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The sad fact is that with insatiable demand for lithium to power the electric revolution, every local environment where lithium is sourced is being destroyed.
https://www.wired.co.uk/article/lithium-batteries-environment-impact
The rich consumer countries as usual are paying no heed of the impact on poor and indigenously poplated environments.
The massive water consumption is the main issue.0 -
Things are getting real!
Seawalls to protect US against rising oceans could cost $416bn by 2040“You’re looking at close to half a trillion spent over the next 20 years and no one has thought about that. So the question is, who’s going to pay for that? Is it really going to be taxpayers? The current position of climate polluters is that they should pay nothing, and that’s just not tenable.”Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
The sad fact is that with insatiable demand for lithium to power the electric revolution, every local environment where lithium is sourced is being destroyed.
https://www.wired.co.uk/article/lithium-batteries-environment-impact
The rich consumer countries as usual are paying no heed of the impact on poor and indigenously poplated environments.
The massive water consumption is the main issue.
Keeping it positive (pun intended), for stationary storage, flow batts are looking good, and energy (not power) can be increased quite cheaply by simply increasing the storage capacity.Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
Hydrogen Fuel Cell technologies have had a lot of investment over the years. It always seems so tempting, but it never seems to make the grade.
The "right" way to produce the hydrogen would be via electrolysis from renewable electricity sources, however in the real world converting the electricity to hydrogen is only around 10% efficient, so is wasteful and uneconomic and hence why the hydrogen comes from fossil fuel processes. Kinda negating much of its reason for being. Plus it's only 30% efficient in converting stored energy into forward motion. Plus its made from precious metals making it horribly expensive, and it wears out and has to be replaced as part of a maintenance schedule.
With batteries the 10% goes to 100% (as there's no conversion), the 30% goes to 80%, but take off 7% for transmission losses = 25 times more efficient. We just need 3 or 4 years worth of energy density development of the batteries and ethically sourced lithium.
https://medium.com/predict/electric-or-hydrogen-the-future-of-personal-transportation-4e2a15fbe719 (as with too many "green" related links, beware of the vested interest)0 -
HiHydrogen Fuel Cell technologies have had a lot of investment over the years. It always seems so tempting, but it never seems to make the grade.
The "right" way to produce the hydrogen would be via electrolysis from renewable electricity sources, however in the real world converting the electricity to hydrogen is only around 10% efficient, so is wasteful and uneconomic and hence why the hydrogen comes from fossil fuel processes. Kinda negating much of its reason for being. Plus it's only 30% efficient in converting stored energy into forward motion. Plus its made from precious metals making it horribly expensive, and it wears out and has to be replaced as part of a maintenance schedule.
With batteries the 10% goes to 100% (as there's no conversion), the 30% goes to 80%, but take off 7% for transmission losses = 25 times more efficient. We just need 3 or 4 years worth of energy density development of the batteries and ethically sourced lithium.
https://medium.com/predict/electric-or-hydrogen-the-future-of-personal-transportation-4e2a15fbe719 (as with too many "green" related links, beware of the vested interest)
From previous research I thought that hydrogen electrolysis ranged up to around ~80% efficient (in terms of electricity used to create hydrogen embodied energy) and that there are now a number of fuel cells based on relatively inexpensive stainless steel plate stacks which have an electrical energy to heat production efficiency of around ~50%:~50% ...
The big problem with hydrogen is the application ... if it's to produce motive power you need to lug around plenty of mass, that's not the mass of the hydrogen itself, but the high pressure vessels that it's contained in because it's essentially boiled to become a gas at our atmospheric temperatures & pressures, which effectively reduces motive efficiency on the ground and really kills the economics for gas based propulsion in commercial heavier than air aircraft.
The case can be made for short cycle hydrocarbon fuels that are stable as a liquid at pressures & temperatures that they would be required to be stored & used at as this removes the requirement for cumbersome pressure or temperature managed storage, particularly so if they could be extracted & refined directly from the atmosphere at commercial costs & volumes ...
HTH
Z"We are what we repeatedly do, excellence then is not an act, but a habit. " ...... Aristotle
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Hi
From previous research I thought that hydrogen electrolysis ranged up to around ~80% efficient (in terms of electricity used to create hydrogen embodied energy) and that there are now a number of fuel cells based on relatively inexpensive stainless steel plate stacks which have an electrical energy to heat production efficiency of around ~50%:~50% ...
