After many false starts, hydrogen power might now bear fruit

http://large.stanford.edu/courses/2010/ph240/harting1/

Appearances is that losses in transmission lines are a few percent per 1000km. Across the US is about 4000km so you'd lose a little under 20%.

How far is that far?

HVDC only loses ten percent per 3000 km. That is it loses about ten percent transmitting almost from one end of Europe to the other.

Just connect all the national grids together properly, especially in the east-west direction so that areas with sunlight can supply areas that are dark. Also add north-south interconnects to North Africa so that hot dry areas can supply cold wet ones.

See https://en.wikipedia.org/wiki/List_of_HVDC_projects

I really wish that I was wrong instead of just semi-accurate and sloppy.

> Nuclear is not cheap compared to photovoltaics, wind and hydro.

The price of nuclear power is dominated by regulation. Running the power plant is quite cheap. The real cost is satisfying regulation and getting rid of the nuclear waste. If you use new reactor designs it promises to be really cheap. But currently regulation cost is so high that it's not happening any time soon. Similarly, nuclear fusion promises a lot. Maybe one day it will deliver.

My point is that IFF you have dirt cheap nuclear energy, it would be quite appealing to convert it to hydrogen (or Methane/Methanol) and to replace natural gas and oil with it. But since that is not happening, renewables will NOT deliver enough energy to replace gas and oil completely any time soon. We have a factor of 10-100 to scale up for that to happen.

> Since the former two are bursty, overcapacity in them leads to cheap excess energy at times, which needs to be stored.

Wind and solar currently rarely have overcapacity because in many nations mandated by regulations the other sources will have to go offline instead. The problem is that if you really manage to build up wind and hydro to satisfy electricity demand on average the Hydrogen generators will only utilize somewhat in the region of 10% of their design capacity in average. They need to be very cheap to run at a profit for that.

Also, if electricity is really cheap, we have a lot of uses for it. For example heating is ideally done using clean electricity. This substitution frees up a lot oil and gas that you can use instead of Hydrogen.

> Which storage method is the best depends on multiple factors, particularly on the duration of storage, capacity required and frequency of charging/discharging.

> Batteries are great for relatively short term storage, but for long term, seasonal storage, hydrogen and pumped hydro are the options we have. Pumped hydro capacity is limited, and the cost of hydrogen production and storage is coming down. So that's where hydrogen makes sense: Long term, high capacity storage.

True. But if you have enough production capacity, you don't really need storage. You only store it if it is cheaper than simply generating more power when you need it. Instead of generating Hydrogen and storing it you could use a natural gas peaker plant. You have natural gas and storage solutions already available and installed. Hydrogen has to be cheaper than natural gas.

You have some nice academic references while I only have anecdata that may be partially outdated by now. In my past experience Hydrogen and fuel cells have failed to deliver time after time, year after year while Lithium batteries have really taken off.

Look at that figure: https://ars.els-cdn.com/content/image/1-s2.0-S25424351183058...

Currently, Hydrogen is off the charts because it is too expensive but it is projected to come down and dominate the upper end in 30 years while Lithium batteries dominate all the rest. Lithium batteries are here today and the focus is on batteries. Natrium and other battery technologies may be ready by then and drop prices a further factor of 10.

I do not deny that some Hydrogen from electricity makes sense. Especially if you need Hydrogen for your chemical processes. Maybe even for storage of excess electricity (or just adding it to the natural gas instead of storing it). But I don't see Hydrogen for small vehicles anytime soon.

Not necessarily, at least not always. It needs to be used and this can be made possible by expanding the high voltage networks.

This would be especially effective in the east-west direction because then areas with sun could supply areas where it is dark. This reduces the need for storage while also making the system more robust.

If we add more north-south interconnects we can use some of the Scandinavian hydro plants as batteries (I agree that pumped storage can never be as extensive as one would like and is not as easily achieved as some people think) and North Africa for solar power.

