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MIT Envisions DIY Solar Cells Made From Grass Clippings

samzenpus posted more than 2 years ago | from the growing-power dept.

Power 126

Zothecula writes "Research scientist Andreas Mershin has a dream to bring inexpensive solar power to the masses, especially those in developing countries. After years of research, he and his team at MIT's Center for Bits and Atoms, along with University of Tennessee biochemist Barry Bruce, have worked out a process that extracts functional photosynthetic molecules from common yard and agricultural waste. If all goes well, in a few years it should be possible to gather up a pile of grass clippings, mix it with a blend of cheap chemicals, paint it on your roof and begin producing electricity. Talk about redefining green power plants!"

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126 comments

Adds new import to the phrase "keep off the grass" (4, Interesting)

Barbara, not Barbie (721478) | more than 2 years ago | (#38942897)

Of course, at 0.01% efficiency, you won't be able to tell the difference. Unless, of course, you're into that "other" grass, in which case it's "Oh so kool man! Now I don't have to mow the roof AND get enough power to run a watch one day a year."

Re:Adds new import to the phrase "keep off the gra (4, Insightful)

Tsingi (870990) | more than 2 years ago | (#38942961)

Of course, at 0.01% efficiency, you won't be able to tell the difference. Unless, of course, you're into that "other" grass, in which case it's "Oh so kool man! Now I don't have to mow the roof AND get enough power to run a watch one day a year."

OK miss negative Nancy. It's 0.1% and it's still experimental. I think it's awesome that they can do that.

Re:Adds new import to the phrase "keep off the gra (1, Insightful)

wagnerrp (1305589) | more than 2 years ago | (#38943275)

OK Miss Positive Pauline. Photosynthesis in plants only operates at a couple percent efficiency in the first place. Commercially available thermal and photovoltaic systems are already several times that, but still need immense tracts of land to make a significant dent in our electrical demands.

Re:Adds new import to the phrase "keep off the gra (2)

ciderbrew (1860166) | more than 2 years ago | (#38943463)

1) reduce electrical demands 2) use more land 3) ...

Re:Adds new import to the phrase "keep off the gra (2)

cobrausn (1915176) | more than 2 years ago | (#38943859)

1) reduce electrical demands

Yeah, good luck with that.

Re:Adds new import to the phrase "keep off the gra (0)

icebraining (1313345) | more than 2 years ago | (#38944311)

Actually, it's very easy if a government wants to; they just need to tax it heavily.

Re:Adds new import to the phrase "keep off the gra (1)

cobrausn (1915176) | more than 2 years ago | (#38945673)

Again, good luck with that.

See how long you stay in office after you tax energy usage to the point where the average American starts to take notice. And how do you plan on taxing the rest of the developing world when they don't follow suit? Once they realize they like having life with reliable electricity and all the conveniences and comforts of modern living, my guess is you will have a hard time getting them to reduce their energy demands. It's only a matter of time.

Re:Adds new import to the phrase "keep off the gra (0)

Anonymous Coward | more than 2 years ago | (#38946067)

...and then get themselves over-thrown! why not just let the natural market forces drive the push toward efficiency? as electricity gets more expensive, people will try to use less and buy devices that use less.

Re:Adds new import to the phrase "keep off the gra (1)

Tyrannosaur (2485772) | more than 2 years ago | (#38946003)

I would just say more land. It's amazing what huge tracts of land can do.

Re:Adds new import to the phrase "keep off the gra (4, Informative)

Khyber (864651) | more than 2 years ago | (#38944185)

"Photosynthesis in plants only operates at a couple percent efficiency in the first place."

WRONG!!! Try 9% under regular sunlight, and ~15% under LED lighting.

Oh, did I neglect to mention photobiology/optoelectronic R&D is my job?

Re:Adds new import to the phrase "keep off the gra (-1)

Brian Feldman (350) | more than 2 years ago | (#38944461)

Ignoring the fact that there's no such thing as "regular sunlight" due to variances in season/geography: LED lights can come in any of an enormous variety of spectra, be combined, or not even be a single wavelength at all and be an ultraviolet light with an LED UV emitter (white LEDs). What meaningless numbers and broad statements...

