggested costs. But all of this is not priced into it.
A German paper produced by the independent "Wissenschaftlicher Dienst des Bundestages": https://www.bundestag.de/resource/blob/887090/1867659c1d4edc...
For example the total lifetime costs of Onkalo (Finlands spent nuclear fuel storage site) is estimated to be 3.5 billion.
Lets take the new OL3 reactor as a example. It produces at 1600MW which comes to around 14 million MWh in a year so 14 billion kWh per of electricity produced yearly (slightly less in reality with downtimes for refueling and maintenance). That would mean that if storing the spent fuel would actually cost 38c/kWh just OL3 would generate ~5.3 billion euros worth of fuel storage costs per year which is more then Onkalo lifetime total costs. And OL3 has a planned operational life of 60 years.
And Onkalo is supposed to store all of Finlands already produced spent nuclear fuel and the fuel produced in the next 100 years.
Even if you add dismantling costs of the plants at the end of their lifetime there is no way to get to such crazy numbers even if it costs 2 or 3 billion euros per reactor to rid of. Lets say with 60 year lifetime of OL3 you get around 840 billion kWh produced and decomissions costs 5 billion it would be ~0,6c/kWh of cost. Yes it costs but not tens of cents. For the older plants that produce less it would be around 1c/kWh.
In Finland they started to collect money into a fund for decomissioning and spent fuel storage in the 80s and it currently has a bit over 20 billion euros in assets (the fund invests the money on markets so it fluctuates obviously). So basically they try to do their best to estimate how much money they need to save and collect it during the lifetime. For now it looks like the amount has been roughly correct. And still the for profit companies keep investing into new nuclear plants with this cost already in the price so it doesn't seem to be too much.
And there’s a bit of unused space in Finland :)
The facility (Onkalo) does not need any maintenance once it has been filled up and closed as you just fill the whole thing making access to it very very hard as it is 520m under ground so a couple kilometers of tunnel to dig through to get to it. (clay sediment at the bottom where the vessels are and concrete for the pathway up)
As I said the 3.5 billion is the projected total lifetime costs of the permanent storage site Onkalo. So that is the total cost (to the best of our ability to estimate for it)
One of the most used metrics is the so called Levelized Cost of Electricity (LCOE). The LCOE includes investment, maintenance and operation, fuel and "carbon" costs, as well as waste costs. However, the waste costs are only calculated for the years of operation, so it's not really a great number to look at in terms of actual total cost.
Regardless, the LCOE the German federal government uses is 4-8 cents/kWh for onshore wind, 2-6 for photovoltaic, 14-19 for nuclear.
The (former) nuclear plant operators in Germany are required to pay into a fund that is meant to be used for covering the costs of decommissioning and disposal of the plants, as well as long term storage (except not everything is covered[0]). This is not included in the LCOE. Anyway, operators are required to pay a total of 47 billion EUR into that fund[1].
The old East German plants that got shut down right after the German reunification and are in the process of slowly being deconstructed and disposed of[2] are now estimated to cost 3-7 billion EUR a piece for full disposal (but not storage). If that's any indication, even when considering "lessons learned" will lower costs for future decommissioning and deconstruction, those 47 billion EUR is very unlikely to cover the eventual costs of deconstructing those 20-odd decommissioned German nuclear facilities and store spent fuel and contaminated materials for the first few decades. Some economists from the DIW (the private German Institute of Economic Research, not exactly tree huggers) calculated the eventual cost until 2100 will be closer to 169 billion EUR in 2019s money.
There are some eco lobbying organizations - obviously not without their own bias - that make claims such as "the true cost of nuclear is 42.2 cents/kWh while wind is 8.1 cents/kWH"[3]. I have previously looked through their numbers and argument in more detail, and it sounded mostly very sound to me, however I am a layperson.
Regardless, the fact is: we do not actually know yet the total cost of nuclear power.
[0] E.g. German tax payers have spent 1.5 billion EUR just on exploring potential long term storage sites so far. Just exploring.
[1] This is still litigated a bit, as the German legislature only really had the great idea to make a law about that in 2016. That's another reason nobody historically included it or now includes it in the LCOE.
[2] E.g. the old Greifswald plant. When it operated, it employed 10,000 people. Now 32 years after it officially ceased operation in 1990, it still employs around 1,000 people. Full deconstruction and disposal is now expected to happen by 2028 and will eventually have accumulated costs of a total of 6.5 billion EUR according to the company in charge of the disposal. Not including long term storage costs. Since the operator of those things used to the East Germany, it's now the Federal Republic of Germany's full responsibility to pay for that.
[3] https://www.bund-sh.de/energie/atomkraft/hintergrund/die-wah...