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Comment by bullen | Hacker News Reader

The problem with all turbine electric generation is the 30% efficiency of steam turbines. You need to generate 3x the amount of heat, with nuclear you are converting matter into energy; it's boiling the planet.

Solar and wind is a loosing proposition (you put more hydrocarbons into making them than they will generate in their lifetime, and you don't get to pick when they generate), and it can't carry the losses of hydrocarbons.

Hydro is ok, but it's fully installed globally, and again it can never offset the collapse of civilization once hydrocarbons reach peak EROEI: coal peaked in the 70s, oil back in ~2010 and gas is peaking now.

RIP Humans.

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> You need to generate 3x the amount of heat, with nuclear you are converting matter into energy; it's boiling the planet.

This doesn’t make sense to me. Our problems with climate change is not caused by the heat output of the reactors we use. It is because the by-products of combustion increases our atmosphere’s capacity to trap energy from the big fusion reactor in the sky.

My interpretation of your quote was that the boiling wasn’t referring to the heat produced, but instead the idea that mass (our planet) is being converted to energy, reducing the mass of the planet

This may be technically correct, but all the sunlight falling on the ground (which is about 10,000 times our current power usage) is about a kilogram per second under E=mc^2 — it isn't going to be measurable on the timescale of this planet's future existence before being consumed by the sun or ejected from the system due to orbital instabilities, and only even significant compared to the current planetary mass over time periods significantly longer than when all stars in the universe will finish burning all their fuel.

> you put more hydrocarbons into making them than they will generate in their lifetime

They don't get used to make hydrocarbons. The stuff they're made from doesn't have to come from hydrocarbons.

In terms of energy, the same point hasn't been true in a long time (last I heard the time PV systems needed to pay off their own construction energy cost was measured in months, and that was a decade ago).

> and you don't get to pick when they generate

Fortunately storage and transmission lines exist. Fun fact: the material cost of building a global-scale 1Ω circumglobal power grid is a rounding error from the sale price of a year of current global coal mining (assuming almost all of the coal is the low-grade cheap stuff, so less in practice).

Politics will probably prevent that — if you think you can solve the political aspect of this, by all means defeat my cynicism — but technologically it's sound. It is, after all, always sunny somewhere on the planet.

> Hydro is ok, but it's fully installed globally

Also wrong. The unused places may be higher cost or lower quality, but plenty of places do exist.

I think it's important to look at whole lifecycle cost of things.

for example - https://www.nrel.gov/docs/fy21osti/80580.pdf

where natural gas is 400 g co2/kwh, oil is 800 g co2/kwh and all renewables are less than 45 g co2/kwh for total lifecycle cost. wind is 13 g co2/kwh, for cristsake xD

edit: guess my answer is old and it'll get even more efficient over time.

Those numbers might aswell be pulled out of my behind, but atleast they prove how peaked we are.

That said the neodymium mining and the melting involved are things you cannot make easily with electricity.

Also I suspect subventions have found their way into those numbers somehow.

Anyhow we will now use the last scraps of hydrocarbons fighting over those same hydrocarbons. 1st, 2nd and third world war are the same conflict.

Fighting over attention that their parents didn't give them. Love your kids people!

Last but not least, I think the weather might destroy a large proportion of wind, solar and hydro before their lifespan.

> That said the neodymium mining and the melting involved are things you cannot make easily with electricity.

I don't know why you believe this. Doing this kind of thing electrically isn't new — a friend of mine did his PhD in metalysis (and IIRC funded by the company of the same name) about 15 years ago, and that was investigating the details in one specific metal rather than inventing the process itself.

This is going nowhere, eternal growth mentality will get it's backbone broken by nature sooner or later. You will accept that fact too late.

That said, steel f.ex. cannot be made from ore without hydrocarbons at scale. You can recycle it with electric furnaces but at huge cost = no eternal growth.

Academics have never discovered anything useful in their short history on the planet.

Turbines can have higher efficiency at higher steam temperatures.

You have the night and the radiative heat transfer, so you are not boiling the planet.

Hydro ruins ecosystems and accelerates soil depletion by withholding sediment normally deposited by floods.

Lol, nuclear is boiling the planet wasn't on my bingo card

>Solar and wind is a loosing proposition (you put more hydrocarbons into making them than they will generate in their lifetime, and you don't get to pick when they generate), and it can't carry the losses of hydrocarbons.

See here:

https://skeptics.stackexchange.com/questions/17775/how-long-...

>TLDR; Onshore wind produces around 20-80 times as much energy as is required to produce the turbines. Offshore wind about 10-20 times. PV around 10-20 times.

The top answer is 10 years old, there's 10 years of manufacturing and output efficiencies to further improve these ratios.

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