Re:Adds new import to the phrase "keep off the gra (0)

Anonymous Coward | more than 2 years ago | (#38944535)

Pedantic troll is pedantic troll

Re:Adds new import to the phrase "keep off the gra (3, Informative)

feedayeen (1322473) | more than 2 years ago | (#38944647)

Ignoring the fact that there's no such thing as "regular sunlight" due to variances in season/geography: LED lights can come in any of an enormous variety of spectra, be combined, or not even be a single wavelength at all and be an ultraviolet light with an LED UV emitter (white LEDs). What meaningless numbers and broad statements...

Translations since you want to be an obnoxious dick.

"Regular Sunlight" - The spectrum of light emitted by the sun which makes it though to the surface under normal atmospheric conditions consisting of a distribution of all wavelengths within the visible spectrum along with limited radiation outside this range which have near negligible effect on photosynthesis.

"LED lighting" - Controlled, artificial lighting used in laboratories which have been designed to produce a desired light spectrum. This is used to produce the ideal lighting conditions with the highest achievable efficiency (most likely a combination of red and violet LEDs).

"Efficiency" - The ratio of energy put into a system to the ratio of energy put out

Re:Adds new import to the phrase "keep off the gra (0)

Anonymous Coward | more than 2 years ago | (#38944537)

And what is that efficiency when the plant is dead?

Secondly, there is no problem with painting your solar panels from whatever crap you want. The problem has been always trying to get the power from each cell to the grid. This requires wires. This is where the problem starts.

Finally, not to sound smug, but 9% or 15% is all shit. With thermal panels you can get near 100% conversion to heat and you can heat your place or your water. Heck, you can heat a rock with solar stove and cook a meal. To downgrade that efficiency and utility so you can make a few "sparky sparky" at 10% and 10x the cost is retarded.

And as I wrote elsewhere, the capital costs of a freaking nuclear or hydroelectric or even coal power plant are smaller than capital costs of batteries trying to store the power that station can produce overnight.

Re:Adds new import to the phrase "keep off the gra (0)

Anonymous Coward | more than 2 years ago | (#38944545)

And where does the electricty for the LED lighting come from? 15% efficiency is inefficient to drive this perpetual motion machine.

Re:Adds new import to the phrase "keep off the gra (3, Funny)

NemoinSpace (1118137) | more than 2 years ago | (#38944955)

Oh, did I neglect to mention photobiology/optoelectronic R&D is my job?

Yes, you did. Then you realize this process the article describes is about as sensible as manufacturing vitamin D by extracting it from Humans standing in sunlight (regular or otherwise).
I'll take your figures for the efficiency since your the expert, but - The article quotes "electrical power density of 81uW/cm2". If they doubled the efficiency it still wouldn't be worth it.
Did I neglect to mention I can do math?

Re:Adds new import to the phrase "keep off the gra (0)

Anonymous Coward | more than 2 years ago | (#38945301)

It's posts like this one that make me wish for a +1 Bazinga! mod.

Re:Adds new import to the phrase "keep off the gra (4, Informative)

radtea (464814) | more than 2 years ago | (#38945225)

WRONG!!! Try 9% under regular sunlight, and ~15% under LED lighting.

The GP is correct for the typical case of real plants: http://en.wikipedia.org/wiki/Photosynthetic_efficiency [wikipedia.org]

The typical case is pretty low efficiency, the best case (sugarcane) is lower than your 9% number.

Oh, and did I neglect to mention your .sig is obnoxious? I'm guessing you're an undergrad with a bottle-washing role.

Re:Adds new import to the phrase "keep off the gra (0)

Anonymous Coward | more than 2 years ago | (#38945611)

Bazinga!

Re:Adds new import to the phrase "keep off the gra (1)

Khyber (864651) | more than 2 years ago | (#38946277)

"Oh, and did I neglect to mention your .sig is obnoxious? I'm guessing you're an undergrad with a bottle-washing role."

Research director, actually. Good job assuming when you're clueless.

Re:Adds new import to the phrase "keep off the gra (0)

Anonymous Coward | more than 2 years ago | (#38945303)

9% is still very inefficient. I'm pretty sure that's what Khyber meant.

