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Cheap, sustainable hydrogen through solar power

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Re: Cheap, sustainable hydrogen through solar power

#101

Post by cduzz »

adrianN wrote: post #85
cduzz wrote: post #68

Earlier quoted context omitted.

You can't operate a car / tractor / hot air balloon with just an efficient house. Also, you can't run your house on an efficient house + solar over the 2-6 months the sun isn't in the right place (in the sky) for very long or when your panels are covered in snow for a week. An efficient house gets you to the table and is a multiplier, but long term energy storage is also really important for lots of people. Hydrogen,…

It's probably more efficient to centralize storing weeks worth of energy.

Many people in rural New England have or wish they had secondary power generation because you need that local energy more often when there are external events that likely also break the grid (big snow storm).

The chain of events is "once in a gazillion century storm wipes power to huge region; millions of households are stuck without power, power company can't go out and fix all the broken things for weeks/months, many people have their houses wrecked by frozen pipes / die from running poorly improvised heat systems"

The round trip energy storage with batteries is pretty good but not terribly cheap at scale. The round trip into hydrogen, theoretically, seems pretty good but the actual "nuance" in the equation is basically a bunch of dragons waiting to eat you and everyone who ever loved you. Anyone selling a "power into hydrogen" thing is probably actually selling a "turn natural gas into hydrogen and sell that hydrogen to hippies" thing.

Maybe if you can figure out how to stick a carbon or two or three onto those hydrogens you'd be in business, but it's hard to get those carbons.

Anyhow, this is a hard problem. People have gotten used to hydrocarbons which are basically magic given their stability and energy density.

Re: Cheap, sustainable hydrogen through solar power

#102

Post by pstuart »

conradev wrote: post #81
fbdab103 wrote: post #19

I am waiting for the day when there is an affordable ( Is anything like that on the horizon? Or do all of these liquid fuel synthesis options require industrial pressures/volumes/input electricity so as to forever be out of reach from residential synthesis?

It’s just a matter of cost. Cost savings will come from improved efficiency and manufacturing innovation. You can make a lot of electrofuels in a distributed way: Hydrogen (Water + Electricity): There are many containerized electrolysers Ammonia (Air + Electricity): https://www.nitricity.co/ Methane (Air + Electricity): https://terraformindustries.com/

Looks promising!

Re: Cheap, sustainable hydrogen through solar power

#103

Post by rexspex »

I am doubtful that this scales. Main concern is the cost in materials, fuel, and electricity in manufacturing large lenses. Sure, it seems that there are large increases in efficiency when generating hydrogen.. But not really once you take into account the cost of generating the infrared.

Re: Cheap, sustainable hydrogen through solar power

#104

Post by solraph »

PaulDavisThe1st wrote: post #89
chiefalchemist wrote: post #86

Earlier quoted context omitted.

Perhaps. But then that means the power lines need to be maintained, even when not in use. I'm not sure what the amount is, but it's probably not insignificant.

I live in New Mexico with a 6.7kW array. My house is heated with air source heat pumps. In the summer, we generate 3x the electricity we need. In the winter, we generate 1/3x of the electricity we need. Last year we generated 91% of all our electricity, the year before 93%. We would need a gigantic store for heating our house, because for 4-5 months a year, we are generating less electricity than we need. Something o…

15MWh of storage seems very high? I appreciate I don't know your raw numbers of production and consumption, but don't you still produce some power during the winter? ie; you would only need to cover your shortfall.

For context, I live in the cloudy-ish south of Australia, and have similar problems with our solar power in winter. However, we still produce reasonable amounts of power through the day, and our total winter shortfall is only about 500 kwh, once offset against the daily production.

So for us, 500kwh -> 2080.8 MJ -> 462.4 litres of storage required (assuming 4.5 MJ / litre and ignoring round trip losses), which seems an entirely reasonable for local storage, safety aspects not withstanding.

Re: Cheap, sustainable hydrogen through solar power

#105

Post by EugeneOZ »

EugeneOZ wrote: post #51

> As humanity tries to reduce its carbon emissions It's time to change this stereotype. Humanity tries to reduce its greenhouse gases emissions, and CO2 is not the biggest problem.

Dear downvoters, read the facts and numbers: https://www.unep.org/news-and-stories/story/methane-emission...

Re: Cheap, sustainable hydrogen through solar power

#106

Post by yummypaint »

cduzz wrote: post #101
adrianN wrote: post #85

Earlier quoted context omitted.

It's probably more efficient to centralize storing weeks worth of energy.

Many people in rural New England have or wish they had secondary power generation because you need that local energy more often when there are external events that likely also break the grid (big snow storm). The chain of events is "once in a gazillion century storm wipes power to huge region; millions of households are stuck without power, power company can't go out and fix all the broken things for weeks/months, ma…

If the concern is gaurenteeing that power is always available, the answer is a backup generator. It won't consume fossil fuels unless it's actively in use (very rarely). The carbon taken out of the atmosphere by having an efficient house with solar and grid connection during the rest of the year will more than offset the generator.

I contend that the unsexy combination of solar, a bidirectional grid connection, and an emergency diesel generator is more efficient and environmentally friendly than any existing system involving hydrogen or batteries.

Re: Cheap, sustainable hydrogen through solar power

#107

Post by viewtransform »

pkphilip wrote: post #63
miahi wrote: post #29

Earlier quoted context omitted.

Hydrogen storage is not something that you really want to do at home, especially in "saving up" quantities. It is quite happy to explode, you need tremendous pressures and low temperatures for efficient storage, and also hard to contain (many "normal" materials are permeable to hydrogen). [1] [1] https://en.wikipedia.org/wiki/Hydrogen_safety

There are ways of storing hydrogen in metal hydrides at room temperature and pressure. This makes a LOT of sense for people who may want to have an option of buying stored energy - such as those who live in apartments without access to the terraces where solar panels can be deployed. If these metal hydride storage is used similar to how changeable batteries are used, it is conceivable that you could drive up to a pla…

Is the watts/kg for this electicity ->hydrogen+metal hydride storage solution better than an electicity -> lithium-ion battery solution ?

Re: Cheap, sustainable hydrogen through solar power

#108

Post by _hypx »

theshrike79 wrote: post #64
_hypx wrote: post #55

Earlier quoted context omitted.

Fuel cell vehicles also use electric motors. They will not lose to combustion engines on efficiency. You seem to contradict yourself on how you think hydrogen vehicles work.

Fuel cell vehicles sill need hydrogen to generate the electricity. Hyrdogen has about 80% losses from electricity to wheels. When 55kWh of electricity is used to generate hydrogen and that is used in a Toyota Mirai to move the car, only 11kWh ends up at the wheels. If you do that same with a Hyundai Ioniq 5, all 55kWh (minus some transfer losses) get to the wheels.

Those are purely made up numbers. A fuel cell will easily be more efficient than an internal combustion powered car. Also, a battery is not 100% efficient, nor is charging an EV 100% efficient.

Re: Cheap, sustainable hydrogen through solar power

#109

Post by Schroedingersat »

philipkglass wrote: post #32
Schroedingersat wrote: post #27

Earlier quoted context omitted.

Most rare elements are extracted primarily as side products. Scaling production directly is very difficult without demand for the co-occuring minerals.

Gallium is a side product of producing aluminum and zinc. Most processing of gallium-bearing raw materials for aluminum and zinc production does not currently incorporate any gallium separation stages. Current rates of gallium production can increase 5-fold without increasing rates of aluminum/zinc production or improving extraction techniques; current extraction techniques would just need to be deployed more widely.…

Love the way you just slid right past the indium there which is the one that actually matters.

Re: Cheap, sustainable hydrogen through solar power

#110

Post by Schroedingersat »

defrost wrote: post #33
Schroedingersat wrote: post #27

Earlier quoted context omitted.

Most rare elements are extracted primarily as side products. Scaling production directly is very difficult without demand for the co-occuring minerals.

Fortunately Gallium comes primarily from either bauxite (aluminum) or zinc deposits in more or less the same amount (~50ppm). Ergo there's 50 tonnes of gallium per million tonne of bauxite, or 5,000 tonne of gallium in the annual 102 million tonne per annum bauxite production of Australia (alone). These 5,000 tonne exceeds the current global demand for raw pure gallium by a factor of ten .. so it's not the demand for…

Yes. I definitely meant the gallium alone and was not including the indium.
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