HTH
Z
Hiya. There's also the losses (energy consumption) from compression or liquefying, but as has been said (by you I think?) if the leccy input comes from low value marginal generation, then what the hell, let's full our boots.
Edit - sorry I misunderstood your final paragraph - so you are looking at low pressure use on site ...... cool, that helps, and I think there's an American guy who built such a system at his house, but he is ex-NASA or something like that.
I'm in a very positive mood lately, no idea why.Mart. Cardiff. 5.58 kWp PV systems (3.58 ESE & 2.0 WNW)
For general PV advice please see the PV FAQ thread on the Green & Ethical Board.0 -
HiMartyn1981 wrote: »Hiya. There's also the losses (energy consumption) from compression or liquefying, but as has been said (by you I think?) if the leccy input comes from low value marginal generation, then what the hell, let's full our boots.
Edit - sorry I misunderstood your final paragraph - so you are looking at low pressure use on site ...... cool, that helps, and I think there's an American guy who built such a system at his house, but he is ex-NASA or something like that.
I'm in a very positive mood lately, no idea why.
Accepted ... but 1kg of hydrogen contains ~33kWh of energy whereas compressing 1kg of hydrogen to 10kpsi consumes around 1.5kWh, so around 96% overall energy efficient as a process ... 96% of 'up to 80%' makes little more than a general rounding difference when comparing to the ~10% production efficiency being highlighted/questioned ....
HTH
Z"We are what we repeatedly do, excellence then is not an act, but a habit. " ...... Aristotle0 -
Martyn1981 wrote: »if the leccy input comes from low value marginal generation, then what the hell, let's full our boots.
I guess you're saying renewable electricity for which there is no demand at the time of production. One half of the renewable energy conundrum. Isn't the environmental need that this is addressed with storage solutions (batteries) to eliminate fossil fuels rather than be wasted in an unreliable supply (and having to be topped up with non marginal generation) supporting inefficient processes?0 -
From previous research I thought that hydrogen electrolysis ranged up to around ~80% efficient
From that Medium article:In reality that process would be too wasteful, as hydrolysis is rarely more than 10% efficient and at best under lab conditions 50% efficient.
:rotfl: Note my caveat about vested interests against that link! I'd love to see where he got that 10% from. It seems current technology is nearer 70% according to Wikipedia with an expectation of low eighties in ten years. It seems fossil fuel derived hydrogen is still generally cheaper though, so with the other factors (including the compression overhead, the lower energy density and thick heavy steel tanks...) it doesn't yet change the balance of the argument.0 -
HiI guess you're saying renewable electricity for which there is no demand at the time of production. One half of the renewable energy conundrum. Isn't the environmental need that this is addressed with storage solutions (batteries) to eliminate fossil fuels rather than be wasted in an unreliable supply (and having to be topped up with non marginal generation) supporting inefficient processes?
The issue is that at the moment a considerable amount of renewable energy generation curtailment happens because supply exceeds demand ... you can easily see this on both on-shore & off-shore sites where only a proportion of turbines are spinning, the rest having had the brakes applied or simply turned out of the air stream ...
Effectively, it's not the "electricity for which there is no demand at the time of production" that becomes the issue, it's the control rooms that call for generation to be scaled back or stopped (curtailment) because there is no demand to satisfy, although there may be a requirement for compensation to be paid for not generating, so storage becomes an ideal short & medium term storage solution ...
Short term energy storage using hydrogen could be highly distributed and possibly linked to modular high pressure storage (5000-10000psi) supplying local PEM stacks when required, or more strategic storage in low pressure mass storage in the likes of underground caverns (salt etc) or fairly cheap overground storage based on old technology gasometers to feed either large scale fuel cells, or more likely comparatively cheap hydrogen ICE generators as the total fuel efficiency & cycle cost can only realistically be measured against lost opportunity, therefore marginal ...
This is really what's behind the arguments that those opposed to renewable energy employ when concentrating on relative efficiencies and capacity loading factors as opposed to the real issues of energy unit cost & associated impact, whether sustainable, environmental or health related ...
HTH
Z"We are what we repeatedly do, excellence then is not an act, but a habit. " ...... Aristotle0
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