Thomas Koenig <tkoenig@netcologne.de> writes:
>That something has been done is no guarantee that it made sense.

In the present case, given that the power companies still offer lower
rates for Nachtstrom after many decades, it obviously still makes
sense for them (and despite claims of daytime surplus power from
renewable energy, they usually still turn on Nachtstrom at night).

And it certainly satisfies the original problem description: "control
a million warm water heaters".

>You have to look at all the aspects, also the negative ones,
>which is hard work and all to often overlooked.

You may want to move the goalposts, but here just present a generality.

- anton
--
'Anyone trying for "industrial quality" ISA should avoid undefined behavior.'
Mitch Alsup, <c17fcd89-f024-40e7-a594-88a85ac10d20o@googlegroups.com>

Brett wrote:
> MitchAlsup <MitchAlsup@aol.com> wrote:
>> The cost to require the place and bring the building up to code was more than
>> the cost of all the machines put together (more than $15,000) !!!
>
> Wiring a room is something I did as a child to help my family, remove a
> zero if you do the job yourself. And the government does not need to know
> unless you upgrade the main breaker box, which you won’t. Put a small
> breaker box in the room and run surface tube to all the new outlet boxes.
> When done run the big expensive wire(s) to your main box, flip the main
> breaker off and wire it up to big breakers. Or pay a Mexican $100 to do the
> last step, just pick up a Mexican day laborer waiting at your local
> building supply store, and ask “electrical work”.
>
> If the government does find out all they can do is inspect it and ask that
> you fix any mistakes. Electricition’s always make some mistakes, not a big
> deal.
>
> Almost all electrical work today is done by unlicensed unskilled untrained
> illegal Mexican labor. The only guy who can speak English is the Forman you
> got the quote from, who you will never see on the job site.
>
> You will feel SO good when the job is done dropping a zero off the quote
> doing it yourself. Or even just paying the Mexican labor yourself and
> saving 3/4ths the cost.

Here in Norway you will feel really bad when your house burns down and
the insurance company inspectors determine that at least part of the
electrical work must have been done by non-certified workers:

This is gross negligence and invalidates the fire insurance, even if
they cannot point to the electrical system as the source of the fire.

Terje

--
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

Terje Mathisen <terje.mathisen@tmsw.no> wrote:
> Brett wrote:
>> MitchAlsup <MitchAlsup@aol.com> wrote:
>>> The cost to require the place and bring the building up to code was more than
>>> the cost of all the machines put together (more than $15,000) !!!
>>
>> Wiring a room is something I did as a child to help my family, remove a
>> zero if you do the job yourself. And the government does not need to know
>> unless you upgrade the main breaker box, which you won’t. Put a small
>> breaker box in the room and run surface tube to all the new outlet boxes.
>> When done run the big expensive wire(s) to your main box, flip the main
>> breaker off and wire it up to big breakers. Or pay a Mexican $100 to do the
>> last step, just pick up a Mexican day laborer waiting at your local
>> building supply store, and ask “electrical work”.
>>
>> If the government does find out all they can do is inspect it and ask that
>> you fix any mistakes. Electricition’s always make some mistakes, not a big
>> deal.
>>
>> Almost all electrical work today is done by unlicensed unskilled untrained
>> illegal Mexican labor. The only guy who can speak English is the Forman you
>> got the quote from, who you will never see on the job site.
>>
>> You will feel SO good when the job is done dropping a zero off the quote
>> doing it yourself. Or even just paying the Mexican labor yourself and
>> saving 3/4ths the cost.
>
> Here in Norway you will feel really bad when your house burns down and
> the insurance company inspectors determine that at least part of the
> electrical work must have been done by non-certified workers:
>
> This is gross negligence and invalidates the fire insurance, even if

Then spend the $50 for an inspection.

Household wiring is idiot proof, especially when you run the wires in
surface tubes.
The only source of failure is cheeping out on the big expensive wire
between boxes and putting in a wire underrated for the breaker. Don’t
overstuff your electrical boxes, look up the max wires per box size. Four
holes does not mean four wires.

Heard a story of a fool who wired his 50 amp electric stove with a 20 amp
wire to save $300, moron. 50 amp wire is expensive, put the breaker box in
the closest corner.

Your electrical work is done today in the US by unlicensed unskilled
untrained illegal Mexican labor. That is why inspections are important.

It is entertaining to watch the illegals work and and test the circuits by
plugging in a tool and watching the circuit breaker blow because they
botched the job. Five minutes later the three way light switch is rewired
correctly and working.

