It would make more sense to find or invent a critter that converts sunlight into a nice hydrocarbon liquid fuel. Hydrogen is hard to store.
The photosynthesis route to fuels is unlikely to be practical. Fracking to extract oil and NG works nicely.
-- John Larkin Highland Technology, Inc picosecond timing laser drivers and controllers jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Oh, it works on small scale. Engineering it up to work for centuries or a planetary scale, however, isn't looking hopeful.
Nuclear, wind, hydrogen have scalability. The 'photosynthesis route' has been practiced for millennia, by actual test it certainly IS practical.
e are playing around with photosynthesis, and one of the scheme produces hy drogen gas from water and sunlight - inefficiently, of course. It's years s ince I saw the abstract and I've got no idea where I saw it.
by
e a lot of oil from coal during WW2, and it sounds as if somebody has reviv ed the process to work with biomass rather than coal. The "70%" refers to t he process as a whole, which leaves room for a lot of fudging.
Greenie blogs are having green-gasps over the sly insinuation that the proc ess gobbles CO2 from the air. That would seem both improbable and grossly inefficient. And they wouldn't need methane feedstock, if that were the ca se.
I s'pose their renewable argument is that they're recycling biomass carbon. That's fair. But dubious economics.
nto steam, and seems to be at the bottom end of the region where enough of it is dissociated into hydrogen and oxygen. It sounds more like a process f or making "water gas" which is a mixture of hydrogen and carbon monoxide.
We don't know. Pure water disassociates into H2 and O2. If they've managed to do that with any remarkable efficiency, that in and of itself could be a us eful advancement.
at it didn't actually say anything meaningful.
Of course. But I've often been able to tell quite a lot from such.
ult life. You need to throw in oxygen to make a fuel cell work.
Sure, we all know that, and we all know they're short-lived and impossibly expensive. If 800C steam might allow a cheap, robust catalyst, or some othe r magic, that's still a useful economy compared to Pt or Pd catalyst.
Thanks for the thoughts.
Cheers, James Arthur
Why not just wish for Shmoos?
-- Rick
Done! Coal pulverized finely will burn and run an engine.
Yes, blessed is the word. Next we will be blessed with ever increasing temperatures.
-- Rick
It's not right. If the carbon is oxidized to CO2 that energy came out somewhere. Both the steam reforming and the gas-shift reaction are endothermic, so the energy released by forming CO and/or CO2 is part of the reaction and goes into reducing the amount of energy required.
Currently the only practical alternative to hydrocarbon fuels for autos is electricity. It is still early days for electric cars and they need to be scaled up with better methods of charging and consideration for the unique loading impact on the electrical infrastructure. Even then that doesn't solve the bigger problem, the source of the energy.
-- Rick
Google Baker Electric. They were waking electric cars 100 years ago.
Dan
I found a certain irony in this line from the article:
"This is already happening in Japan ? a country increasingly concerned about its energy policy in the wake of the nuclear disaster at Fukushima."
Given that nuclear power is the obvious source of electricity to be used in the production of hydrogen through electrolysis.
Sylvia.
It's been done. They just don't do it very efficiently or cheaply.
It's obviously practical,since it seems to be the way all the oil reserves were originally created. Of course, that route lays down oil rather more slowly than we dig it up.
But dumping a couple of billion years worth of fossil carbon into the atmosphere as extra CO2 in a century or so creates problems, even if John Larkin is too ignorant to appreciate them.
-- Bill Sloman, Sydney
?
ple are playing around with photosynthesis, and one of the scheme produces hydrogen gas from water and sunlight - inefficiently, of course. It's years since I saw the abstract and I've got no idea where I saw it.
pt, by
ite a lot of oil from coal during WW2, and it sounds as if somebody has rev ived the process to work with biomass rather than coal. The "70%" refers to the process as a whole, which leaves room for a lot of fudging.
ocess
case.
The greenies would have to be remarkably silly to think that the process ad ds any new CO2 capture, beyond the obvious fact that the creation of the bi o-mass starting material did involve gobbling CO2 from the atmosphere. The air that is sucked in to burn part of the biomass to provide the energy tha t is later captured as hydrocarbon fuel will contain some CO2 - not that an y of that will be "captured" by the process.
n.