What is most lacking is not new technology but political will to interconnect the electrical supply network so that energy can flow more easily from where it is produced to where it is needed.

[0] https://omegataupodcast.net/299-gravity-storage/

How is it better than generating biogas from biomaterial, something we already do at industrial scale? What’s the advantage of biohydrogen over biomethane?

Simply, it is by far the best of all possible aircraft fuels.

Its one major disadvantage for this, as for most uses, is its low mass density: it needs more room than diesel to store enough to be useful. The tanks need to be bigger, and either strong enough to contain high pressure, or well-enough insulated to keep it liquid.

Current aircraft store fuel in wing tanks not roomy enough for hydrogen. The most practical hydrogen-fueled aircraft would probably have a shape more like a lifting body than a submarine with skinny wings sticking out. So for best efficiency, we might need new airframes, but just using hydrogen yields major improvement. To oversimplify, the plane doesn't need to lift so much weight of fuel to cruising altitude, or carry it halfway across the world.

Tankage has improved radically in recent years with the development of aerogels, which make practical carrying liquid hydrogen that need not held be at high pressure, so can be in tanks that conform to an aerodynamically-practical shape. (Other sophisticated storage methods increase weight, so are more practical on the ground.)

Hydrogen is tricky to store for long or in large amounts, so the best way to use it is to produce it on demand where it is needed. A major airport would be a good place to produce it, as it could be piped directly into aircraft and used immediately. All the airport would need is water and power. Power can be collected by wind and solar over a wide area, delivered by transmission lines. The amount of water needed is negligible.

Producing hydrogen would also yield plenty of oxygen, which might just be vented; but by carrying liquid oxygen, aircraft could fly higher, faster, and more efficiently, or at least get to cruising altitude more quickly. As electric power continues to get cheaper, uses for it such as liquifying oxygen along with hydrogen get more attractive.

The first use will be in long-haul craft operating from a few major airports. It is possible that current large aircraft -- 747s, 777s, A380s -- could be converted, by using some of what is now cargo space for tankage, and replacing fuel pipes and pumps and, quite possibly, engines. It would be a big job, made attractive mainly by the extreme cost of qualifying new airframe designs.

The lost cargo space would be made up easily by the much larger weight capacity, as tens of tons less weight of fuel is needed. Cargo aircraft today often fly half-empty so as not to exceed their takeoff weight limit.

In other words, if a refueling station can do solar or wind capture and electrolysis on-site, the economics are better. This would be unlikely for stations in urban or high-density areas, but for rural and suburban locations it might be a win.

Similarly the Tesla plant is doing exactly what it said it was going to do, when it was supposed to be finished, within the budget it had, and AFAIK is making money. You're asserting that it can't scale because it... worked?!

As far as the Pakistani misdesign, yeah, I'm sure that's going to happen too. Nothing works perfectly.

Nonetheless this seems like a pretty oddly constructed list of reasons why solar is "much worse in production". It seems to my eyes like it's doing much better than expected.

With some basic equipment like rolling carts with sprayers and squeegees on extension sticks, how many individual 72-cell sized panels (1.99 x 0.99 meter size) can one person clean in one day? Multiply by probably 4 to 6 full time staff positions.

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', provides power well into the evening, doesn't need more water than they have to clean it, and improves magnificently with high temperatures (the wikipedia article cites the problem of regular 45C days, which are above the 25C optimum temperature for PV panels).

Given all this was known and understood before they broke ground, this sounds like a traditional government project problem -- susceptibility to corruption, vanity, hubris etc.

https://en.wikipedia.org/wiki/Bhadla_Solar_Park

Apparently Bhadla is the world's largest solar park. I wonder if the two countries can co-operate on this (I know relations are mostly hostile currently)

The fact that EV players actually delivered and built charging networks should offer plenty of proof as to which technology is more viable.

