[thebmax]

These cost comparisons don't take into account reliability. Power is almost useless if it's not reliable. A large part of your monthly bill goes towards reliablility and transport of power, not just the power itself.

A 100% wind or solar grid would require an equal amount of backup gas or coal power in order to provide reliability which essentially doubles these cost estimates. Even now most wind and solar is considered a novelty to most grid operators because you can't take it into account for long term planning. In some cases (like Denmark or Quebec) there exists ample alternatives available for when the wind stops blowing but most jurisdictions don't have this.

Considering how smart people in Silicon Valley are the level of ignorance around renewable energy and the'why don't we all use solar panels' mindset is crazy.

[tokipin]

the obvious solution is batteries, which improve all sources of power generation including traditional ones by serving as support during peak times. in principle you only need <average energy used per house> stored per house during night time, which may be a much lower bar than it sounds. if the utilities serve a role later it may just be them acting as high-volume energy storage facilities, but even that might not really be necessary if individuals can make money by investing in extra batteries.

i think once solar crosses a certain cultural/economic threshold it will just take over everything. it's just way, way too good. there's no other power source that even compares to the potential it already has.

what's interesting is not whether it's going to take over everything, but what kind of economy/world you will have when electricity is orders of magnitude cheaper than it currently is.

[mightybyte]

Batteries aren't the only solution here. Any kind of efficient energy storage will work. For example LightSail Energy has been working on compressed air storage for several years now.

[bryanh]

There is another interesting class of power storage called "pumped-storage hydroelectricity" [1] - for example - there is one in use in Missouri that actually burst in 2005 [2]. Li-ion batteries have a round-trip efficiency of 80-90% - pumped-storage has ~70-80%.

[1] https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...

[2] https://en.wikipedia.org/wiki/Taum_Sauk_Hydroelectric_Power_...

[thebmax]

I'm all for innovation in storage and think there might be a breakthrough at some point. But this goes to the heart of it. Right now a fully renewable grid that matches what we currently have is not financially viable. Not saying it won't become so at some point but it's a high hurdle. All things considered having close to 100% reliable electricity in every home in America for less than ~$100/month is hard to compete with.

[greglindahl]

That totally makes sense -- although renewable energy and energy storage have been making huge strides recently, let's assume that no further improvements will happen.

[thebmax]

Not questioning whether innovation can and will occur. Question is whether the innovations to be developed can compete with what is the present reality which is ~10cents/kWh price that we currently pay for power.

All things considered that is pretty cheap and even a minor improvement on price won't change the sunk costs of current infrastructure. The service of getting electricity is pretty cheap around the country and any replacement will have to be substantially cheaper. 'Better' doesn't count for much here because its just electricity and without government mandates people generally don't really care where it comes from.

Idealists like to say that we 'should' be getting power from somewhere else or in a different way. These idealists tend to ignore the market reality that our current situation isn't that bad for almost everyone.

[pdkl95]

> cheap

This is the big problem that a lot of these discussions tend to ignore. Not only does our market tend to always pick the cheapest options, the real challenge is the developing world that is going to massively increase their power needs in the next few decades. This well have significant benefits for the world in general if we can pull it off. Unfortunately, given the economic realities of these areas that means coal unless we can provide a cheaper option. Unless some breakthrough happens with storage, that means nuclear.

> Idealists

It's easy to be an idealist when your lifestyle already benefits from massive amounts of cheap energy. As Hans Rosling[1] puts it,

    When I lecture to environmentally concerned students, they tell me "No! Everybody
    in the world cannot have cars and washing machines!" ... Then I ask my students,
    "over the last two years, how many of you doesn't use a car," and some of them 
    proudly raise their hands and say, "I don't use a car". Then I put the really tough
    question, "how many of you hand wash your jeans and your bedsheets, and no-one
    raises their hand. Even the hardcore in the green movement use washing machines.
    [...]
    Until they have the same energy consumption per-person, they shouldn't give advice
    to others on what to do and what not to do.
  

[1] https://www.ted.com/talks/hans_rosling_and_the_magic_washing...

[DennisP]

Yes, it makes about as much sense as the assumption by many renewables advocates that nuclear technology can't improve.

[chadgeidel]

I don't disagree with your fundamental premise, but "would require an equal amount of backup power" sounds like hyperbole. I haven't read any proposal for "100% replacement" that doesn't take into account energy storage solutions.

I think it's perfectly reasonable to question those solutions, but an equal amount of traditional power generation as backup seems excessive.

[thebmax]

Case in point is a very cloudy day with no wind. Depending on where it is demand could be very high if it's cold out and heaters are running full blast. You will essentially need a full load supply to come from somewhere or you'll get rolling blackouts. Some regions can compensate with importing or hydro but otherwise you would have to power up the coal and gas. Batteries could maybe work in the future but again this would drastically increase the cost.