The economics depends on the price of oil, which in turn depends on whether you can get your hands on it. Germany in WW2 couldn't.
into steam, and seems to be at the bottom end of the region where enough o f it is dissociated into hydrogen and oxygen. It sounds more like a process for making "water gas" which is a mixture of hydrogen and carbon monoxide.
d to
Thermodynamics 101 says that the efficiency is going to be less than 100%. The 70% claimed is remarkably good, and most likely based on a misconceptio n.
that it didn't actually say anything meaningful.
adult life. You need to throw in oxygen to make a fuel cell work.
yThe original NASA fuel cells certainly were. There's been some progress sin ce then.
Catalysis doesn't change the thermodynamics, and it isn't magic. It can mak e a particular reaction path run faster - but it runs faster in both direct ions.
The Fischer-Tropsch process relies on transition metal catalysts - iron, ni ckel and cobalt, all of which form carbonyl compounds with carbon monoxide
- to catalyse the shift from carbon monoxide plus hydrogen to hydrocarbon p lus water.
-- Bill Sloman, Sydney
The energy source isn't a problem - it's hanging up there in the sky every day.
Solar power is currently more expensive than electricity generated by burni ng fossil carbon, but that's because the generating stations don't have to pay the price they ought to for the privilege of dumping CO2 into the atmos phere.
If we upped the volume of our solar generating plant by another factor of t en, the usual economies of scale should halve the capital cost per kilowatt of solar generating capacity, and solar power would be as cheap as regular power is today. Since regular power is going to get more expensive as we h ave to dig deeper and ship further to exploit our dwindling reserves of fos sil carbon, this ought to be a no-brainer, but our resident non-thinker - J ohn Larkin - doesn't get it.
-- Bill Sloman, Sydney
Am 11.05.2015 um 04:09 schrieb Sylvia Else:
Even more irony, it was a hydrogen explosion that lifted the roof in Fukushima.
Here in Germany we have more electricity from wind in the north than we can transport to the south where it's needed. Generating H2 or methane would be an obvious solution.
New High-voltage lanes are a noNoNO!! among the greens, at least not in their own habitat.
regards, Gerhard
At present, solar power isn't expected to pay the cost inherent in its lack of 24/7 availability. It uses the grid as a free battery, which only works while solar power penetration isn't too great.
Add in the cost of energy storage, and that changes the situation considerably.
Sylvia.
That is one of the two main problems with solar energy - the other one being that the best places to get it (such as deserts) are far from where it is needed.
Both these problems could be solved by using solar energy to electrolyse water and produce hydrogen - or perhaps even more practically, to combine water and carbon dioxide into ethanol. The result is energy in a form that can be physically transported to where it is needed, and it doesn't matter that production is inefficient or can only be done during daylight hours.
That was the first engine of Rudolf Diesel.
-- -TV
Down under, you probably have more of a problem with this than we do, here, as there are more degrees of longitude available (without requiring an oceanic cable to move the electrons to someplace with "current" demand) along with larger population centers.
I think if the panels were more affordable (and effective), you'd see other (less conventional) storage mechanisms come into play (no doubt inefficient but being able to recover 50% is better than being able to recover *0%*!)
The problem (in the US) is that energy is pretty *cheap*. So, very few incentives to conserve, store, recover, etc. E.g., most swimming pools, here, sit idle in winter months (folks too afraid to get a chill... I guess they've never been in the ocean! :> ) whereas they could be used for closed-loop, water sourced heat pumps relatively easily (more so than a ground sourced unit!)
You haven't been paying attention. Thermal solar can heat up a big pool of molten salts - big enough that it can stay hot overnight - and the steam tu rbines that convert that heat into electric power can run all night.
Thermal solar - by storing the energy as heat before converting it to elect ricity - offers remarkably cheap energy storage.
Some goof wrote a dimwitted article in Chemistry in Australia claiming the generating seven times as much energy as it took to build the solar plant i n the first place wasn't good enough to sustain society as we know it, and made the same half-baked claim about the cost of energy storage - making it clear that he thought that storing energy before your turned it into elect ricity didn't change the economics.
When I wrote a letter ot the editor rubbishing his claims - including that one - he still didn't get it.
-- Bill Sloman, Sydney
lack > > of 24/7 availability. It uses the grid as a free battery, which on ly works > > while solar power penetration isn't too great.
e,
Australia isn't much smaller than the USA - 7.692,024 km^2 versus 9,162,968 km^2 and it's probably more urbanised, in that most of the population lives in t he larger cities.
