Progress to hydrogen fuel produced from sunlight

[endicom]

Next Big Future
Brian Wang
Apr. 25, 2018

A team of Renewable Energy experts from the University of Exeter has pioneered a new technique to produce hydrogen from sunlight to create a clean, cheap and widely-available fuel.

The team developed an innovative method to split water into its constituent parts – hydrogen and oxygen – using sunlight. The hydrogen can then be used as a fuel, with the potential to power everyday items such as homes and vehicles.

Crucially, hydrogen fuel that can be created through this synthetic photosynthesis method would not only severely reduce carbon emissions, but would also create a virtually limitless energy source.

More... https://www.nextbigfuture.com/2018/04/progress-to-hydrogen-fuel-produced-from-sunlight.html#more-144359

[Oceander]

But will it scale to commercial quantities?

[Joe Wooten]

But will it scale to commercial quantities?

No, as it does not solve the BIG problem with electrolysis of water to make hydrogen gas - the fact that it takes more energy (by a wide margin) to make hydrogen than you get out of it as a fuel.

[endicom]

But will it scale to commercial quantities?

To be determined.

The author, Brian Wang, chose to title this as Progress to hydrogen fuel produced from sunlight. I think that states his opinion. Nonetheless, progress is progress.

[endicom]

No, as it does not solve the BIG problem with electrolysis of water to make hydrogen gas - the fact that it takes more energy (by a wide margin) to make hydrogen than you get out of it as a fuel.

The production energy here is sunlight.

[Joe Wooten]

The production energy here is sunlight.

It does not matter, it still is not free of cost. It still is an inefficient method of making transportation fuel. It takes more power in electricity to produce the hydrogen than you get out of the vehicle you fuel it with. To be able to compete with gasoline/diesel vehicles will require a massive taxpayer subsidy not only to make the hydrogen, but also to build the infrastructure to distribute it.

Solar PV electricity is even more expensive than electricity produced by gas/coal/nuclear, so this is even more of a money loser. There was a proposal many years ago to build a 4 unit nuke to do nothing but make hydrogen fuel. The cost of the hydrogen was several times higher than the cost of gasoline, which in Illinois was approaching $4/gallon at that time. The feds refused to subsidize it and the project died.

[IsailedawayfromFR]

God gave us cheap and plentiful fossil fuels to supply us with energy to lift us to higher standards of living.

I really do not understand why people are feverishly trying to stop their usage and go hog-wild with more expensive and, in the case of hydrogen, unproven and dangerously combustive energy.

Hydrocarbons are proven to be available and used widely to supply our needs, with limited downsides.  As far as producing CO2 as a byproduct, this is proven to be beneficial for plant life growth and unproven for any detriment to the climate of the earth.

[endicom]

It takes more power in electricity to produce the hydrogen than you get out of the vehicle you fuel it with.

It takes more energy to produce electricity than is in the electricity produced.

It takes more energy to produce gasoline than is in the gasoline produced.

 

[thackney]

It takes more energy to produce electricity than is in the electricity produced.

True.  But to make the hydrogen, it first has to produce electricity, so their is a much greater inefficiency.

It takes more energy to produce gasoline than is in the gasoline produced.

False, because the original feedstock (crude oil) contains significant energy with minimal energy used to harvest or mine (drilling).

[endicom]

False, because the original feedstock (crude oil) contains significant energy with minimal energy used to harvest or mine (drilling).

Crude oil is not gasoline.

Exploration, drilling, transporting, refining and again transporting, all expend energy.

[Elderberry]

Do Gasoline Based Cars Really Use More Electricity than Electric Vehicles Do?

Business Insider published an interview today with Tesla founder Elon Musk in which Musk makes a striking claim: “You have enough electricity to power all the cars in the country if you stop refining gasoline,” he asserts. “You take an average of 5 kilowatt hours to refine [one gallon of] gasoline, something like the [Tesla] Model S can go 20 miles on 5 kilowatt hours.”

