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the future of fuel?
November 13, 2009 8:42 AM   Subscribe

Using photosynthesis to power hydrogen production
Researchers have found that if they insert platinum nanoclusters into the photosynthetic machinery of bacteria, one acre could produce an amount of hydrogen equivalent to 79 gallons of gas per day.

of course, "there's still the challenge of delivery," but if you're worried about how we'll fuel the planet, "further modification of the basic approach may make the hydrogen economy look relatively practical."
posted by kliuless (37 comments total) 6 users marked this as a favorite

 
How about a nanocluster of platinum up your chute, e. coli? Back to work!
posted by No Robots at 9:00 AM on November 13, 2009 [6 favorites]


Pretty cool how they hijack the bacteria's photosynthesis process to make it produce hydrogen. A lot of practical engineering questions immediately jump to mind though:

How will they get these platinum nanoclusters (or hydrogenase enzymes) into precise locations in trillions of individual bacteria? Genetic modification? Custom viruses? Its a big problem and would need to be done efficiently for this to be feasible.

What do the bacteria eat? How does this offset their hydrogen production?

How will the minute amounts of Hydrogen floating up off trillions of bacteria spread out over an acre be collected? Big greenhouse roof leading to a compressor (can you say explosion hazard)? Where can these farms be put? Deserts? Out at sea?

It'd be awesome if they could get this working on a large scale. Even a mid sized pilot plant would be cool.
posted by no_moniker at 9:17 AM on November 13, 2009


So, for the USA, at 380 million gallons of gasoline per day, that would be 4.8 million acres
of production, or about 7500 square miles.
That's more than Connecticut and less than New Jersey (at 5544 and 8700 square miles).
The Nevada Test Site and Nellis Air Force Base are 5400 square miles, combined.

79 gallons of gasoline a day is about 870,000 watt hours. An acre is about 4096 square
meters. Sunlight falling on that acre is about a million watts. In 6 hours, at 15 percent
efficiency, that would be 920,000 watt hours. Then, there's still the challenge of delivery.
posted by the Real Dan at 9:19 AM on November 13, 2009 [9 favorites]


Previously.
posted by ZenMasterThis at 9:21 AM on November 13, 2009


How much platinum would it take to create 7500 square miles of this stuff?
posted by Chocolate Pickle at 9:37 AM on November 13, 2009


"7500 square miles."

Lucky for us, nobody's proposing to replace the entire existing infrastructure with this! Hooray for supplemental and transitional technologies!
posted by majick at 9:43 AM on November 13, 2009 [5 favorites]


TRD Stop using your math to cause problems. We need insanely challenging solutions to problems where simple ones currently exist, because face it - there are a lot of out of work criminal masterminds that manage to get the hero tied up and, instead of shooting him in the head, they put him under an insanely slow and complicated laser death system. pew pew
posted by msbutah at 9:45 AM on November 13, 2009 [2 favorites]


This would be awesome if you could backyard diy. I've got a 1/3rd of an acre and could reserve a 1/4 of that for hydrogen production. Six gallons a day would be 10-15x my daily gasoline need. If we could figure a good way to store hydrogen it would be possible to significantly offset the natural gas needed for heat in the winter; maybe even completely displace it.
posted by Mitheral at 9:56 AM on November 13, 2009 [1 favorite]


platinum nanoclusters

Let me remind you how nano sized particles were shown in late 1940's work to penetrate the blood-brain barrier in apes.
And buckyballs are deadly to fish (again - nervous system)

And this solution somehow has small particles INTO bacteria....what happens when these bacteria die?
posted by rough ashlar at 10:03 AM on November 13, 2009 [2 favorites]


majick: Hooray for supplemental and transitional technologies!

Listen, I hear you, I hear you, and I want to say the same thing so bad. But at the same time, I'm scared that people like the Freeman Dysons of the world will look at this and say "see, I told you technology would solve the problem."

My personal belief is that we need to re-invent our entire relationship with energy: We need to be generating it everywhere we possibly can (opening doors? passing through turnstyles? pressure-activated sensors?) and then using it locally, which requires rethinking devices and generation networks and, well, just about everything.

