Hacker News new | past | comments | ask | show | jobs | submit login

The quantity of easily extractable energy available from nuclear fuel dwarfs anything else known. A single nuclear fuel pellet contains the same amount of energy as a ton of coal. 20 tons if all of the energy is extracted.

How many tons of easily exploitable coal/ng/etc exist in the world? Nevermind easily exploitable: how much energy exists, period, in fossil deposits?

It's dwarfed by nuclear fuel. 1 cm3 to 20 tons.

Energy density also makes things easier. You can transport a year's worth of energy on one train. You can ship it to remote areas. To get a lot of energy out of the ground, you don't need a huge extraction process like fracking or strip mining.




I'm not being obtuse - I still don't understand why this is important. Is 'ability to transport a lot of energy on a train' really key? Renewables have a completely different model for how they are distributed and how their supply is constrained.


There are two "renewable" sources of power: solar (wind and hydro are there with solar, but their energy potential is smaller and their downsides larger) and nuclear*.

Solar makes a lot of energy, but:

- you need a lot of land to make energy

- energy generation scales poorly with materials required

- you lose efficiency because you have to transport the power from the optimal place to every other place

By contrast, nuclear can be built anywhere regardless of climate (greatly reducing transmission loss), fuel is fairly widely distributed (i.e. every big political bloc has a good source of uranium), it provides continuous power, and material costs are low to build massive plants. And there is a lot of energy stored in the world's nuclear reserve. Way more energy than is stored in coal/ng/oil. Because of the energy density of nuclear fuel, if you add a little bit more material input, you get a lot more power. Not true with solar or any other source.

You can't run an entire advanced economy on solar, or even majority on solar. By contrast, you can have a 100% zero emissions economy run entirely on nuclear. My main point would be that if we want to continue to grow technologically, energy production must be centered on nuclear, with enhancements to efficiency provided by solar energy. Energy is the ultimate constraint on human development.

That's not what we have, though. Most people think that we can completely de-carbonize using solar energy which is false. Running an entire grid on batteries at night is a pipe dream -- the US grid has 3 seconds of energy storage total. By contrast, the technology for a completely de-carbonized modern economy exists right now with nuclear.

* I consider nuclear "renewable" because there's so much energy that in the short term, it may as well be.


> You can't run an entire advanced economy on solar, or even majority on solar.

Sure you can. Defend this claim.


If you want power at night, what do you do? If it's cloudier one day than another, what do you do? You need baseline production to flatten the peaks and valleys.

If you want to run on solar, you need to provision far more supply of energy than demand (and use a ton of material/land to do so), and then melt rocks or something when there's too much supply. Or build a continental power distribution grid that wastes all the energy you've made to get a trickle of power from over-provisioned areas to under-provisioned ones. Or, you can store it all in batteries. OK? What are losses? How many batteries do we need to build for grid-wide ~12h of storage? The answer is, a lot. What are the costs of mining, building, installing, replacing all those batteries?

The key thing I'm driving at is efficiency. Losses. The efficiency in batteries is not good. The efficiency in moving energy 1000's of miles is not good. Those are required for a majority solar grid.

The conversation here is not about whether it's possible, but whether it is efficient. It is possible after all to power the whole grid with coal.


None of that argument justifies your claim. Yes, storage is needed. No, that doesn't mean solar cannot power civilzation. Simply raising questions doesn't prove your point. It's up to you to show that all the various storage technologies, alone or combination, along with transmission and dispatchable demand, cannot do the job.

No, it IS about whether it's possible. You didn't claim it wasn't "efficient", you claimed it wasn't possible. "Can't." I'm not sure why efficiency matters -- is agriculture impossible because its average efficiency at converting sunlight to food energy is less than 1%?




Consider applying for YC's Spring batch! Applications are open till Feb 11.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: