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Cairn Lodge Services “Leads the Charge” with the UK’s first Public Hydrogen Powered Electric Car Charging Points
https://www.geopura.com/in-action/cairn ... he-charge/

Seems like a good step forward.....

Interesting that they're not also offering to supply the hydrogen as a fuel....
Guess the lack of demand for hydrogen vehicles made it uneconomic....?

The negative EROEI in hydrogen might also have something to do with it.

Hydrogen is not the solution for general car transport. It has been obvious for decades that they could not compete with batteries. I watched a tube video this morning about a hydrogen filling station in Finland which had stopped operating as uneconomic. It cost 2m Euros to build. There was an abandoned hydrogen car there, waiting for fuel which would never come.

I can only see hydrogen being a suitable fuel source if batteries become less economic or the raw materials become unavailable, or if there is a requirement for propulsion in a remote inaccessible place where batteries are not available, or if 'refuelling' times of less than several minutes are required and long ranges are required. Otherwise the EROEI of hydrogen goes against it.

Just one other thought. Production of hydrogen can in theory be done at home or outside of government control and taxation. Electricity charging can also be considered as well but maybe the powers that be don't like the thought of people filling up their own cars with untaxed hydrogen?

In the summer I fill up my battery with zero taxation, I get about four months entirely tax free transport (if you ignore overheads like MOT charges and tax on legally required insurance and new tyres, etc)

BritDownUnder wrote: ↑01 Jan 2024, 21:25 I can only see hydrogen being a suitable fuel source if batteries become less economic or the raw materials become unavailable, or if there is a requirement for propulsion in a remote inaccessible place where batteries are not available, or if 'refuelling' times of less than several minutes are required and long ranges are required. Otherwise the EROEI of hydrogen goes against it.

Just one other thought. Production of hydrogen can in theory be done at home or outside of government control and taxation. Electricity charging can also be considered as well but maybe the powers that be don't like the thought of people filling up their own cars with untaxed hydrogen?

How can hydrogen be produced at home in a manner that is positive in terms of EROEI? Never mind being positive in terms of cost versus profit.

northernmonkey wrote: ↑02 Jan 2024, 20:52

BritDownUnder wrote: ↑01 Jan 2024, 21:25 I can only see hydrogen being a suitable fuel source if batteries become less economic or the raw materials become unavailable, or if there is a requirement for propulsion in a remote inaccessible place where batteries are not available, or if 'refuelling' times of less than several minutes are required and long ranges are required. Otherwise the EROEI of hydrogen goes against it.

Just one other thought. Production of hydrogen can in theory be done at home or outside of government control and taxation. Electricity charging can also be considered as well but maybe the powers that be don't like the thought of people filling up their own cars with untaxed hydrogen?

How can hydrogen be produced at home in a manner that is positive in terms of EROEI? Never mind being positive in terms of cost versus profit.

It can't, but in some circumstances electricity supply from an isolated solar PV system might be stranded and not usable for anything else except for electrolysis of hydrogen at a EROEI<1.

Don't forget that most mechanised food production already has something like a 0.1 EROEI.

BritDownUnder wrote: ↑02 Jan 2024, 21:32

northernmonkey wrote: ↑02 Jan 2024, 20:52

BritDownUnder wrote: ↑01 Jan 2024, 21:25 I can only see hydrogen being a suitable fuel source if batteries become less economic or the raw materials become unavailable, or if there is a requirement for propulsion in a remote inaccessible place where batteries are not available, or if 'refuelling' times of less than several minutes are required and long ranges are required. Otherwise the EROEI of hydrogen goes against it.

Just one other thought. Production of hydrogen can in theory be done at home or outside of government control and taxation. Electricity charging can also be considered as well but maybe the powers that be don't like the thought of people filling up their own cars with untaxed hydrogen?

How can hydrogen be produced at home in a manner that is positive in terms of EROEI? Never mind being positive in terms of cost versus profit.

It can't, but in some circumstances electricity supply from an isolated solar PV system might be stranded and not usable for anything else except for electrolysis of hydrogen at a EROEI<1.

Don't forget that most mechanised food production already has something like a 0.1 EROEI.

Whist the terrible EROEI involved in industrial food production is a real issue, it is a secondary one. Food production is further downstream.

If the actual generation of usable energy costs more energy to generate than is contained in the generated usable energy itself, then its total a non starter except in very specific instances of one off usage where the benefits outweigh the costs.

As for your example of a domestic solar pv, it would logically make more energetic sense to convert that to electricity and consume the electricity directly as opposed to then converting the electricity to hydrogen prior to consumption with all of the energy losses incurred in the secondary conversion

northernmonkey wrote: ↑02 Jan 2024, 23:02

BritDownUnder wrote: ↑02 Jan 2024, 21:32

northernmonkey wrote: ↑02 Jan 2024, 20:52

How can hydrogen be produced at home in a manner that is positive in terms of EROEI? Never mind being positive in terms of cost versus profit.