This to me is a big technology. It's for large-scale production of H2. Only works large-scale. Yes, we still need large-scale even if we rethink everything. But TRD's points all still obtain.

So, majick, I actually agree with you at least in part and in part of my spirit. But I can't share the optimism.
posted by lodurr at 10:09 AM on November 13, 2009


rough_ashlar, this is akin to Bruce Sterling's [et al's] oft-voiced observations that in the near future we may be awash in "buckyjunk" that we can't get rid of or maybe even find.
posted by lodurr at 10:10 AM on November 13, 2009


no_moniker It looks like they talking about essentially growing up a massive amount of this bacteria in a tank like this one and then purifying the operating enzyme out of the critter.

Also, it is awesome when science reporters actually reference the paper their article is based on. Kudos!

To answer your first question, simplified, it looks like they altered the DNA sequence that encodes for Photosystem 1 to give it domains which bind to the platinum catalyst and express the proteins that make it more regularly (for more product per critter) and altered the sequence for cytochrome c6 (an electron transporter) for similar reasons. They then chemically isolated both enzymes and put it in a container with the platinum catalyst before watching how much hydrogen was produced when they shined light on it. Their plan is to spread the isolated enzymes out over a sunny area with platinum and collect the hydrogen in vivo.

Second question: There might be a more cost efficient way to do it on a large scale but this is what they fed them nitrilotriacetic acid (NTA) media

Also, here is their Discussion section where they talk about logistics questions in more depth

"In summary, we have demonstrated a simple 'rewiring' of the electron transport pathway of PSI that permits a productive interface with a self-organized platinum catalyst (Fig. 1). This light-driven catalytic production of hydrogen is both temporally and thermally stable. Simple optimization of this self-organized system leads to rates close to those recently reported by researchers working with synthetically attached catalysts. Additionally, we showed that increasing the temperature to 55 °C increases our rates by a factor of approx15 (Fig. 5c), which considerably exceed the rates of other available methods while retaining the benefit of a self-organizing system. If scaled linearly, a solar collector 1 acre in size with a solution depth of 10 cm operating at 55 °C would be capable of producing hydrogen with an energy yield equivalent to that of 300 litres of gasoline per hectare per day (gross yield, ignoring production separation and distribution energy costs; see Supplementary data). This potential yield is more than an order of magnitude higher than the gross yield in terms of gasoline equivalents of agricultural biomass systems such as corn-based ethanol (5.43 litres per day per hectare), soy based biodiesel (1.42 litres per day per hectare) or projected yields of switchgrass-produced ethanol (12.1 litres per day per hectare). Comparing this fuel production rate to the average available solar radiation at latitudes in the middle of the US, this system is capable of converting approx6% of solar radiation into usable fuel. This system provides a more direct route to fuel production with no need for the harvesting, converting, fermenting and distilling processes involved in conversion of biomass to ethanol. Moreover, other processing and transportation costs would be much lower because the bio–platinum hybrid catalyst is reused through many cycles, unlike in single-use methods such as biomass accumulation. Finally, the fact that our PSI operates with high thermal tolerance suggests that this approach may be viable in non-arable regions with high solar irradiances. This is in contrast to the cultivation of biofuels that may compete directly with agricultural production."
posted by Blasdelb at 10:11 AM on November 13, 2009 [3 favorites]


Mitheral, you could probably generate enough methane with that acreage to significantly offset your winter heating costs, and with less of a storage cost.
posted by lodurr at 10:12 AM on November 13, 2009


what happens when these bacteria die?

I would imagine they'd recover the Pt nanoparticles and put 'em in new bacteria.
posted by ZenMasterThis at 11:06 AM on November 13, 2009


Hey! Platinum doesn't grow on trees!

It still doesn't, right?
posted by double block and bleed at 11:25 AM on November 13, 2009 [1 favorite]


" I'm scared that people like the Freeman Dysons of the world will look at this and say "see, I told you technology would solve the problem."

Personally, I'm scared that people are going to look at this and say "7500 square miles! We're fucked!" Because while technology alone isn't going to solve the problem, neither is pissing in the cornflake bowl of every energy advance that isn't a magic bullet replacement of existing supply.