Re:Adds new import to the phrase "keep off the gra (1)

wagnerrp (1305589) | more than 2 years ago | (#38945403)

You might get significantly higher efficiency off of a monochromatic light source at 700nm, but then were talking about something to capture energy from the Sun, so that bit of data is irrelevant. Your average plant is going to convert 9% or so of its captured light into chemical storage, but then nearly half of that gets reused in its own metabolic processes.

Now that 5%-9% value is the important one to be concerned about when you're going to reprocess that biomass directly into energy. In this case, they break down that biomass, extract the PS1 electron pump, and use a Zinc-oxide framework to capture those electrons, and feed it to a harvesting circuit. Now there are three problems with this setup. First, you're going to be limited in the amount of projected surface area you can cover in the protein complex, and thus the percentage of light you can collect, of course this same restriction exists in plants. Second, proteins break down. In a plant, you've got the various metabolic processes available to construct and replace damaged sections of photo-active surface, while in this you need to get up on your roof and replace the surface.

Third and most important, plants use a phospholipid bilayer to separate two volumes, across which the PS1 electron pump operates. This layer is nearly impermeable to ions, allowing those ionic gradients built up by the pumps to drive further machinery for work. In contrast, this PS1-derived solar cell just relies on happy chance that the pump is oriented properly, and the electrons are not just pumped back out into the electrolytic medium and recombined. That is the primary reason this is only able to capture 0.1% of the available light, rather than the nearly 30% that stage is capable of in plants. Such recombination has always been the limiting factor of all such dye-sensitive solar cells.

Re:Adds new import to the phrase "keep off the gra (3, Informative)

ArsonSmith (13997) | more than 2 years ago | (#38943379)

They figure with $30-40 million in government grants they may be able to double that.

hopeless? (1)

goombah99 (560566) | more than 2 years ago | (#38946647)

the lifespan of well treated chlorphyll bearing protein is about 30 minutes. the chlorphyl molecule resides in an equistly (qunatum) tuned environment to achieve it's meager effieiciency in cells. I strongly doubt anything recovered form grass shavings will be of lasting use.

Re:Adds new import to the phrase "keep off the gra (2)

brokenbeaker (267889) | more than 2 years ago | (#38944415)

If you have no electricity to start with, even a little is a huge improvement. This is not meant for industrialized places.

Re:Adds new import to the phrase "keep off the gra (1)

JoeMerchant (803320) | more than 2 years ago | (#38945313)

(81 microwatts) per (square centimeter) = 0.0752514624 watts per (square foot)

75 watts from 1000 square feet of collecting area? I think there are better uses for the zinc and tin making the substrate.

So, in a few years? (5, Funny)

jcreus (2547928) | more than 2 years ago | (#38942903)

Re:So, in a few years? (2)

Quiet_Desperation (858215) | more than 2 years ago | (#38945707)

Actually, it needs to be a chart of how long it is until the "awesome technological breakthrough!" in question is never heard about again. It ranges from 1 to 6 months.

I still remember arguing with supposed geeks online years ago about a claim some company was making about delivering 2 Gbps internet to every home in a neighborhood over existing power lines. Yes, 2Gig individually to each home. Some piffle about power lines having infinite bandwidth because they are not inside a shield like a regular cable or... something.

People were tossing all the hoary old quotes at me from people in the past who said everything was invented or heavier than air craft would never fly. I think someone even trotted out the Ben Franklin quote about giving up rights. *shrug* I guess they were a little slow. I tried to argue impedances, Shannon theory, those pesky transformers, and basic EM physics, but to no avail. People *know* *what* *they* *know*, especially when it comes to things they know nothing about.

A few months later the company web site was gone, and early investors were left wondering where their pants went.

Or you could electrocute yourself in the process (4, Informative)

elrous0 (869638) | more than 2 years ago | (#38942929)

in a few years it should be possible to gather up a pile of grass clippings, mix it with a blend of cheap chemicals, paint it on your roof and begin producing electricity.

Just because it's "green" doesn't mean it's safe to let just any yahoo install an electric generator on his hut. Methinks it might be wise to let the village electrician do the installing.

Re:Or you could electrocute yourself in the proces (5, Interesting)

G-News.ch (793321) | more than 2 years ago | (#38942971)

And yet another 10 years later they find that those "cheap chemicals" cause cancer...