It can't, but in some circumstances electricity supply from an isolated solar PV system might be stranded and not usable for anything else except for electrolysis of hydrogen at a EROEI<1.

Don't forget that most mechanised food production already has something like a 0.1 EROEI.

Whist the terrible EROEI involved in industrial food production is a real issue, it is a secondary one. Food production is further downstream.

If the actual generation of usable energy costs more energy to generate than is contained in the generated usable energy itself, then its total a non starter except in very specific instances of one off usage where the benefits outweigh the costs.

As for your example of a domestic solar pv, it would logically make more energetic sense to convert that to electricity and consume the electricity directly as opposed to then converting the electricity to hydrogen prior to consumption with all of the energy losses incurred in the secondary conversion

I think solar PV has a lifetime EROEI of more than 10 but on each charge or batch of hydrogen produced will have a EROEI < 1 due to the second law of thermodynamics. This doesn't matter because the energy input (the Sun) is free energy and infinite over a 100 million year timescale.

On the last point you made matching energy generated to energy required is one of the main issues of renewable electricity generation. Some see hydrogen as a useful store of electricity even if it has a lousy EROEI. In most cases a lithium ion batter beats hydrogen anytime but if the battery materials are not available or capital costs too expensive, or the refuelling time has to be very quick I can see hydrogen as a 'niche' storage/fuelling system. Hydrogen can also be used (very inefficiently in existing diesel engine systems so this might save on capital costs) We will see if this pans out. From what I can see hydrogen fuelling stations are not being built around the world like battery chargers are.

BritDownUnder wrote: ↑03 Jan 2024, 21:15 I think solar PV has a lifetime EROEI of more than 10 but on each charge or batch of hydrogen produced will have a EROEI < 1 due to the second law of thermodynamics. This doesn't matter because the energy input (the Sun) is free energy and infinite over a 100 million year timescale.

On the last point you made matching energy generated to energy required is one of the main issues of renewable electricity generation. Some see hydrogen as a useful store of electricity even if it has a lousy EROEI. In most cases a lithium ion batter beats hydrogen anytime but if the battery materials are not available or capital costs too expensive, or the refuelling time has to be very quick I can see hydrogen as a 'niche' storage/fuelling system. Hydrogen can also be used (very inefficiently in existing diesel engine systems so this might save on capital costs) We will see if this pans out. From what I can see hydrogen fuelling stations are not being built around the world like battery chargers are.

I didn't say the sun was not (effectively) infinite or that solar panels are not EROEI positive in terms of generating electricity (though that is debatable depending on the metric you use, but we'll leave that for now). I am saying, however, that, the negative EROEI of hydrogen production in terms of the energy in (electricity) to energy out (hydrogen) makes no sense given that you have used a form of energy to obtain it that was, in EROEI terms, a positive energy source (just). Thus, It matters little if the energy source you use to generate your final energy is infinite if the energy you get out the end is less than the energy you used to get it.

If the hydrogen is going to be used to power a home electrical generator, why not use the electricity generated by the PV instead and cut out the EROEI negative middle man?

If the hydrogen is going to be used to power an ICE vehicle/engine why not use the electricity to power an EV/electric motor and cut out the EROEI negative middle man?

There are an exceedingly small number of very specialist and particular instances where the negative EROEI of hydrogen makes any sense whatsoever.

On your point about the efficacy of hydrogen being seen as a useful energy store as opposed to an energy source, I can, perhaps, seen a limited merit in that. But, only limited. In terms of non-mobile storage, I'd wager deep cycle lead acid batteries will have a better EROEI than hydrogen

northernmonkey wrote: ↑31 Dec 2023, 16:04 The negative EROEI in hydrogen might also have something to do with it.

Energy Returned / Energy Invested.

In order for EROEI<0, then energy returned must be <0.

How does the process of creating hydrogen from say, water, with some small engine using energy Y to create the hydrogen which has energy X, which is LESS than Y maybe (EROEI>0 and EROEI<1), but how does this basic process not only NOT make any hydrogen, but actually makes energy......somewhere...somehow...disappear?

Does the water you are running electricity into get...colder? As oppsoed to just creating hydrogen and oxygen like it normally does?

johnny wrote: ↑04 Jan 2024, 01:16

northernmonkey wrote: ↑31 Dec 2023, 16:04 The negative EROEI in hydrogen might also have something to do with it.

Energy Returned / Energy Invested.

In order for EROEI<0, then energy returned must be <0.

How does the process of creating hydrogen from say, water, with some small engine using energy Y to create the hydrogen which has energy X, which is LESS than Y maybe (EROEI>0 and EROEI<1), but how does this basic process not only NOT make any hydrogen, but actually makes energy......somewhere...somehow...disappear?

Does the water you are running electricity into get...colder? As oppsoed to just creating hydrogen and oxygen like it normally does?

Nope.

In order for EROEI to not be <0, the energy out must equal or exceed the energy in. It doesn't matter what energy you get out. It must exceed the energy in.

I'll put in in financial terms as I suspect you might be better able to grasp this concept in such terms.