We NEED transitional technologies, and we need them, like, 20 years ago. Better we do something about energy than nothing, as far as I'm concerned. Am I optimistic about transitional technology outcomes? Honestly, not much. But I'm more optimistic about them than I am about sitting around waiting for someone to retrofit every SUV with a Mister Fusion.
posted by majick at 11:50 AM on November 13, 2009 [1 favorite]


This would be awesome if you could backyard diy. I've got a 1/3rd of an acre and could reserve a 1/4 of that for hydrogen production. Six gallons a day would be 10-15x my daily gasoline need.

Why? You can make biodeisel or ethanol yourself if you want to. Hydrogen is hard to store, and hydrogen cars are not all that common. BMW makes the Hydrogen 7, but you have to liquefy the hydrogen cryogenically. So not only would you need these GMO plants that haven't been invented yet, you would also need some way to freeze it.

On the other hand, home-made biodiesel is actually pretty common and flex-fuel. Making ethanol yourself might be legaly challenging but not that difficult.

There are tons of flex fuel and diesel vehicles available that can run on these home-brew fuels.
posted by delmoi at 11:50 AM on November 13, 2009 [1 favorite]


Actually this youtube video shows a guy making some biodesel with just some jars, buckets, etc. Looks like a meth-lab. Heh.
posted by delmoi at 11:53 AM on November 13, 2009


rough ashlar: Let me remind you how nano sized particles were shown in late 1940's work to penetrate the blood-brain barrier in apes.
And buckyballs are deadly to fish (again - nervous system)

And this solution somehow has small particles INTO bacteria....what happens when these bacteria die?


ZenMasterThis: I would imagine they'd recover the Pt nanoparticles and put 'em in new bacteria.

Live bacteria are uninvolved the Platinum nanoparticles would be put into solution with the two described bacterial enzymes (Photosystem 1 and cytochrome c6) which would be harvested and purified.

However you do bring up an excellent point: The platinum would be entirely reusable, however, if spread at a depth of 5cm this would be 838,860,800 liters of fluid per acre and thus 235,300 kg of Sodium hexachloroplatinate (IV) (Na2[PtCl6]) at their experimental concentration of 0.5mM, which could conceivably do some damage. Incidentally, this would also contain 81,789 kg of platinum per acre which at the current price sells for around $3.5 billion. Whoops
posted by Blasdelb at 11:57 AM on November 13, 2009 [1 favorite]


So, could you get this set up inside a sealed box with just an inlet for water and a filter that only lets out excess O2 and H2? Seems to me that would be a safe enough solution for keeping the dangerous nanoparticles out.

Or are they so small that they can slip through most transparent materials, which you would need for the photosynthesis to occur?

Also, how would this compare to hooking up a solar panel to an electric car? Let's say we do separate comparison based on cost and acreage, since those are different concerns (land is relatively constant in price, cost for batteries, fuel cells, and solar panels change faster and less predictably, but more important for short term adoption). I'm assuming this has the potential to be more efficient, since it's not like the usual electrolysis where you convert electricity into hydrogen. As it's a relatively direct conversion from water to hydrogen, there's less potential for energy loss.
posted by mccarty.tim at 12:26 PM on November 13, 2009


"Why? You can make biodeisel or ethanol yourself if you want to."

Sure, but the efficiency of that method of converting sunlight to fuel appears to be a tiny fraction of the method described here.
posted by pascal at 12:36 PM on November 13, 2009


Personally, I'm scared that people are going to look at this and say "7500 square miles! We're fucked!" Because while technology alone isn't going to solve the problem, neither is pissing in the cornflake bowl of every energy advance that isn't a magic bullet replacement of existing supply.


But what if the technology is piss in the cornflake bowl?
posted by lodurr at 12:55 PM on November 13, 2009


re-invent our entire relationship with energy We need to be generating it everywhere we possibly can (opening doors? passing through turnstyles? pressure-activated sensors?) and then using it locally,

The idea GREAT.

Your examples are not as useful.

Lance Armstrong had peak output of 644 watts, 400 watts sustained.
A normal cyclist - 200 watts.