You will find the Mexican laborers early in the morning crowded on the
sidewalk at the least visible entrance to the hardware store parking lot.
Just ask “electrical work”, they have very limited English skills. Goggle
audio translate on your phone is helpful.

On Mon, 2 Aug 2021 21:17:08 -0700, "Chris M. Thomasson"
<chris.m.thomasson.1@gmail.com> wrote:

>I am wondering what you think about using a metal hydride to store hydrogen?
>
>https://youtu.be/Ytg23mDd1a4

I generally am in favor of much greater use of hydrogen - provided
that it is cleanly produced using water and electricity.

Unfortunately most hydrogen currently is extracted from natural gas.
Extracting the hydrogen results in nitrogen for fertilizer, so it's
not wasted in that use, but natural gas supplies are limited and far
too much of it is just being burned to generate electricity.

Storing hydrogen in solid hydrides is an interesting idea - one I
learned about years ago in a documentary about Stanford Ovshinsky and
his NiMH based solutions. [Sorry don't have a link]

What wasn't explained then was how the hydrogen gas could be gotten
/out/ of solid form fast enough to supply it in bulk to an engine.
This video about Bob Lazar answers that question at least with respect
to his LiMH solution.

But the problem that remains is that metals that easily form hydrides
for the most part are toxic ... some of them /highly/ toxic. Which
takes us back to "batteries are dirty".

A hydrogen vehicle using solid hydride storage won't explode if it's
in an accident, but it still may result in a toxic mess - one that is
a lot harder to clean up than a simple gasoline/diesel spill.

YMMV.

On 31/07/2021 20:10, Thomas Koenig wrote:
> Branimir Maksimovic <branimir.maksimovic@gmail.com> schrieb:
>> On 2021-07-31, Thomas Koenig <tkoenig@netcologne.de> wrote:
>>> Branimir Maksimovic <branimir.maksimovic@gmail.com> schrieb:
>>>
>>>> Well probably you are right, but these are big numbers :P
>>>> Mining of bitcoins nowadays is only done on ASiC (GPU is pointless),
>>>
>>> There are enough people doing so to make GPUs rather scarce
>>> and expensive, unfortunately.
>> I think that GPU mining is done for newer cryptocurrencies.
>> Or if they just want to pay electricity bills without profit :P
>
> Or not pay their electricity bills, which of course increases
> the profit margin by quite a bit, unless they get caught:
> https://www.bbc.com/news/uk-england-birmingham-57280115
>

For many cryptominers, they don't pay the electricity bill because mummy
and daddy pay it. Others avoid paying for it by tricking malware
victims into running the software for them.

There are also more professional setups that abuse tax breaks and cheap
commercial electricity by claiming to be "data centres" and promising
new local jobs in modern industry. They can claim to be "green" by
using, say, hydroelectric power in Norway or geothermal power in
Iceland, but in reality they are far from "green" as they waste
electricity that could be doing something useful.

On 01/08/2021 21:35, Terje Mathisen wrote:
> John Dallman wrote:
>> In article <03a02706-ce03-4604-bd58-66cbb89a7d7cn@googlegroups.com>,
>> already5chosen@yahoo.com (Michael S) wrote:
>>
>>> Norway currently (actually, 2014, I found no up to date data) is
>>> World #2 (after Iceland and ahead of Bahrain) in electric power
>>> consumption per capita.
>>
>> All three countries have large aluminium refining industries. This uses
>> vast quantities of electricity, and hence is done where electricity is
>> cheapest.
>
> Also very relevant: An aluminium smelter can afford to delay the process
> for some minutes or even hours when available power is sparse/expensive.
>
> This is far easier than trying to control a million warm water heaters,
> but we will end up doing that as well, along with intelligent home car
> charge points.
>

The most important aspect of controlling high-power appliances at home
(of which electric car chargers are the biggest) is reducing the peak
loads on the networks, rather than at the power generation end. The
power grid wires, transformers, distribution points, etc., all need to
be dimensioned to handle the peak loads - so reducing those peaks is a
big win.

(Ideally we should switch to high voltage DC networks, which are much
more efficient for transmission. And we should also have local energy
storage in flow batteries, iron-air batteries, or the like.)

George Neuner <gneuner2@comcast.net> schrieb:
> On Mon, 2 Aug 2021 21:17:08 -0700, "Chris M. Thomasson"
><chris.m.thomasson.1@gmail.com> wrote:
>
>>I am wondering what you think about using a metal hydride to store hydrogen?
>>
>>https://youtu.be/Ytg23mDd1a4
>
> I generally am in favor of much greater use of hydrogen - provided
> that it is cleanly produced using water and electricity.

It also has some very unpleasant properties regarding explosion
safety.