It doesn't matter if you make a million dollars on a deal if the deal costs you 1.5 million dollars.

Get it?

northernmonkey wrote: ↑04 Jan 2024, 01:27 In order for EROEI to not be <0, the energy out must equal or exceed the energy in.

Feel free to correct my equations up above? There are only two parts to this thing, we both know what the words are, and if energy out => the energy in, EROEI>=1

In order to be negative, one of the two terms must be negative. Putting energy in is defined as part of the process, to even calculate EROEI you have this idea of...I put energy IN. Therefore energy in by definition is >0. Otherwise there is no metric to discuss.

Therefore the only way you get a negative EROEI is if the top term, energy returned, is LESS than 0. So in my example, in trying to make hydrogen, you make energy...disappear...somehow. Hence the water getting colder crack.

northernonkey wrote: It doesn't matter what energy you get out. It must exceed the energy in.

Ignoring the 2nd Law of Thermodynamics hiccup in that statement, there are two parts to the equation. If energy out doesn't matter, then remove it from the equation and presto....you aren't talking about EROEI anymore but just....energy in.

northernmonkey wrote: I'll put in in financial term as I suspect you might be better able to grasp this concept.

You shouldn't. Energy isn't money, and I do physics, not money handling.

northernmonkey wrote: It doesn't matter if you make a million dollars on a deal if the deal costs you 1.5 million dollars.
Get it?

Yes. Money isn't energy. And you REALLY don't understand EROEI.

johnny wrote: ↑04 Jan 2024, 01:46

northernmonkey wrote: ↑04 Jan 2024, 01:27 In order for EROEI to not be <0, the energy out must equal or exceed the energy in.

Feel free to correct my equations up above? There are only two parts to this thing, we both know what the words are, and if energy out => the energy in, EROEI>=1

In order to be negative, one of the two terms must be negative. Putting energy in is defined as part of the process, to even calculate EROEI you have this idea of...I put energy IN. Therefore energy in by definition is >0. Otherwise there is no metric to discuss.

Therefore the only way you get a negative EROEI is if the top term, energy returned, is LESS than 0. So in my example, in trying to make hydrogen, you make energy...disappear...somehow. Hence the water getting colder crack.

northernonkey wrote: It doesn't matter what energy you get out. It must exceed the energy in.

Ignoring the 2nd Law of Thermodynamics hiccup in that statement, there are two parts to the equation. If energy out doesn't matter, then remove it from the equation and presto....you aren't talking about EROEI anymore but just....energy in.

northernmonkey wrote: I'll put in in financial term as I suspect you might be better able to grasp this concept.

You shouldn't. Energy isn't money, and I do physics, not money handling.

northernmonkey wrote: It doesn't matter if you make a million dollars on a deal if the deal costs you 1.5 million dollars.
Get it?

Yes. Money isn't energy. And you REALLY don't understand EROEI.

Okay, one more try:

https://en.wikipedia.org/wiki/Energy_re ... investment

EROEI = energy delivered/energy required to deliver that energy (hint: the first part of that equation needs to be bigger than the second part). Whilst the second law of thermodynamics requires that there is no such thing as a free lunch, that law is irrelevant to the above statement if the energetic cost of access to the energy required is less than the energetic profit of the energy delivered. Sure enough, the second law of dynamics must still apply at some point in the process. But, the cost is born by the sun (prior to the EROEI calculation described above) which, as we both know, can be regarded as a functionally infinite supply

To repeat, when the EROI of a source of energy is less than or equal to 1 (not 0), that energy source becomes a net "energy sink", and can no longer be used as a source of energy.

The EROEI of photovoltaics is above 1 (how much above 1 is a matter of debate). When the electricity produced in said manner is then employed to extract hydrogen from water, the EROEI is significantly below 1. Significantly enough, in fact, that the total, cumulative EROEI, from solar to hydrogen (due to the energy losses incurred in the two energy transfers) is below 1.

I don't think you can get a negative EROEI with the formula I am thinking of. I think in terms of EROEI > 1 is when you get more energy back than either the energy input to run your 'energy harvesting equipment' or the energy required to make your 'energy harvesting equipment'. There's a bit of difference between the two.
EROEI < 1 for the former is acceptable if you have an infinite energy source like the sun, or your energy produced is in a better form (i.e. more storable) than the energy input - think of making petrol from sunlight.
EROEI < 1 for the latter (energy harvesting equipment) makes no long term sense.

Hope you all get my line of thinking. There's at least two types of EROEI (and probably a few more like ESOEI for storage equipment like batteries or pump storage) and they will have different consequences for mankind.

You could also be a country like Australia that has little oil reserves of its own and spends a considerable proportion of its exports on importing petroleum (like 25%) but has a lot of solar energy and decides (based on both economic and national security reasons) to use EROEI < 1 energy conversion equipment to turn sunlight into petrol via water and CO2 from the air.

Hydrogen will be needed to produce ammonia for fertilisers and there's no real carbon neutral alternative to that.