Re:Or you could electrocute yourself in the proces (2)

jginspace (678908) | more than 2 years ago | (#38943251)

Just because it's "green" doesn't mean it's safe to let just any yahoo install an electric generator on his hut. Methinks it might be wise to let the village electrician do the installing.

And just to be safe he should wait till it goes dark. Oh wait a minute ...

Re:Or you could electrocute yourself in the proces (2)

ColdWetDog (752185) | more than 2 years ago | (#38943775)

Just because it's "green" doesn't mean it's safe to let just any yahoo install an electric generator on his hut. Methinks it might be wise to let the village electrician do the installing.

Waiting for the Electrician, or someone like him?

Do you call the electrician when you have to replace the batteries in your flashlight?

Re:Or you could electrocute yourself in the proces (1)

neonKow (1239288) | more than 2 years ago | (#38945475)

That's okay. Any yahoo can install an OS, but I've yet to meet a yahoo that doesn't consider him/herself a geek who will try.

Re:Or you could electrocute yourself in the proces (2)

Purist (716624) | more than 2 years ago | (#38945751)

How do you say "Nuttin' don't get done wit'out it don't get done by da union" in Swahili?

Re:Or you could electrocute yourself in the proces (1)

Son of Byrne (1458629) | more than 2 years ago | (#38946527)

Yeah, and other such nonsense like: "Wiring's not a hobby hire a licensed electrician" et al

Heard it before dude and it still annoys me

Concentrated right? (1)

jginspace (678908) | more than 2 years ago | (#38943037)

If all goes well, in a few years it should be possible to gather up a pile of grass clippings, mix it with a blend of cheap chemicals, paint it on your roof and begin producing electricity.

I assume the method concentrates these photosynthetic molecules. If so you're going to need several roof-areas-worth of grass clippings. And then you have the old problem of taking arable land and forcing food prices up. If this produces much with the grass clippings from an average suburban house then I'm amazed - and will it last through the winter?

Re:Concentrated right? (4, Interesting)

timeOday (582209) | more than 2 years ago | (#38943117)

I wonder if you wouldn't get a lot more bang from your compost heap by putting a tarp over it and collecting the gasses rising out of it to burn?

Re:Concentrated right? (2)

GameboyRMH (1153867) | more than 2 years ago | (#38943795)

Definitely better for the environment at these efficiency numbers. Better to burn methane than to let it escape.

Re:Concentrated right? (1)

Khyber (864651) | more than 2 years ago | (#38944195)

Compost heap big enough could generate enough heat to run a Stirling Engine.

Re:Concentrated right? (3, Interesting)

vlm (69642) | more than 2 years ago | (#38943145)

and will it last through the winter?

If its made out of grass clippings, then by April or May at worst I'll have enough to make another cell-roof.

One weird issue is if its pitifully 0.1% efficient, it might be more productive overall to simple TDP the collected grass clippings into gasoline and dump it into a generator. Or ferment into ethanol. Just simply burn as biomass?

I think a solar powered electric self growing fence would be pretty cool, at least until it shorts out and starts itself on fire. Which brings up the other idea of a self growing survival tool, a mushroom grown in pitch blackness which when placed in sunlight eventually bursts into flame using self generated photosynthetic electricity.

Efficency (5, Interesting)

vlm (69642) | more than 2 years ago | (#38943043)

From the fine article they're getting 0.1% efficiency right now. In other words, about a thousandth. Conveniently, you get about a KW of light per sq meter. So, you get about one watt per square meter. So I could get about 40 watts at noon off my roof, well, other than that tree being in the way which shades me from the summer sun. That is somewhat more than the naysayers claim (barely enough to run a watch, etc) but is not enough to be useful.

Its unlikely they'll exceed the best plants which have had hundreds of millions of years to optimize their design... so figure 5% or so would be quite an achievement. So in Star Trek miracle land, a KW or two is quite possible off a typical roof. Of course in Star Trek miracle land, you'd have 47% efficient cells thus generating about 40 KW. I donno what I'd do with 40 KW laying around, I guess air condition my entire open air backyard, replace my beer fridge with a supermarket open display case so I don't have to waste time opening the door?