If you look at https://gestis.dguv.de/data?name=007010&lang=en
you will notice

- its exremely high range of explosion limits (from 4.0% to 77%)
- Its explosion group: IIC

The latter means that the energy to ignite a hydrogen/air mixture
is extremely low; it shares that class with only two other common
substances, acetylene and carbon disulfide. IIC is _bad_, most
explosion-proff electrical equipment is only rated IIB because IIC
drives up the cost like crazy.

The minimum ignition enery of hydrogen is 0.016 Millijoule (listed
in TRGS 727, appedix G, if you're interested in a source - TRGS is
"Technische Regeln Gefahrstoffe", the German technical guidelines
for hazardous substances).

This means that almost any electrostatic discharge can ignite
hydrogen.

Being a very small molecule, it also has a very high diffusion
coefficient and a high speed of sound, which means that it leaks
out of gasked or leaks faster than anything else.

Because hydrogen burns without a visible flame, it can burn
undetected for a long time, and a small flame can serve as an
ignition source for something else. You an only see it with an
IR detector, especially if it burns below insulation.

In an industrial context, this can be managed - by long and ardous
safety discussions, expensive measures and regular inspections.
But then again, the chemical industry is safety-crazy and is willing
to spend large amounts of money and effort on avoiding explosions.
And even so, they do not always succeed (see the recent tragic
accident not far from where I live).

Putting hydrogen into private customer's hands, where the balance
between safety and cost is much more on the cost side, and safety
standards are _far_ lower...

In article <seag04$cjj$1@gioia.aioe.org>, chris.m.thomasson.1@gmail.com
(Chris M. Thomasson) wrote:

> I am wondering what you think about using a metal hydride to store
> hydrogen? https://youtu.be/Ytg23mDd1a4

That seems to be the same Bob Lazar as the Area 51 conspiracy theorist. I
would not trust /anything/ he said that was science-related.

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

John

On Wednesday, August 4, 2021 at 5:37:01 AM UTC-5, Thomas Koenig wrote:
> George Neuner <gneu...@comcast.net> schrieb:
> > On Mon, 2 Aug 2021 21:17:08 -0700, "Chris M. Thomasson"
> ><chris.m.t...@gmail.com> wrote:
> >
> >>I am wondering what you think about using a metal hydride to store hydrogen?
> >>
> >>https://youtu.be/Ytg23mDd1a4
> >
> > I generally am in favor of much greater use of hydrogen - provided
> > that it is cleanly produced using water and electricity.
> It also has some very unpleasant properties regarding explosion
> safety.
>
> If you look at https://gestis.dguv.de/data?name=007010&lang=en
> you will notice
>
> - its exremely high range of explosion limits (from 4.0% to 77%)
> - Its explosion group: IIC
>
> The latter means that the energy to ignite a hydrogen/air mixture
> is extremely low; it shares that class with only two other common
> substances, acetylene and carbon disulfide. IIC is _bad_, most
> explosion-proff electrical equipment is only rated IIB because IIC
> drives up the cost like crazy.
>
> The minimum ignition enery of hydrogen is 0.016 Millijoule (listed
> in TRGS 727, appedix G, if you're interested in a source - TRGS is
> "Technische Regeln Gefahrstoffe", the German technical guidelines
> for hazardous substances).
>
> This means that almost any electrostatic discharge can ignite
> hydrogen.
>
> Being a very small molecule, it also has a very high diffusion
> coefficient and a high speed of sound, which means that it leaks
> out of gasked or leaks faster than anything else.
<
I was lead to believe that Helium leaks faster due to its smaller molecular
size. Buy Hydrogen does diffuse faster due to its low molecular weight.
>
> Because hydrogen burns without a visible flame, it can burn
> undetected for a long time, and a small flame can serve as an
> ignition source for something else. You an only see it with an
> IR detector, especially if it burns below insulation.
>
> In an industrial context, this can be managed - by long and ardous
> safety discussions, expensive measures and regular inspections.
> But then again, the chemical industry is safety-crazy and is willing
> to spend large amounts of money and effort on avoiding explosions.
> And even so, they do not always succeed (see the recent tragic
> accident not far from where I live).
>
> Putting hydrogen into private customer's hands, where the balance
> between safety and cost is much more on the cost side, and safety
> standards are _far_ lower...
<
And then there is that problem of efficiency--trying to get back that
14.7 KJ/mole--all in all batteries are easier to get efficient.

A big issue with using H2 as a battery/storage medium is the cost of
compressing it sufficiently to make it transportable, while keeping it
contained in vessels that are strong enough to make it safe.

Unless you want to also run a small turbine with the expanding gas, then
the compression energy is a pure loss.