It’s a claim that I’ve seen pop up frequently in recent weeks, often framed as an assertion that electric cars use less electricity than normal ones. There’s only one problem: It’s not true.

The math behind the claim is simple. Refinery efficiency is about 90 percent and the energy content of a gallon of gasoline is about 132,000 Btu. Put that together and you have about 13,000 Btu of energy cost per gallon of gasoline produced, which is equivalent in energy terms to 4 kilowatt hours. (The 6 kilowatt hour claim is based on outdated efficiency figures.)

But this is flawed in two big ways. The first is that most of the energy used by refineries doesn’t come from electricity; only about 15 percent of it does. That cuts the electricity-used figure down to about 0.6 kilowatt hours. The second is that conversion of fuel to electricity is pretty inefficient. A process loss of energy equivalent to 0.6 kilowatt hours translates to an actual electricity loss of around 0.2 kilowatt hours.

This is consistent with refinery data. The Department of Energy estimates that refiners used 47 TWh of electricity in 2001 to produce refined products from 5.3 billion barrels of oil. Assuming  that you get 42 gallons of refined products from each barrel of oil, this works out to about 0.2 kilowatt hours of electricity used for each gallon of gasoline produced.

https://www.cfr.org/blog/do-gasoline-based-cars-really-use-more-electricity-electric-vehicles-do

[thackney]

Crude oil is not gasoline.

Exploration, drilling, transporting, refining and again transporting, all expend energy.

And all that energy combined doesn't come close to the energy contained in the final products of the transportation fuel.

It is like mining coal.  The products contain far more energy than was used producing them, start to finish.

[Restored]

Ya'll missed the point.
You can use solar/wind/thermal/hydro to produce the electricity to create the hydrogen. Iceland generates completely clean energy. They could create the hydrogen without needing fossil fuels. I think their clean energy generation is pretty endless.
Oh, the humanity....

[thackney]

Ya'll missed the point.
You can use solar/wind/thermal/hydro to produce the electricity to create the hydrogen.

And still, there are significant losses in using hydrogen as compared to simply using the electricity in the first place.  Hydrogen is a horrible fuel, unless you are only concerned with mass to energy ratios, such as a rocket to outer space.  It loses in all other comparisons.

Iceland generates completely clean energy. They could create the hydrogen without needing fossil fuels. I think their clean energy generation is pretty endless. Oh, the humanity....

All their electricity is from "clean" due to their immense hydropower resources and smaller geothermal.  They also use a lot of heat directly from geothermal.  They also are able to accomplish this due to the relatively small economy.

They don't run on only electric or hydrogen cars because of the immense cost that would actually require.  That clean energy may not require fossil fuels, but it isn't free.

[Oceander]

No, as it does not solve the BIG problem with electrolysis of water to make hydrogen gas - the fact that it takes more energy (by a wide margin) to make hydrogen than you get out of it as a fuel.

Production (as opposed to exploitation) of all fuels is a net energy-losing endeavor.  The Nazi’s pursuit of synthetic fuels being a case in point.  Fossil fuels appear to be cost-effective in this scenario simply because the work of making the fuels - putting the energy content in - has already been done. 

If hydrogen fuel can be produced solely through the use of solar energy, then the question is whether the cost of the equipment needed to capture and apply that solar energy, and to capture and store the resulting hydrogen fuel, is cost-effective compared to the costs to discover, exploit, and store fossil fuels. 

[thackney]

If hydrogen fuel can be produced solely through the use of solar energy, then the question is whether the cost of the equipment needed to capture and apply that solar energy, and to capture and store the resulting hydrogen fuel, is cost-effective compared to the costs to discover, exploit, and store fossil fuels.

These process have an easier comparison.  Unlike steam-reforming of Natural Gas, the use of solar or wind or hydro or geothermal to make hydrogen first requires making electricity.  The inefficiencies of moving from electric power to hydrogen in a usable form are immense compared to simply staying with electricity at that point and storing in batteries.