The crack about painting it on is laughable. conductive acid rain and bird poop will short it out. You're still going to need glass/plastic/etc and the cost of that will probably make high efficiency silicon more economical.

Re:Efficency (4, Informative)

wagnerrp (1305589) | more than 2 years ago | (#38943323)

Of course in Star Trek miracle land, you'd have 47% efficient cells thus generating about 40 KW. I donno what I'd do with 40 KW laying around

Sell it back into the power grid for use in high density apartment buildings, and higher density manufacturing industry.

Re:Efficency (1)

Oligonicella (659917) | more than 2 years ago | (#38943843)

At what, a nickel a hundred weight? Get real. Everyone with a lawn will have the produce.

Re:Efficency (2)

wagnerrp (1305589) | more than 2 years ago | (#38944157)

Fine. In Star Trek miracle land, it's already a utopia where we don't use money, so you're just going to freely give that power back into the grid, so it can be transferred to somewhere that will use it.

Re:Efficency (4, Informative)

Dan East (318230) | more than 2 years ago | (#38944293)

That is somewhat more than the naysayers claim (barely enough to run a watch, etc) but is not enough to be useful.

Sorry, but you're off by several orders of magnitude. A wrist watch consumes microwatts of power - around 1 micro watt (Slashdot seems to strip the micro symbol). Thus 40 watts is enough to power 4 million wristwatches.

Seiko makes a watch with an IC powered by only 25 nano watts of power!

Re:Efficency (1)

newcastlejon (1483695) | more than 2 years ago | (#38945337)

(Slashdot seems to strip the micro symbol).

Indeed, along with most other useful non-latin letters.

Try u, as in um and ug. It looks close enough. Alternatively there's the one that's popular in the medical industry - I assume it's because label printers don't do it - mcg.

Re:Efficency (2)

neonKow (1239288) | more than 2 years ago | (#38945519)

You're saying the same thing he is saying...that the naysayers are exagerating when they say a roof of this material can only run a watch.

Re:efficiency - fixed that 4u (0)

Anonymous Coward | more than 2 years ago | (#38946257)

hundreds of blah blah. Evolution is adaptation, not refinement. Stop associating Evolution with Moore's law, dummy. It could be something silly and bam, 90% efficiency. Biology is essentially billions of years worth of quantum-chemical technology R&D. :P

Re:Efficency (0)

Anonymous Coward | more than 2 years ago | (#38946481)

Its unlikely they'll exceed the best plants which have had hundreds of millions of years to optimize their design...

One could wonder if currently existing plants have any benefit in providing more electricity than they currently do. There is no sense in evolving any further if there is no incentive...

QWK (once a week) (1)

smoothnorman (1670542) | more than 2 years ago | (#38943057)

Given the nature of the organic (chemical) bonds involved, i think it's safe to say that you'd be required to "gather up your grass clippings, mix with chemicals, and paint it on your roof" rather frequently to maintain any sort of significant electricity production. That is, the original organism has to turn these structures over fairly often, and so would you. But, (i suppose), given the proper equipment, it wouldn't be too much more terrible than moving the lawn and washing the car once a week... maybe. And besides, the neighbor's camellia bush has always annoyed you anyway, so...

2.5million hectares per GW (annual average) (3, Interesting)

tp1024 (2409684) | more than 2 years ago | (#38943071)

If you need to blanket a whole country with solar cells and still don't have enough power for all people, you shouldn't talk about a drawback. You should talk about it being useless for this purpose.

If you blanket all of Germany with cells of this type, you'll get 13.6 GW on average, assuming perfect and unlimited storage - Germany needs 70GW of electricity. And of course, you'd have to blanket *all* of the country, so you'd have to say goodbye to forests, mountains, lakes, rivers, fields ... or an unblocked view of the sky for that matter.

Re:2.5million hectares per GW (annual average) (0)

Rogerborg (306625) | more than 2 years ago | (#38943189)

<Obligatory>Global warming denialist! Big Oil puppet snake!</Obligatory>

Re:2.5million hectares per GW (annual average) (2)

tmosley (996283) | more than 2 years ago | (#38943363)

So? The first electric light bulb wasn't bright enough to light the entire world, yet here we are, lit up like the 4th of July all year long.