If/when the round trip energy efficiency from electricity via
electrolysis to H2 and back to electricity is 30+ percent then it is
very hard to compete with the 80-95% available to regular batteries.

Terje

MitchAlsup wrote:
> On Wednesday, August 4, 2021 at 5:37:01 AM UTC-5, Thomas Koenig wrote:
>> George Neuner <gneu...@comcast.net> schrieb:
>>> On Mon, 2 Aug 2021 21:17:08 -0700, "Chris M. Thomasson"
>>> <chris.m.t...@gmail.com> wrote:
>>>
>>>> I am wondering what you think about using a metal hydride to store hydrogen?
>>>>
>>>> https://youtu.be/Ytg23mDd1a4
>>>
>>> I generally am in favor of much greater use of hydrogen - provided
>>> that it is cleanly produced using water and electricity.
>> It also has some very unpleasant properties regarding explosion
>> safety.
>>
>> If you look at https://gestis.dguv.de/data?name=007010&lang=en
>> you will notice
>>
>> - its exremely high range of explosion limits (from 4.0% to 77%)
>> - Its explosion group: IIC
>>
>> The latter means that the energy to ignite a hydrogen/air mixture
>> is extremely low; it shares that class with only two other common
>> substances, acetylene and carbon disulfide. IIC is _bad_, most
>> explosion-proff electrical equipment is only rated IIB because IIC
>> drives up the cost like crazy.
>>
>> The minimum ignition enery of hydrogen is 0.016 Millijoule (listed
>> in TRGS 727, appedix G, if you're interested in a source - TRGS is
>> "Technische Regeln Gefahrstoffe", the German technical guidelines
>> for hazardous substances).
>>
>> This means that almost any electrostatic discharge can ignite
>> hydrogen.
>>
>> Being a very small molecule, it also has a very high diffusion
>> coefficient and a high speed of sound, which means that it leaks
>> out of gasked or leaks faster than anything else.
> <
> I was lead to believe that Helium leaks faster due to its smaller molecular
> size. Buy Hydrogen does diffuse faster due to its low molecular weight.
>>
>> Because hydrogen burns without a visible flame, it can burn
>> undetected for a long time, and a small flame can serve as an
>> ignition source for something else. You an only see it with an
>> IR detector, especially if it burns below insulation.
>>
>> In an industrial context, this can be managed - by long and ardous
>> safety discussions, expensive measures and regular inspections.
>> But then again, the chemical industry is safety-crazy and is willing
>> to spend large amounts of money and effort on avoiding explosions.
>> And even so, they do not always succeed (see the recent tragic
>> accident not far from where I live).
>>
>> Putting hydrogen into private customer's hands, where the balance
>> between safety and cost is much more on the cost side, and safety
>> standards are _far_ lower...
> <
> And then there is that problem of efficiency--trying to get back that
> 14.7 KJ/mole--all in all batteries are easier to get efficient.
>

--
- <Terje.Mathisen at tmsw.no>
"almost all programming can be viewed as an exercise in caching"

On 8/2/2021 9:17 PM, Chris M. Thomasson wrote:
> On 8/2/2021 6:56 PM, George Neuner wrote:
>> On Mon, 2 Aug 2021 11:34:11 -0700, Ivan Godard
>> <ivan@millcomputing.com> wrote:
>>
>>> On 8/2/2021 10:58 AM, Anton Ertl wrote:
>>>> Thomas Koenig <tkoenig@netcologne.de> writes:
>>>>> Terje Mathisen <terje.mathisen@tmsw.no> schrieb:
>>>>>
>>>>>> If/when you first have to persuade one million home owners to replace
>>>>>> their currently working water heater with one that has remote control
>>>>>> capability, you are facing a very uphill struggle.
>>>>>
>>>>> It is also a waste, or should I say, use of resources - those new
>>>>> heaters have to be manufactured.
>>>>
>>>> Reading you two, one might think that it's impossible.  Reality check:
>>>> It has been done.  In the usual case not by replacing existing and
>>>> working heaters, but by getting into new buildings.  I guess there are
>>>> also some cases where the new heater replaced a failed or
>>>> psychologically obsolete one, but the infrastructure would have needed
>>>> to be already set up.
>>>>
>>>> As for resource usage, an alternative is to store the electricity
>>>> generated during low-demand times in pumped-storage hydroelectric
>>>> facilities.  Some years ago they spent EUR 400M on the Reisseck II
>>>> facility (which mainly connects two older systems to increase the
>>>> pumped-storage capacity)
>>>> <https://www.verbund.com/de-at/ueber-verbund/news-presse/presse/2016/10/07/reisseck2>.
>>>>
>>>> Spending some money on meters and to convince builders to put in extra
>>>> wiring and heaters with an isolated tank was probably not that
>>>> expensive in comparison, and the raw material usage probably not that
>>>> expensive, either.
>>>>
>>>> - anton
>>>>
>>>
>>> Would rewiring the house be more or less expensive than installing a
>>> battery that you charge at night rates?
>>
>> An interesting question if you consider the environmental costs of
>>   - constructing the battery,
>>   - generating the energy to repeatedly charge it, and
>>   - recycling the battery when it no longer works
>>
>> Batteries are among the environmentally dirtiest of technologies ...
>> right up there with semiconductors and solar cells.
>>
>> Then to charge a battery requires generating more energy than the
>> battery will hold. Depending on the chemistry, it may take a lot more
>> energy.
>>
>> YMMV.
>>
>
> I am wondering what you think about using a metal hydride to store
> hydrogen?
>
> https://youtu.be/Ytg23mDd1a4