We use hydrogen in modern refineries to reduce the sulfur content of transportation fuels.  It takes a lot of energy to compress it due to the low specific gravity that creates a lot of waste heat.  It takes expensive special metal alloys and more expensive finishing on the piping and parts that handle it.  It is a not a good choice for fuel, it is very inefficient to use.

[Oceander]

These process have an easier comparison.  Unlike steam-reforming of Natural Gas, the use of solar or wind or hydro or geothermal to make hydrogen first requires making electricity.  The inefficiencies of moving from electric power to hydrogen in a usable form are immense compared to simply staying with electricity at that point and storing in batteries.

We use hydrogen in modern refineries to reduce the sulfur content of transportation fuels.  It takes a lot of energy to compress it due to the low specific gravity that creates a lot of waste heat.  It takes expensive special metal alloys and more expensive finishing on the piping and parts that handle it.  It is a not a good choice for fuel, it is very inefficient to use.

Exactly.  That was my point.  The equipment needed to get from hydrogen in the wild to a useful fuel is at present more expensive than other fuel types. 

[Joe Wooten]

Do Gasoline Based Cars Really Use More Electricity than Electric Vehicles Do?

Business Insider published an interview today with Tesla founder Elon Musk in which Musk makes a striking claim: “You have enough electricity to power all the cars in the country if you stop refining gasoline,” he asserts. “You take an average of 5 kilowatt hours to refine [one gallon of] gasoline, something like the [Tesla] Model S can go 20 miles on 5 kilowatt hours.”

It’s a claim that I’ve seen pop up frequently in recent weeks, often framed as an assertion that electric cars use less electricity than normal ones. There’s only one problem: It’s not true.

The math behind the claim is simple. Refinery efficiency is about 90 percent and the energy content of a gallon of gasoline is about 132,000 Btu. Put that together and you have about 13,000 Btu of energy cost per gallon of gasoline produced, which is equivalent in energy terms to 4 kilowatt hours. (The 6 kilowatt hour claim is based on outdated efficiency figures.)

But this is flawed in two big ways. The first is that most of the energy used by refineries doesn’t come from electricity; only about 15 percent of it does. That cuts the electricity-used figure down to about 0.6 kilowatt hours. The second is that conversion of fuel to electricity is pretty inefficient. A process loss of energy equivalent to 0.6 kilowatt hours translates to an actual electricity loss of around 0.2 kilowatt hours.

This is consistent with refinery data. The Department of Energy estimates that refiners used 47 TWh of electricity in 2001 to produce refined products from 5.3 billion barrels of oil. Assuming  that you get 42 gallons of refined products from each barrel of oil, this works out to about 0.2 kilowatt hours of electricity used for each gallon of gasoline produced.

https://www.cfr.org/blog/do-gasoline-based-cars-really-use-more-electricity-electric-vehicles-do

That data is for ALL refined products, not just gasoline/diesel. Each step of extracting different products from a barrel of oil takes different levels of energy to get them out. Besides, I'd look skeptically at any claims Musk makes defending his electric cars. He's been known to exaggerate good things and skip over bad details.....

[Joe Wooten]

And still, there are significant losses in using hydrogen as compared to simply using the electricity in the first place.  Hydrogen is a horrible fuel, unless you are only concerned with mass to energy ratios, such as a rocket to outer space.  It loses in all other comparisons.

All their electricity is from "clean" due to their immense hydropower resources and smaller geothermal.  They also use a lot of heat directly from geothermal.  They also are able to accomplish this due to the relatively small economy.

They don't run on only electric or hydrogen cars because of the immense cost that would actually require.  That clean energy may not require fossil fuels, but it isn't free.

Geothermal plants are not clean, have huge capital costs on a par with nuclear, and have higher maintenance costs than coal plants. Geothermal plant heat exchangers in particular have limited lifetimes due to the corrosive nature of the hot water they take from the ground. it is chock full of minerals, salts and sulfides.