It took decades to build out the network of gas stations across countries. The reason it took much less to build out charging networks is because the power grid already existed, we already had 95% of the infrastructure for delivering the "fuel" for EVs.

But hydrogen companies are still talking as if it's super simple to build out a hydrogen infrastructure. Why would that not take decades as well? And that's assuming there was some kind of massive consumer demand for hydrogen vehicles, which there just isn't.

For long distance trips, yes. But unlike with hydrogen vehicles, charging at home is an incredibly simple proposition for BEVs.

https://www.autoblog.com/2020/06/11/catl-million-mile-batter...

2.) Energy required to produce the batteries will eventually shift to zero emission sources.

3.) Materials can be recycled from the battery even after its million+ mile use.

It’s hard to overcome the energy required to produce hydrogen plus the bad efficiency of fuel cells compared to batteries/electric motors.

If this co2 is due to electricity/transportation cost then the problem will solve itself with more electricity from green sources.

He has literally spent the last five years debunking this nonsense. Here's a thread from just 5 hours ago: https://twitter.com/AukeHoekstra/status/1279359481177083904

TL;DR: These comparisons always use too much energy for battery production, too high efficiency for gasoline cars, and fail to take into account that the grid is rapidly decarbonising, even in backwater countries like USA. Your source claims 20 tonnes for battery production, but reality is around 6 tonnes and falling due to grid decarbonising.

Well that's just not at all true. Hydrogen by electrolysis costs <$20/kg. A much more interesting fact about a kg of hydrogen is also that it has very close to the same energy content as a gallon of diesel, and significantly more when used in a fuel cell vs an ICE.

https://www.nrel.gov/docs/fy04osti/36734.pdf

For electricity, as the renewable energy generation capacity will increase, Storage of excess will be essentially required. when in near future we develop viable tech to generate hydrogen from electricity with low or no carbon impact at reasonable efficiency,we can save them in underground reserves(Safest way in my view) and use existing piping infrastructure of natural gas for its transportation. we need to do research and wait for appropriate tech to be available.

Of its nearly half a billion acres of prime cropland, the U.S. uses only 72.1 million acres for corn in an average year. The land used for corn takes up only 16.6% of our prime cropland, and only 7.45% of our total agricultural land.

Even if, for alcohol production, we used only what the USDA considers prime flat cropland, we would still have to produce only 368.5 gallons of alcohol per acre to meet 100% of the demand for transportation fuel at today’s levels. Corn could easily produce this level—and a wide variety of standard crops yield up to triple this.

The key is that you're producing the alcohol as part of an integrated system of production that mimics Nature. You have a farm that requires no inputs (of fertilizer, and in some cases no irrigation) that produces multiple crops per year. ("Syntropic" agriculture, "Permaculture", food forests) You can grow sugar beets, yams, sugar cane, or starchy plants such as potatoes, certain kinds of reeds, tubers, etc. directly for fermentation, or use scrap fruit from the orchards, etc. Literally anything that has starch or sugar can be used as a feedstock. Scrap dough from a (doughnut) bakery.

The leftovers from the fermentation and distillation aren't wasted: you feed them to livestock. Because it's a yeast culture there's more protein in it now than it had before.

So your farm produces fruits and veggies, meat, and alcohol fuel.

(I'm getting all this from http://alcoholcanbeagas.com/sitemap )

If you've got a ready source of hydrogen, say from molten salt oxidation of plastics, which produces "syngas" (a mixture of CO and H2), I think you could run that through water to make CO2 and more H2, feed the CO2 to a greenhouse and collect all the H2 for the reaction you described. Does that make sense?

Saying this ignores basic physics is like saying gasoline engines ignore basic physics. No one is saying that it's free energy. The question is, what is the energy to produce/recycle the alloy? How many miles can you get out of a reasonable supply of the alloy before replacing it? If those numbers are good enough, maybe they'll perform better than battery vehicles. And so I'm asking what's the state of that research.