As others have pointed out, there are a lot of problems with this.

But, for obvious reasons, batteries are a major subject of research and
development. There are lots of possibilities. One that is intriguing
to me is Iron.

https://www.sciencedirect.com/science/article/pii/S2468067219300318

Also note that there is a big difference between "user side" batteries
and "utility scale" batteries. Specifically some technologies, such as
flow batteries, are only useful for utility scale.

I don't know how it will work out, but in general we are making slow but
steady progress.

--
- Stephen Fuld
(e-mail address disguised to prevent spam)

Stephen Fuld <sfuld@alumni.cmu.edu.invalid> schrieb:

> As others have pointed out, there are a lot of problems with this.
>
> But, for obvious reasons, batteries are a major subject of research and
> development. There are lots of possibilities. One that is intriguing
> to me is Iron.
>
> https://www.sciencedirect.com/science/article/pii/S2468067219300318

This DIY approach that they recommend sounds highly dangerous,
especially since they casually mention generation of hydrogen:

"At higher voltages, hydrogen and oxygen production by the
electrolysis of water may be significant and can present an
explosion hazard."

Yep, very much so.

Another thing they casually mention is, as a criterion,

"Stability and repeatability in 12 cycles of charging and
discharging."

C'mon. 12 cycles of charging and discharging?

There may be progress along these lines, but this is not it.

On Wednesday, August 4, 2021 at 10:33:10 AM UTC-5, Stephen Fuld wrote:
> On 8/2/2021 9:17 PM, Chris M. Thomasson wrote:
> > On 8/2/2021 6:56 PM, George Neuner wrote:
> >> On Mon, 2 Aug 2021 11:34:11 -0700, Ivan Godard
> >> <iv...@millcomputing.com> wrote:
> >>
> >>> On 8/2/2021 10:58 AM, Anton Ertl wrote:
> >>>> Thomas Koenig <tko...@netcologne.de> writes:
> >>>>> Terje Mathisen <terje.m...@tmsw.no> schrieb:
> >>>>>
> >>>>>> If/when you first have to persuade one million home owners to replace
> >>>>>> their currently working water heater with one that has remote control
> >>>>>> capability, you are facing a very uphill struggle.
> >>>>>
> >>>>> It is also a waste, or should I say, use of resources - those new
> >>>>> heaters have to be manufactured.
> >>>>
> >>>> Reading you two, one might think that it's impossible. Reality check:
> >>>> It has been done. In the usual case not by replacing existing and
> >>>> working heaters, but by getting into new buildings. I guess there are
> >>>> also some cases where the new heater replaced a failed or
> >>>> psychologically obsolete one, but the infrastructure would have needed
> >>>> to be already set up.
> >>>>
> >>>> As for resource usage, an alternative is to store the electricity
> >>>> generated during low-demand times in pumped-storage hydroelectric
> >>>> facilities. Some years ago they spent EUR 400M on the Reisseck II
> >>>> facility (which mainly connects two older systems to increase the
> >>>> pumped-storage capacity)
> >>>> <https://www.verbund.com/de-at/ueber-verbund/news-presse/presse/2016/10/07/reisseck2>.
> >>>>
> >>>> Spending some money on meters and to convince builders to put in extra
> >>>> wiring and heaters with an isolated tank was probably not that
> >>>> expensive in comparison, and the raw material usage probably not that
> >>>> expensive, either.
> >>>>
> >>>> - anton
> >>>>
> >>>
> >>> Would rewiring the house be more or less expensive than installing a
> >>> battery that you charge at night rates?
> >>
> >> An interesting question if you consider the environmental costs of
> >> - constructing the battery,
> >> - generating the energy to repeatedly charge it, and
> >> - recycling the battery when it no longer works
> >>
> >> Batteries are among the environmentally dirtiest of technologies ...
> >> right up there with semiconductors and solar cells.
> >>
> >> Then to charge a battery requires generating more energy than the
> >> battery will hold. Depending on the chemistry, it may take a lot more
> >> energy.
> >>
> >> YMMV.
> >>
> >
> > I am wondering what you think about using a metal hydride to store
> > hydrogen?
> >
> > https://youtu.be/Ytg23mDd1a4
> As others have pointed out, there are a lot of problems with this.
>
> But, for obvious reasons, batteries are a major subject of research and
> development. There are lots of possibilities. One that is intriguing
> to me is Iron.
>
> https://www.sciencedirect.com/science/article/pii/S2468067219300318
<
The energy storage profile looks a lot more like a super capacitor than a battery.
>
> Also note that there is a big difference between "user side" batteries
> and "utility scale" batteries. Specifically some technologies, such as
> flow batteries, are only useful for utility scale.
>
> I don't know how it will work out, but in general we are making slow but
> steady progress.
> --
> - Stephen Fuld
> (e-mail address disguised to prevent spam)