[Joe Wooten]

Production (as opposed to exploitation) of all fuels is a net energy-losing endeavor.  The Nazi’s pursuit of synthetic fuels being a case in point.  Fossil fuels appear to be cost-effective in this scenario simply because the work of making the fuels - putting the energy content in - has already been done. 

If hydrogen fuel can be produced solely through the use of solar energy, then the question is whether the cost of the equipment needed to capture and apply that solar energy, and to capture and store the resulting hydrogen fuel, is cost-effective compared to the costs to discover, exploit, and store fossil fuels.

The infrastructure to distribute the hydrogen would cost a major fortune, and the range of the vehicles would be limited by the low density of the hydrogen, which would require very high pressures to store a usable amount, which means very heavy thick wall pressure vessels, which adds parasite weight to the vehicle, reducing its performance. It would be even more if you went cryogenic, which would add cooling equipment that adds more weight and takes power to run continuously.

The capital cost of a refinery would be dwarfed by the costs of a solar powered hydrogen plant that produced the equivalent BTU of a typical refinery, plus you would not have the other money makers in the petrochemicals that a refinery has. The amount of energy used by a refinery is dwarfed by the energy it produces for sale.

[endicom]

Production (as opposed to exploitation) of all fuels is a net energy-losing endeavor.  The Nazi’s pursuit of synthetic fuels being a case in point.  Fossil fuels appear to be cost-effective in this scenario simply because the work of making the fuels - putting the energy content in - has already been done. 

If hydrogen fuel can be produced solely through the use of solar energy, then the question is whether the cost of the equipment needed to capture and apply that solar energy, and to capture and store the resulting hydrogen fuel, is cost-effective compared to the costs to discover, exploit, and store fossil fuels.

You're almost there.

What matters is the cost and not the amount of energy used to produce an energy product.

[Oceander]

You're almost there.

What matters is the cost and not the amount of energy used to produce an energy product.

I already got there and sent home post-cards.  That was my point. 

[Joe Wooten]

Do Gasoline Based Cars Really Use More Electricity than Electric Vehicles Do?

Business Insider published an interview today with Tesla founder Elon Musk in which Musk makes a striking claim: “You have enough electricity to power all the cars in the country if you stop refining gasoline,” he asserts. “You take an average of 5 kilowatt hours to refine [one gallon of] gasoline, something like the [Tesla] Model S can go 20 miles on 5 kilowatt hours.”

It’s a claim that I’ve seen pop up frequently in recent weeks, often framed as an assertion that electric cars use less electricity than normal ones. There’s only one problem: It’s not true.

The math behind the claim is simple. Refinery efficiency is about 90 percent and the energy content of a gallon of gasoline is about 132,000 Btu. Put that together and you have about 13,000 Btu of energy cost per gallon of gasoline produced, which is equivalent in energy terms to 4 kilowatt hours. (The 6 kilowatt hour claim is based on outdated efficiency figures.)

But this is flawed in two big ways. The first is that most of the energy used by refineries doesn’t come from electricity; only about 15 percent of it does. That cuts the electricity-used figure down to about 0.6 kilowatt hours. The second is that conversion of fuel to electricity is pretty inefficient. A process loss of energy equivalent to 0.6 kilowatt hours translates to an actual electricity loss of around 0.2 kilowatt hours.

This is consistent with refinery data. The Department of Energy estimates that refiners used 47 TWh of electricity in 2001 to produce refined products from 5.3 billion barrels of oil. Assuming  that you get 42 gallons of refined products from each barrel of oil, this works out to about 0.2 kilowatt hours of electricity used for each gallon of gasoline produced.

https://www.cfr.org/blog/do-gasoline-based-cars-really-use-more-electricity-electric-vehicles-do

So a refinery uses 0.2 kwhr/gallon to produce, each gallon will produce 33.4 kwhr. That is a very good ratio, 167-1, whereas hydrogen is a negative.