Live data from Hacker News

After many false starts, hydrogen power might now bear fruit

economist.com

231–240 of 343 posts

Re: After many false starts, hydrogen power might now bear fruit

#231

Earlier quoted context omitted.

There's also the work on wireless charging via the roadway, itself. No, it isn't working right now but it's in its infancy. Only the very first prototypes have been rolled out, and they don't wear well, admittedly. Solutions are being worked on. Technology is only limited by your imagination and your ability to problem solve. =)

Capital expenditure, in a system where resources are finite and trade-offs must be made, is a notoriously tricky problem to solve.

A) I love your name

B) That's a fair point, but it is a problem to be solved. Sometimes it's a problem that can't be overcome, and that's the nature of reality. Sometimes reality sucks.

Re: After many false starts, hydrogen power might now bear fruit

#232

Earlier quoted context omitted.

The cost of storing waste is miniscule. Because there's so little of it. The entirety of the US's nuclear waste from electricity generation occupies a volume the footprint of a football field and 10 meters high [1]. The government did build a waste storage facility, which was planned to have cost $150 million [2]. Which is tiny compared to the tens of billions that nuclear plants themselves actually cost. The notion…

> The cost of storing waste is miniscule. Then how come that not a single country has yet developed a method for storing their nuclear waste safely and permanently? From your first link: > The fuel is either enclosed in steel-lined concrete pools of water or in steel and concrete containers, known as dry storage casks. > For the foreseeable future, the fuel can safely stay at these facilities until a permanent dispos…

> > With the zeroing of the budget for Yucca Mountain nuclear waste repository in Nevada, more nuclear waste is being loaded into sealed metal casks filled with inert gas. Many of these casks will be stored in coastal or lakeside regions where a salt air environment exists, and the Massachusetts Institute of Technology is studying how such dry casks perform in salt environments. Some hope that the casks can be used for 100 years, but cracking related to corrosion could occur in 30 years or less.

> In other words the "safe" temporary storage is not really safe.

I think you misunderstood this paragraph. The waste is being stored in these temporary casks because the Yucca Mountain facility's budget was eliminated, and thus temporary storage is the only storage option.

Re: After many false starts, hydrogen power might now bear fruit

#233
post #154

Earlier quoted context omitted.

Check my math: Say a fueling station needs to serve (only) 100 cars per day, providing 50kWh per car. That's 200kW average generation power needed. Ballpark, a 1 m2 solar panel can generate 200kWh/year, or 23W average. (quora answer, 2018). You need .. really? 9100 m2 of area, which is .91 hectare or 2.25 US acres. A 200kW per day (73000kWh/year) wind turbine might stand 25m tall. (uk wind energy report, 2014) Will t…

This is the point (one of the points) that Vaclav Smil makes about renewables: abysmal energy density of production (in Watts/square meter: more like 'intensity' than 'density' to me). The only thing that beats oil is nuclear fission. With everything else, production takes up land that could be used for something else, or isn't being used for something else because it has problems such as distance or inhospitable cli…

concentrating diffuse stuff is the new paradigm. the age of diffusing dense stuff is over.

Re: After many false starts, hydrogen power might now bear fruit

#234
post #223
post #109

Earlier quoted context omitted.

I've read about a couple of solar projects that projected x/kWh and turned out to be much worse in production. Pakistan's big deployment is one example, it was planned to be 100MW but only produced 18MW. Mostly because they didn't factor in the dust that would cover the panels, keeping them clean was very expensive (I'm curious how this applies to other proposed desert deployments). Nor factoring in the typical malai…

> Pakistan's big deployment is one example .. A valid example of what can go wrong when you pick the wrong technology, don't do small scale trials first, and rely on government oversight. (Refer the Background & Operation section of the wikipedia article -- toe-curlingly alarming, yet ultimately unsurprising.) They almost definitely should have pursued concentrated solar thermal. It partly solves the 'storage problem…

Is solar thermal still a going concern? Are new plants still being built?