On 8/4/2021 9:58 AM, Thomas Koenig wrote:
> Stephen Fuld <sfuld@alumni.cmu.edu.invalid> schrieb:
>
>> As others have pointed out, there are a lot of problems with this.
>>
>> But, for obvious reasons, batteries are a major subject of research and
>> development. There are lots of possibilities. One that is intriguing
>> to me is Iron.
>>
>> https://www.sciencedirect.com/science/article/pii/S2468067219300318
>
> This DIY approach that they recommend sounds highly dangerous,
> especially since they casually mention generation of hydrogen:

I apologize to all. I pasted the wrong link. :-(

https://www.dailymail.co.uk/sciencetech/article-9814873/Scientists-develop-iron-air-battery-stores-electricity-days.html

--
- Stephen Fuld
(e-mail address disguised to prevent spam)

On Wed, 4 Aug 2021 15:44:23 +0200, Terje Mathisen
<terje.mathisen@tmsw.no> wrote:

>A big issue with using H2 as a battery/storage medium is the cost of
>compressing it sufficiently to make it transportable, while keeping it
>contained in vessels that are strong enough to make it safe.
>
>Unless you want to also run a small turbine with the expanding gas, then
>the compression energy is a pure loss.

Right. Which is why the idea is to store it chemically in solid form.

There still are dangers - primarily heat. Hydrides are created
chemically when hydrogen is introduced to the bonding material, and
that process is exothermic. Storage tanks may have to be cooled while
being charged. Then you have to heat the hydride to release the
hydrogen again. Since it is a solid, it has to be heated in place in
the storage tank. So you have heaters, thermocouples, wiring, etc.
all in close proximity to (small amounts of) gaseous hydrogen.

Then you need to worry about leaks in the gas phase side of the system
where the hydrogen may mix with oxygen.

And - as I said in another post - the bonding materials typically are
toxic alkali or trans metals. The bonded hydrides won't explode, but
they will burn if ignited, and will cause chemical injuries if handled
improperly.

>If/when the round trip energy efficiency from electricity via
>electrolysis to H2 and back to electricity is 30+ percent then it is
>very hard to compete with the 80-95% available to regular batteries.
>
>Terje

Stephen Fuld <sfuld@alumni.cmu.edu.invalid> schrieb:
> On 8/4/2021 9:58 AM, Thomas Koenig wrote:
>> Stephen Fuld <sfuld@alumni.cmu.edu.invalid> schrieb:
>>
>>> As others have pointed out, there are a lot of problems with this.
>>>
>>> But, for obvious reasons, batteries are a major subject of research and
>>> development. There are lots of possibilities. One that is intriguing
>>> to me is Iron.
>>>
>>> https://www.sciencedirect.com/science/article/pii/S2468067219300318
>>
>> This DIY approach that they recommend sounds highly dangerous,
>> especially since they casually mention generation of hydrogen:
>
> I apologize to all. I pasted the wrong link. :-(
>
> https://www.dailymail.co.uk/sciencetech/article-9814873/Scientists-develop-iron-air-battery-stores-electricity-days.html

Let's look at the size of that thing... Assume we want to power
Germany (~ 80 GW = 8e10 W electrical power requirement) during
three weeks (1.8e6 seconds). This gives us 1.45e17 Joule we need
to store, or 4e13 W h. German Wikipedia gives 150 Wh/kg as an
upper limit of what can be realized in practice, so we need around
2.7e 11 kg for this, or 270 million tons of iron, or about twice
of what the EU produces as steel in a year. Doable, but HUGE.