1 150 watt solar panel - $500. (last time I bought rounding) So for $1000 you have more labor (measured in wattage) for as many hours as you can capture sunshine. Now consider the lack of moving parts with a PV panel and how after 20 years it can still be producing power.



The technocracy effort wanted to make wattage actual money - which would give us a different relationship with energy.
posted by rough ashlar at 1:04 PM on November 13, 2009


So, could you get this set up inside a sealed box with just an inlet for water and a filter that only lets out excess O2 and H2? Seems to me that would be a safe enough solution for keeping the dangerous nanoparticles out.

Getting electrical power from splitting atoms is rather simple and seems safe enough.

Not to mention rules to follow to keep ppl safe.

Yet every year operators of nuke plants are fined for unsafe operation. Last year (or 2 years ago) someone filmed sleeping on the job security guards at a fission plant.

So while it may SEEM 'safe enough', humans have a REALLY bad history of management. And if nano-platiunum is a nasty toxic - with humans track record to date - why take that risk over 79 gallons of gasoline a day per acre?
posted by rough ashlar at 1:10 PM on November 13, 2009 [2 favorites]


some jars, buckets, etc. Looks like a meth-lab.

I use glass jars as cloche. And the 5 gal pails of Sodium Hydroxide solution from the brewpub happened to be outside awaiting me to remove the lids to convert them into storage containers with gamma-lids. (Hint: the maker - freckleface has sales. Just wait for 'em)

Lo and behold the local fuzz shows up and one of the detectives got all kinds of excited. Cuz he thought he'd found a meth lab.
posted by rough ashlar at 1:19 PM on November 13, 2009 [1 favorite]


rough_ashlar, your critique doesn't surprise me. I've gotten it before.

Thing is, I don't think you get what I'm saying: I mean, we need a total rethinking. You're still talking about capturing energy and storing it somewhere. I'm talking about scavenging energy, and using it where it's scavenged.

We do a lot of things that "waste" good kinetic energy. Totally rethinking the way we use energy could mean either not wasting as much kinetic energy, or scavenging it when we do in order to power low-energy devices that we now either power with batteries or plug into the grid (where they use energy that has to be transported a great distance).

In many cases, this will mean using devices that require much less energy than we would otherwise use. So rather than plugging that pressure-sensor into a grid, you make it power itself. You use your shoes or other piezoelectrics to power your bodynet-dependent devices or your ipod. I presume I don't need to mention electric or hybrid cars and the energy reclaimed from braking, but I should mention the energy that could be reclaimed by braking bicycles.

I also understand this is not a near-term solution, or even anything approaching a total solution, but I think it's the mind-set we've got to get ourselves into.

I don't expect to get a positive response to this, by the way. I've been down this road before. I expect to be ridiculed for this idea. That's fine.
posted by lodurr at 2:13 PM on November 13, 2009


It's nice to see innovative research especially in the field of bio-fuels. But I would consider it just a proof of concept. It is very far from a practical solution. For contrast, if you replaced their 1 hectare solar collector with standard photovoltaic solar panels and then used that power to electrolyze water to make hydrogen you would make more than twice as much.

Take a solar panel with 18% efficiency such as the Sunpower 225 (pdf). A 1 hectare area of these panels (8,038 panels) has a rated peak power of 1,808 kW. You can then use the NREL solar calculator to see how much energy you could generate in a year. I selected Fresno, California as the location, entered 1,808 for the DC rating (kW) and left everything else as default. The energy generated for the year is 2,621,767 kWh which averages to 7,183 kWh/day. That energy could be used to produce 184 kg of Hydrogen using a conversion factor of 39 kWh/kg from this NREL report (pdf) on using wind energy to produce hydrogen. 184 kg of Hydrogen is equivalent to about 740 liters of gasoline using this cool calculator. That's quite a bit better than the 300 liters per hectare per day from the bacteria.
posted by Long Way To Go at 2:16 PM on November 13, 2009


How much platinum would it take to create 7500 square miles of this stuff?

ASK GOOGLE RON PAUL!
posted by Balisong at 5:12 PM on November 13, 2009


Sure, but the efficiency of that method of converting sunlight to fuel appears to be a tiny fraction of the method described here.