Re: After many false starts, hydrogen power might now bear fruit

#235
post #24

I've been diving into this literature a bit recently, and it's been mostly encouraging. Affordable clean energy is realistic. Clean energy sources are typically the cheapest sources of energy [0]. The intermittent production issue is solvable: At ~150 $/kWh storage, a combination of storage and renewables is the cheapest energy source 95% of the time [1]. The cost of different energy storage methods is coming down ex…

A little Its a little disheartening that current Lithium-Ion battery storage is at ~$350/kWh and is only projected to hit ~$150/kWh in 2050 [0].

[0] https://www.nrel.gov/docs/fy19osti/73222.pdf

Re: After many false starts, hydrogen power might now bear fruit

#236
post #72

Earlier quoted context omitted.

Electricity has a transmission problem though - there are some parts of the world with lots of clean energy, which we can't fully take advantage of because we can't transport electricity that far. Hydrogen allows us to use that clean energy to power cars in other parts of the world, since you can produce hydrogen in those places and then ship it to places without much clean energy. Also you can presumably stop and st…

Do you know more about hydrogen transport? I heard it is quite more complicated and expensive than LNG (closest equivalent), because hydrogen leaks more easily.

There's also the issue of hydrogen embrittlement of steel, which is probably what causes the leaks I guess?

Re: After many false starts, hydrogen power might now bear fruit

#237
post #223

Earlier quoted context omitted.

> Pakistan's big deployment is one example .. A valid example of what can go wrong when you pick the wrong technology, don't do small scale trials first, and rely on government oversight. (Refer the Background & Operation section of the wikipedia article -- toe-curlingly alarming, yet ultimately unsurprising.) They almost definitely should have pursued concentrated solar thermal. It partly solves the 'storage problem…

Is solar thermal still a going concern? Are new plants still being built?

It seems to be in a lull, but the technology is still maturing. I suspect as the generation + storage costs continue to shift, it'll be adopted more eagerly. PVCs cost reduction has been a boon for that industry, but that tech, of course, ignores the storage problem.

Reading about some of the missteps of CSP, much like the above, they seem to be share similar traits of government mishandling, bureaucracy, dodgy dealings, etc.

EDIT: In any case, a naive interpretation of the Pakistan project cited -- if it truly is getting ~20% of anticipated power, cost per unit is 5x forecast, at which point a CSP would have been better value for money.

Re: After many false starts, hydrogen power might now bear fruit

#238
post #219

Earlier quoted context omitted.

I wonder how much of the 1L evaporates.

During the night and very early morning, probably very little.

Evaporation often happens at night because of the temperature differences.

Re: After many false starts, hydrogen power might now bear fruit

#239

Earlier quoted context omitted.

Nonsense. No one's going to use lithium ion batteries for this use case.

Then what's the alternative? Kinetic storage is geographically limited. Th Sabatier process has end to end efficiency of ~30% not to mention it needs an external source of carbon dioxide. The remaining proposals are at the experimental stage (thermal storage, hydrogen storage).

Cool, I was looking for the efficiency of the Sabatier process. If people are prepared to use electrolosis with a end to end efficiency of ~ 40%. Using the Sabatier process to produce methane begins to look good to me. Just as green as the methane is produced from carbon dioxide and water. And it is much cheaper to produce pipes and tanks for methane and it should be able to be used in all the current natural gas infrastructure (compared to only 20% of the gas in these lines being able to be replaced with hydrogen). It seems to me anywhere where the gas has to be stored or moved the Sabatier process would win economically.

Re: After many false starts, hydrogen power might now bear fruit

#240
post #217

Earlier quoted context omitted.

This is the point (one of the points) that Vaclav Smil makes about renewables: abysmal energy density of production (in Watts/square meter: more like 'intensity' than 'density' to me). The only thing that beats oil is nuclear fission. With everything else, production takes up land that could be used for something else, or isn't being used for something else because it has problems such as distance or inhospitable cli…

What you're calling "energy intensity of production" doesn't look like a very important parameter. There's plenty of unused land that could host solar or wind installations and transporting electricity really is a solved problem. I understand the impulse to defend nuclear power against seemingly irrational criticism, but that shouldn't distract you from the incredible advances that other technologies have been making…

Maybe above 60° latitude Sun energy is hard to harvest, an wind energy could be too unstable. This is where nuclear power would be in place.

Even though not so many people live so far up north, it's a significant part of densely populated Europe.

Post reply on HN