Building enough thermal solar tower generators with molten salt thermal ene rgy storage to cover overnight electricity demand would not be difficult, t hough it would be expensive - this sort of system needs to be big to make t he insulated tanks for the molten salt big enough to have a long thermal ti me constant.
If we built enough of them to hit the economies of scale, it would probably be a cheaper way to generate our electricity than burning fossil carbon, b ut that would be a huge investment, quite large enough to scare the current government out of what few wits it has.
er
nt
For the overnight generation, thermal solar towers which can store lots of energy cheaply as a big pool of molten salt, provide a much cheaper energy storage mechanism than pumped water and pumped air storage, where you have to pay for the extra pump/generators sets, and the inevitable losses on ea ch conversion.
Bill Sloman, Sydney
It's not land mass but, rather, portion of day in which power can be harvested from the sun (and moved around to places that can use it without needing to *store* it). E.g., power can be generated in CA while the sun is setting in ME (so, Mainers can *use* that power instead of CA having to "bank it" -- meeting a real *need*, NOW, is more efficient than trying to store it for a *future* need!).
We also have ~15-20 times the population -- with 15-20 times the energy demands.
I don't believe large scale installations are the solution. They are too capitol intensive. Likewise, small "per home" installations put too big an adoption burden on the homeowners.
The real solution is to use the sun in other ways beyond just fossil fuels, solar electric, etc.
E.g., here (desert southwest), it would be relatively easy to design a home that had zero energy footprint. Passive solar to heat in the winter, earth berming to reduce the cooling load in the summer (by far our biggest energy consumption). Remove the ACbrrr as a power hog and peak (per user) power demands drop dramatically.
Changing lifestyle would allow more effective use of solar hot water heating (e.g., take showers in the evening instead of morning; tell dishwasher to delay start until later in the day; etc.).
Much commuting is wasted. How many people *really* need top be
*at* a workplace, nowadays? (of course, high speed -- not what is currently offered by the monopolies -- network services would make this a lot more practical! "Video conference?" No problem...)Do you really *need* to go to the grocery store? Wouldn't it be more efficient for the store to deliver your foodstuffs in it's "daily run" through your neighborhood? (A previous neighbor used to have groceries delivered -- undoubtedly expensive as it was a "special trip" for the grocer; would have been much cheaper if they were also delivering to a few other homes in the block!)
I think we probably drive ~20 miles/week for "maintenance" purposes (groceries, fuel, other supplies, etc.) The other ~5K/year are for "entertainment"/activities.
(Personally, I would love to have something *like* a Segway for the few times when I need to run to the autoparts store *while* the car is "in pieces"; carrying a battery home while walking is just not fun. And, seems highly wasteful to make a "special trip" -- by car -- for something like that)
It is pretty commonplace for folks to use passive solar to heat their pools, here. Not uncommon for the water temperature to exceed 100F. Those same pools could also be exploited to help *cool* the house interiors (transfering heat from the home interior to the thermal mass of the water). And, heat them in the Winter (two neighbors have air sourced heat pumps -- yet one has a pool that would be more effective!)
The pools are already *there* (and desirable) -- for other reasons (e.g., recreation). What *other* use would "molten salt" find?
Until people take a wholistic approach to their environment and energy needs/resources, you'll end up with inefficiencies that are *tolerable* because energy *is* so inexpensive! (e.g., with gasoline prices down at $2, folks have already started buying big gas guzzlers, again. Then, they'll cry when prices INEVITABLY creep back to the $4, $5 range. "Did you *really* think those low prices were here to stay?" Gas *used* to be $0.19 when I was a kid. How many bad plans were made assuming
*that* would remain the case?? [I'd actually like to play with a stirling engine on a parabolic mirror to see how effective that would be for "modest" electrical loads]
That one is Japanese engineering technology being sold into the UK.
The hydrogen powered motorbike I saw in London a few years back was also very impressive as a feat of design engineering. The "green" energy event in Trafalgar square was somewhat spoilt for me by the presence of half a dozen smelly noisy diesel generator sets on tickover providing mains power to the exhibition stands whilst more than a dozen high power brand new shiny hydrogen fuel cell systems stood idle.
The only fuel cells actually being run in anger were educational toys!
-- Regards, Martin Brown
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