Chernobyl

[Husar]

Not having it tomorrow is the point, we need to wean off fossil fuel now, and solar is anywhere from 40 to 200 years away from being a feasible large scale replacement as Ivanpah illustrates.

Nuclear is here, now, and can keep the world turning that 40-200 years but it is squeamishness that keeps the coal fires burning.

Ivanpah is a single plant in a single location, and the 40 to 200 years sound like a nuclear power fan's pipe dream:
http://ecowatch.com/2015/01/09/count...ewable-energy/
http://qz.com/576437/which-places-ha...newable-power/

Some countries have already reached going 100% renewable, others are working on it. Other plants become less and less important the more is invested into renewables. Of course one question is how much each country is willing to invest or risk.

Sizewell B is turned off for maintenance once every 18 months, before 2006 it could be restarted by Sizewell A and even now it can be started up by any of the other cores on the power grid who had a differing cycle, the non-voltaic solar plants of today cannot alternate operational periods and thus require external power support, of which wind power would be too unreliable to depend on 100% of the time. The only renewable energy that can be harnessed for that duty is water power, and I have noted earlier that it's a good alternative but it can't be used everywhere.

I'm not sure about batteries, the wiki page tells me they require an hours worth of gas power to start so perhaps there isn't an industrial batter large enough to keep them going for that long? The largest industrial battery can power a city, but only for 7 minutes.

Yeah, that was my point, you need another reactor to start up a nuclear reactor and noone would rely on solar or wind alone since that might mean going dark throughout the entire night.

As for batteries, of course you'd bring up the ones with chemical poisons, but there are more ways to store energy:

https://markosun.wordpress.com/2013/...power-station/
http://www.bine.info/en/publications...age-speichern/
http://inhabitat.com/scientists-unve...e-power-plant/

There are also ideas to store heat energy in sand, which can then be used at night to keep up the power and probably to restart the solar plant in the morning, at which point the storages would also be refilled again.

Just like nuclear, you may also want to keep biofuel plants around in case of actual shortages. The CO 2 output would still be nowhere near the one of coal power plants and cars.

Nuclear stations can change their output in terms of what they give to an energy grid, they just cant vary how much fuel is consumed in the process, nuclear materials only having 2 settings: hot and under carbon rod suppression.

http://www.eia.gov/todayinenergy/ima....27/hourly.png

So you'd just turn 30-40GW of NPPs off during the night and restart them the next morning? Keep in mind that shutting one off and starting it again takes several days or even weeks...
NPPs are used for the base load while more flexible ones like coal or gas are used to deal with the peak loads. Renewables can use excess power to load up storages and in the long term there can also be more intelligent grids where renewables can be turned off when not needed, it's certainly faster to turn some mirrors away from the sun than to shut down an NPP.

The costs are one time only, it's not exactly a high maintenance process putting radioactive material in containers and burying them far away from water.

Or they would be one time only if they could get around to digging the holes, as it is only america and Finland have an operating deep rock depository right now.

Also, some countries make each nuclear plant to set aside disposal funds for the day they are decommissioned to pay that cost.

Not every country has easily accessible deep rock storage or a desert where there is no ground water people depend on. In the US people can also light their tap water on fire thanks to responsible business methods. The safety of geological storage is also only given for a certain period of time, which means future generations may have to deal with issues again or may not even know of the dangers lying deep within the planet unless you seriously believe this info will never vanish because it's on the internet now.
From the stanford link from earlier:

Neither onsite storage pools nor dry casks are sustainable high level waste disposal techniques, and because of this many alternative concepts have been studied and proposed. Some alternatives include burial in the sub seabed, launching the waste into outer space, and partitioning and transmutation. [4] Although each of these alternatives has benefits, the consensus is that the best and safest long term option for high level waste disposal is geological isolation. The U.S. Department of Energy has studied a site at Yucca Mountain, Nevada, to determine if it could serve as a geologic repository for spent nuclear fuel and high level radioactive waste. At Yucca Mountain, the repository would have the advantage of being in the desert environment where natural geologic features in tandem with engineered barriers could keep water away from the waste for thousands of years. [4] But, as it currently stands, Yucca Mountain would not be able to store all of the U.S.'s spent fuel and radioactive military waste. In 2006 in the United States, the inventory of spent fuel was approximately 62,000 metric tons, and the projected spent fuel from currently operating nuclear power plants will be at least twice this amount over their lifespans. [6] Just the current amount of spent nuclear fuel would put Yucca Mountain almost to its capacity. This means that either Yucca Mountain will have to be expanded or a second permanent storage facility will be necessary to help store the growing quantities of nuclear waste. Table 1 shows that by 2035, the total amount of nuclear waste in the U.S. is expected to increase to an estimated 104,000 tons. [2] Given the success of dry cask storage and the uncertainties around geologic repositories the Yucca Mountain Repository has been temporarily removed as a solution for high level waste. Even though there are uncertainties involved in geologic isolation, the U.S. will almost certainly need at least one in the future to store high level waste. [7] As of 2010, there is not a single geologic repository in operation anywhere in the world.

Whatever you do with it, it is risky and will stay so for hundreds of thousands of years while, as SFTS said, accidents are still a possibility even with all the safety measures.