CO2 emissions will not be low.

Now, the interesting thing is how many loading cycles this type
of battery supports and if we have to replace 270 million tons of
iron every one, two, five, ten, twenty, fifty or a hundred years...

Chris M. Thomasson wrote:
> I am wondering what you think about using a metal hydride to store hydrogen?
> https://youtu.be/Ytg23mDd1a4
Hydrogen has extremely poor energy cycle efficiency and is one of the most inconvenient substances to store.
It looks very advanced as it serves as rocket fuel and only produces water when burned. But the reality is that hydrogen is a dead end. For every practical purpose li-ion batteries are better. In the space industry it is losing to the methane. In aviation, synthetic fuels are the best solution, unless it is necessary to pre-cool the air in the engine (Skylon).
There is only one application where hydrogen should be used - modern airships. Unfortunately, people prefer to waste helium.

Tim Rentsch wrote:
> Dell is no longer shipping energy-hungry gaming PCs to
> certain states in America because they demand more energy
> than local standards allow.
>
> Customers seeking to purchase, for example, an Alienware
> Aurora Ryzen Edition R10 Gaming Desktop from Dell's website
> and have it shipped to California are now presented with a
> message that tells buyers they're out of luck.
>
> "This product cannot be shipped to the states of California,
> Colorado, Hawaii, Oregon, Vermont or Washington due to power
> consumption regulations adopted by those states," the
> website says. "Any orders placed that are bound for those
> states will be canceled."

It makes no sense to heat the water without making any useful computations.
We need water heaters that can act as water cooling for the hosted electronics.
Any high-performance computer / console system should be installed there in the racks and use the fiber optic connection to the living room. This way the law can be circumvented without braking its spirit.
The ideal system should be a hybrid with molten metal battery.

> ...
>
> Such concern about energy efficiency appears to be
> appropriate given the findings of a 2015 Semiconductor
> Industry Association report that, given a benchmark system
> of 10**-14 Joules/per bit transition, "computing will
> not be sustainable by 2040, when the energy required for
> computing will exceed the estimated world's energy
> production."
Not really, there is a free market that is the best distributed optimization algorithm possible.
Every artificial limitation is a misallocation of resources, a lesson the neo-Marxists have not learned.

> Not really, there is a free market that is the best distributed
> optimization algorithm possible.

While some theoretical model like the Turing machine degrades quite
gracefully when implemented in real life (most of the theory largely
still holds for real computers despite their lack of an infinite tape,
for example), that is far from the case for the free market
theoretical model.

> Every artificial limitation is a misallocation of resources, a lesson
> the neo-Marxists have not learned.

You seem quite happy to ignore the enormous amount of artificial
limitations that need to be implemented to get even a very crude
approximation of the free market model in the real world.

Stefan

piątek, 6 sierpnia 2021 o 17:15:34 UTC+2 Stefan Monnier napisał(a):
> > Not really, there is a free market that is the best distributed
> > optimization algorithm possible.
> While some theoretical model like the Turing machine degrades quite
> gracefully when implemented in real life (most of the theory largely
> still holds for real computers despite their lack of an infinite tape,
> for example), that is far from the case for the free market
> theoretical model.
Would you prefer instead an imperfect real implementation of ideal bureaucratic delusions?
> > Every artificial limitation is a misallocation of resources, a lesson
> > the neo-Marxists have not learned.
> You seem quite happy to ignore the enormous amount of artificial
> limitations that need to be implemented to get even a very crude
> approximation of the free market model in the real world.
It is not a reason to weaken market forces even more.
Free market happens. The size of the fruit and the amount of nectar are determined by the biological free market, where different species collaborate spontaneously. Eating fruit and drinking nectar is a business transaction.

> It is not a reason to weaken market forces even more.
> Free market happens. The size of the fruit and the amount of nectar are
> determined by the biological free market, where different species
> collaborate spontaneously. Eating fruit and drinking nectar is
> a business transaction.

That is an illusion.

The free market is based on the notion of "cost". The cost of lives,
the cost of ecological impact, the cost of trauma, etc... these aren't
inherently quantified, so your "free market" necessarily needs to be
built on top of very subjective and politically motivated choices (and
often enforced by the threat of retaliation).
It doesn't "just happen" any more than war "just happens".