Well, what about getting solar panels and an electric car? It would be cheaper then the $3.5 billion dollars worth of platinum per acre this method seems to require.

Also I'm pretty sure someone has already come up with a way to convert sunlight and water directly into hydrogen using just a mirror and a catalyst. the one mentioned here uses rust, and this company will sell you one. And there's a wikipedia article on This live test reactor , which is in the 100 thermal kW range.

In other words, while there is obviously a lot of research that needs to be done, if you want to convert sunlight into hydrogen today, you can.
I don't expect to get a positive response to this, by the way. I've been down this road before. I expect to be ridiculed for this idea. That's fine.
Because it's ridiculous. The amount of energy used for things like pressure sensors is tiny, as is the energy you get from opening doors. It would probably take far more energy to make those micro-generators then they would ever extract. And even if you captured all of it it would only reduce CO2 emissions by a tiny percent.
posted by delmoi at 5:31 AM on November 14, 2009


delmoi: You're missing the point -- well, several points.

Of course the amount of energy is "tiny." "Tiny" is relative. You seem to be thinking about putting that energy into the grid. I'm talking about not having to get it from the grid. Energy from the grid has costs in addition to the energy cost: You lost a lot in transmission, for example. And you have to hook the thing up to the grid, which costs in material and effort. So you can't simply say 'it takes more energy to manufacture than they'll extract.' You have to figure out how much the energy costs that's lost in transmission from the central source. There are other savings, too, in terms of things that you wouldn't have to have in this kind of a regime, or things you'd need less of. You wouldn't need to run as much household current around, for example, which means less loss of electricity before it's consumed.

Also, you're cherry-picking examples. Pressure sensors might not be a great example -- though your use of the term "micro-generators" is interesting. The "generator" in this case could easily be a laminate of foams under the pad. I don't know what the production cost or yield is, but that certainly sounds less ridiculous than "generator" with its mechanical connotations. As I've noted, energy scavenging is already done with cars, and it would make sense to do it with bicycles -- in fact, some of the newer hybrid bicycles already do that by capturing energy when coasting downhill and letting you use it on the next uphill.

Incidentally, I've never argued that this is a solution to CO2, and I thought I'd made that perfectly clear but if I haven't then I'll say it again: This is not a solution to CO2 problems. It's a partial solution -- and I've also made clear that I see it as a partial solution -- to energy consumption problems. What I'm looking for is a change in mindset. What I'm looking for is a reduction in waste. This would encourage a reduction in the use of disposable batteries, for example, and less reliance on energy from the grid, which is lossy. In the short run, of course you don't reduce overall transmission loss because the amount of energy transmitted through the grid won't be affected. But if it's part of a general strategy of producing as much energy locally as you can -- building-top wind turbines, rooftop solar, small-scale "geothermal" heat-pumps, etc. -- then you would see an overall reduction on demand, and additional savings on transmission loss because there's less being transmitted in the first place.

One of the biggest problems with energy is that we are fundamentally dependent on the huge, economy-of-scale-driven central generation systems. Aside from tending to create large systems that are vulnerable to widespread catastrophic failures, it also tends to foster the concentration of political and economic power, and so far has fostered reliance on fuel systems that net us economies of scale. We need to understand going forward that these economies of scale have displaced costs, and we need to jettison this "future-discounting" mentality that lets us write off future costs as unimportant because they belong to our grandchildren, not us. Down that road lies the realization that sometimes saving cost (e.g. through the economies of scale yielded by large, centralized power generation) may not be worth the long-term costs or the short-term vulnerability that come along with them.

So we see the grid evolving now to accommodate smaller inputs like wind power, the different types of solar plant, and neighborhood-scale power generation plants. You also see cul-de-sac-scale geothermal heat pump plants that locally produce cold or hot air, depending on the season. That's part of the same kind of thinking: Think small and reduce vulnerability overall. Systems that can support themselves are less vulnerable to systemic failures. Part of that is reducing energy consumption; another part is bringing the energy source as close as possible to the place where it's consumed. If you can cost-effectively make the energy source part of the device that consumes it -- that's likely to be a win all the way around.