[nl]

Flow batteries dramatically change the cost calculations for energy storage, and are here now.

Additionally, most areas are increasingly moving towards decentralised generation which changes the calculations too.

[Klinky]

Scaling down power generation when demand is low is not something nuclear is good at. Battery or energy storage systems that could store excess power from the grid would help any sort of power generation technique become more efficient and reliable.

There is a lot of hand waiving and fudging the numbers when it comes to the cost of nuclear. One-off proprietary designs, using proprietary fuel systems, using proprietary operational methodologies is not cost effective. Economies of scale are not in nuclear's favor, and even "at scale" you're looking at billions of dollars worth of investment before the first watt is produced. The need for large-scale waste transportation, storage and reprocessing is not a solved problem. The Nuclear Solves Everything™ thought process requires a lot of head-in-the-sand thinking.

[mikepurvis]

As a species, we have been generating electricity by nuclear fission for 60 years, and in the process, have produced hundreds of thousands of tons of extraordinarily toxic waste. In all that time, no one has found a final resting place for it. Only one serious DGR has even begun construction— and that's Onkalo (Finland), set to begin receiving waste in 2020, should things go to plan.

All that spent fuel is just sitting on the surface at hundreds of sites worldwide, in pools, dependent on a power supply and ongoing maintenance to the pumps which circulate cooling waters. If those pumps malfunction, or the power supply ceases, the water will boil off, and the wastes will be released into the biosphere. If the US electrical grid ever fails, fossil fuels will have to be trucked to these sites, forever. As long as the grid never fails in the next, oh, few ten to hundred thousand years, we should be all good. How confident are we in the political and economic stability of the US, for millennia to come?

Is it not immensely immoral to be generating power this way, and handing the problem to our distant descendants to deal with? How are they supposed to pay these costs, when we were apparently unable to, despite enjoying the front end benefits of cheap power? Can you imagine if instead of building pyramids in the desert, the ancient Egyptians had left behind a monster that required ongoing babysitting even today, to prevent unleashing catastrophe on the planet?

[DennisP]

The more radioactive something is, the shorter the half-life. High-level nuclear waste from spent fuel rods has three components:

- U-238: less radioactive than uranium ore, makes up most of the waste. Only a problem because of all the other stuff that's mixed in with it.

- Transuranics, mainly plutonium: radioactive for millennia. About 3% of the waste.

- Fission products: the broken-up atoms. The most troublesome are radioactive for decades. About 1% of the waste. Since they have fairly short half-lives, they're the most radioactive.

So it's the fission products which make lots of decay heat and have to be kept cool, but that heat production goes away fairly quickly. It's the transuranics that have to be stored for millennia, but they don't need cooling; since they have long half-lives they don't generate much heat.

However, the U-238 and transuranics could be used as a fuel in more advanced reactors, either fast reactors or molten salt reactors. So actually we only need to store that waste until the more advanced reactors become available.

In the article Thiel advocates pursuing new reactor types, including those that can eliminate long-term waste. If we do that, we'll end up with less long-term waste than we have right now.

[Estragon]

> Scaling down power generation when demand is low is not something nuclear is good at.

Isn't that what control rods do?

[Klinky]

They control the reaction within the reactor, and in newer reactors can be used to regulate load. France & Germany do have a load following system in place for their nuclear reactors. It's not a simple matter of turning off a reactor, as this is a large maintenance task. Various mechanisms and regulations have been developed to handle load following for a Nuclear plant. There are still negatives to doing this, such as reduced efficiency, additional operator training, and additional wear on control, fuel and the plant. Positives likely outweigh the negatives, but the reactor must be designed to do load following and regulations need to be in place to ensure it is done safely. It is another thing to consider when talking about the cost of nuclear.

[olau]

I don't think you framed it correctly. What matters is always matching the consumption curve.

Due to high capital costs, that's really expensive to do with nuclear plants (that's why people talk about baseload, i.e. constant output). So you'd have to solve the same problem in an all-nuclear world - maybe the magnitude would be different, but's essentially the same problem.

You could even say that the 'why don't we all use nuclear power plants' is a bit crazy. :)

[DennisP]

That's why I think nuclear and solar are a good combination: nuclear baseload and solar for extra daytime demand. It won't match consumption perfectly, but it'll do better than either technology alone.

[lyschoening]

A large enough HVDC grid would almost totally eliminate the need for backup power. There's always wind or sun somewhere and HVDC transmission losses are <5% per 1,000mi. It's possible to build a grid where pumped and battery storage alone can smoothen out any fluctuations.

[Terr_]

Then you'd need a global network for sun at night, which has correspondingly greater challenges in terms of coordination and "booting" it back up.