Stefan

On Friday, August 6, 2021 at 5:06:09 AM UTC-5, pec...@gmail.com wrote:
> Chris M. Thomasson wrote:
> > I am wondering what you think about using a metal hydride to store hydrogen?
> > https://youtu.be/Ytg23mDd1a4
> Hydrogen has extremely poor energy cycle efficiency and is one of the most inconvenient substances to store.
> It looks very advanced as it serves as rocket fuel and only produces water when burned. But the reality is that hydrogen is a dead end. For every practical purpose li-ion batteries are better. In the space industry it is losing to the methane.
<
Space X is using Kerosene
I think Blue Origins is too.
A few percent down on thrust/Kg but the rocket does not have to have insulation so it breaks even.
<
> In aviation, synthetic fuels are the best solution, unless it is necessary to pre-cool the air in the engine (Skylon).
> There is only one application where hydrogen should be used - modern airships. Unfortunately, people prefer to waste helium.

MitchAlsup <MitchAlsup@aol.com> schrieb:
> On Friday, August 6, 2021 at 5:06:09 AM UTC-5, pec...@gmail.com wrote:
>> Chris M. Thomasson wrote:
>> > I am wondering what you think about using a metal hydride to store hydrogen?
>> > https://youtu.be/Ytg23mDd1a4
>> Hydrogen has extremely poor energy cycle efficiency and is one of the most inconvenient substances to store.
>> It looks very advanced as it serves as rocket fuel and only produces water when burned. But the reality is that hydrogen is a dead end. For every practical purpose li-ion batteries are better. In the space industry it is losing to the methane.
><
> Space X is using Kerosene

The Raptor Engine (the one that is driving the Starship)
uses Methane/LoX. Merlin, which drives the Falcon 9 and the
not-very-much used Falcon Heavy, uses rocket-grade Kerosene
(RP-1).

piątek, 6 sierpnia 2021 o 18:50:58 UTC+2 MitchAlsup napisał(a):
> On Friday, August 6, 2021 at 5:06:09 AM UTC-5, pec...@gmail.com wrote:
> > Chris M. Thomasson wrote:
> > > I am wondering what you think about using a metal hydride to store hydrogen?
> > > https://youtu.be/Ytg23mDd1a4
> > Hydrogen has extremely poor energy cycle efficiency and is one of the most inconvenient substances to store.
> > It looks very advanced as it serves as rocket fuel and only produces water when burned. But the reality is that hydrogen is a dead end. For every practical purpose li-ion batteries are better. In the space industry it is losing to the methane.
> <
> Space X is using Kerosene
> I think Blue Origins is too.
> A few percent down on thrust/Kg but the rocket does not have to have insulation so it breaks even.
Not really. Liquid methane Raptor - 382s ISP, kerosene RD-180 - 338s ISP. 13% better, but the benefits are exponential. Methane requires the same isolation as LOX. When you compare SSTO with delta-v budget 9.5 km/s (let's ignore the atmospheric inefficiencies) the mass of the methane version is a 72% of the one using kerosene. You can use a smaller total cryogenic volume for the tanks!
BTW. They use natural gas instead of pure methane. The only reason for kerosene use was a better supply chain. Nowadays, natural gas is widely available, so there is no reason not to change.
> <
> > In aviation, synthetic fuels are the best solution, unless it is necessary to pre-cool the air in the engine (Skylon).
> > There is only one application where hydrogen should be used - modern airships. Unfortunately, people prefer to waste helium.

piątek, 6 sierpnia 2021 o 18:29:20 UTC+2 Stefan Monnier napisał(a):
> > It is not a reason to weaken market forces even more.
> > Free market happens. The size of the fruit and the amount of nectar are
> > determined by the biological free market, where different species
> > collaborate spontaneously. Eating fruit and drinking nectar is
> > a business transaction.
> That is an illusion.
>
> The free market is based on the notion of "cost". The cost of lives,
> the cost of ecological impact, the cost of trauma, etc... these aren't
> inherently quantified, so your "free market" necessarily needs to be
> built on top of very subjective and politically motivated choices (and
> often enforced by the threat of retaliation).
The free market is based on the notion of voluntary transactions.
Every valuation is totally subjective, there is no theory of objective value. They are subjective so they can be different.
That is the reason transactions happens: valuations of goods are higher for every side after transaction.
The market mechanism sets the price at a level that maximizes the value of the transaction. In this way, we can universally maximize subjective value gains. Whenever something interferes with this mechanism, the performance is compromised. The problem is monopoly, but a monopolist cannot force a customer to make a transaction, so even then the system can be quite efficient..

> It doesn't "just happen" any more than war "just happens".
Yes, war is just going on. War is not something universally wrong: men have to prove their genetic worth, better organizations have to overcome the weak, etc. War was necessary for progress. The struggle for resources is the destiny of every living organism.
>
> Stefan