And if your answer is "but you can't do that," then I'm sorry -- you haven't understood what I've said. Words like "if" and rhetorical formulations like hypotheticals exist for a reason.
posted by lodurr at 7:59 AM on November 14, 2009


"On the other hand, home-made biodiesel is actually pretty common and flex-fuel. Making ethanol yourself might be legaly challenging but not that difficult. "

Problem is those people aren't growing the corn/potatoes/soybeans/rape seed or whatever to power their fuel plants on a 1/10 of an acre. Stuff like ethanol from corn is approximately break even on fuel out vs inputs in. Rape seed is better, and you'd be burning it in a more efficient diesel engine but it's nothing like what the researchers were getting in hydrogen.
posted by Mitheral at 8:01 AM on November 14, 2009


Related point: Currently, biodiesel can be cost effective on a small scale, but only because it scavenges waste product from the restaurant and prepared-food-production industries. There's a top end to that; it's cost-effective on a small scale until the restauranteurs and food-factory-owners start charging you for their spent oil, then the backyard-brewers will get locked out. And then you are absolutely stuck with the input:output issues that Mitheral raises.

I.e., it's not a long term solution. As a survival strategy -- something to save some operating costs for a few years, if you don't spend too much setting yourself up to support it -- it can make sense case-by-case. But if you're doing it to save money, then you need to be looking at another solution or a way to solve the money problem, 'cuz Joe's Grill isn't going to give you their used lard forever.
posted by lodurr at 8:07 AM on November 14, 2009


mccarty.tim: are [the nanoparticles] so small that they can slip through most transparent materials?

Interesting concept! Although I think nanoparticles are still made of atoms, like most things around here.
posted by sneebler at 8:45 AM on November 14, 2009


Of course the amount of energy is "tiny." "Tiny" is relative. You seem to be thinking about putting that energy into the grid. I'm talking about not having to get it from the grid. Energy from the grid has costs in addition to the energy cost

Except that "the gird" is already going to be running to your house. All you have to do is connect it to the wall socket. Obviously it would be idiotic to run hundreds of miles of wiring just to add a pressure sensor. But if you have a 1-meter solar panel on your roof, that would be much more then the electricity you would need to run these things.

Also, you're cherry-picking examples.

Those are the examples you gave.

It's a partial solution -- and I've also made clear that I see it as a partial solution -- to energy consumption problems.

Consuming less energy means consuming less energy, it doesn't mean wasting kilowatt hours of energy building neato do-dads to save milliwatts.

Mitheral: My point was just responding to the "I wish there was a home DIY version of this" when in fact, there pretty much is. Both for biodeisel and ethanol (which you can use to power cars) and probably for hydrogen directly from sunlight using solar-concentration techniques. Using plants to do this seems pretty over the top, you can crack hydrogen just by concentrating sunlight and using the right catalysts.
posted by delmoi at 2:09 PM on November 14, 2009


> Related point: Currently, biodiesel can be cost effective on a small scale, but only because it scavenges waste product from the restaurant and prepared-food-production industries.

Actually, in the same micro biology for fuel future, they are already harvesting vegetable oils from algae, and using the carbohydrates to make ethanol as well. Biodiesel as it is now is a transitionary step using the waste vegetable oil (most of it is virgin waste vegetable oil, left over from processing grains for other things also), but people are already researching other ways of getting the fuel produced efficiently on a larger scale. And thats the thing, once we crack that nut, we already have the engines and transportation and storage issues taken care of, which is why I have more hope for biodiesel than hydrogen, as we still have a lot of work to go before hydrogen is practical.
posted by mrzarquon at 10:46 PM on November 14, 2009


From solar energy to hydrogen: there's no step two
Researchers have figured out how to directly couple a cheap and simple photovoltaic system to an equally cheap and simple catalyst that can split water, releasing hydrogen that can be used as fuel.
posted by kliuless at 12:34 PM on November 28, 2009


That's awesome. It'd be nice to have a hydrogen generator that didn't rely on a precious metal. Cobalt and zinc are pretty common.
posted by Mitheral at 5:08 PM on November 28, 2009


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