It is only a matter of improving efficiency. If this material is so cheap, it can be used as a paint to reduce electricity requirements by 5%. Maybe with further tweaks that can turn into 10 or 15%. No-one said this has to be the only method in use. It's just a cheap one that uses abundant materials. A proof of principle, if nothing else.

Re:2.5million hectares per GW (annual average) (1, Informative)

Oligonicella (659917) | more than 2 years ago | (#38943967)

"It is only a matter of improving efficiency."

No, it's not. It's a matter of how much the efficiency can be improved. In no way will this ever become a realistic electrical source. By its very nature it cannot produce enough.

"If this material is so cheap, it can be used as a paint to reduce electricity requirements by 5%."

No, that presumes you can stack paint. You can't. It's the area that counts, not how much paint you have.

As figured out by someone elsewhere on this topic, an entire house roof will light one dim bulb for a day. I seriously doubt this even approaches 5% of your use.

Re:2.5million hectares per GW (annual average) (1)

NatasRevol (731260) | more than 2 years ago | (#38943589)

If they get it to 1% efficiency, they'll have 136GW in Germany.

So only half of the country will need to be covered in rotting grass.

Re:2.5million hectares per GW (annual average) (2)

Beelzebud (1361137) | more than 2 years ago | (#38943745)

Yeah I agree. They did not get 110% efficiency on their first try, so it's time to pack it in and give up.

Re:2.5million hectares per GW (annual average) (0)

Anonymous Coward | more than 2 years ago | (#38945677)

"If you need to blanket a whole country with solar cells..."

You don't need to.

"If you blanket all of Germany with cells of this type"

"This type" is experimental (as you might know) so you don't need to.

With solar cells currently in use it would suffice to cover every roof in Germany to have enough power for all Germans.

Grass on the roof (0)

Anonymous Coward | more than 2 years ago | (#38943167)

Having grass on the roof adds a whole new meaning to getting high.

Oh, please... (5, Informative)

Jiro (131519) | more than 2 years ago | (#38943207)

Yes, it takes grass clippings. Also "zinc oxide nanowires interspersed with titanium dioxide sponges".

Claiming that this is a solar cell made from grass clippings is like the Rubik's cube solver built from Lego (one component of which was a computer; the computer's not built from Lego). If you want a car analogy, it's like claiming your car is made from glass (since it has glass in the windows).

Re:Oh, please... (1)

mykepredko (40154) | more than 2 years ago | (#38943371)

I thought exactly that when I RTFA.

I don't know if zinc oxide nanowires and titanium dioxide sponges can be manufactured for pennies per square metre (which is what will be required to use this technology in developing countries) - but I suspect that along with improving the output efficiency of the solar cells, there is a lot of work to do to improve the cost efficiency as well.

It all comes down to marketing hype.

myke

Re:Oh, please... (1)

wiedzmin (1269816) | more than 2 years ago | (#38943849)

Reminds me of some cooky article I saw a few months ago about someone "making glasses from recycled human hair", which turned out to be them taking human hair and adding it into the plastic from which the frames were being molded anyways...

Re:Oh, please... (1)

radtea (464814) | more than 2 years ago | (#38945349)

If you want a car analogy, it's like claiming your car is made from glass (since it has glass in the windows)

Sure, but this kind of bullshit is routine in what passes for the "science and technology" press.

We have "quantum teleportation" in which nothing more ontologically robust than the quantum state is "teleported".

We have "downloading 3D objects" in which nothing but a perfectly ordinary binary file is downloaded.

We have "controlling a with just your mind" in which "your mind" apparently includes a few hundred thousand dollars worth of extremely complex gear.

And so on.

Apparently "science" journalists are too stupid to realize how stupid this kind of thing makes them look. Unfortunately most of their audience seems not to care, but would rather repeat cool-sounding but meaningless words than learn anything about actual science and technology.

Re:Oh, please... (1)

Quiet_Desperation (858215) | more than 2 years ago | (#38945903)

Unfortunately most of their audience seems not to care, but would rather repeat cool-sounding but meaningless words than learn anything about actual science and technology.

I virtualize 3D crowdfunded clicktivism in the social cloud ecosystem via the hypernet with my OLED phablet!

MOAR. SQAR. METRES! (3, Informative)

h4x354x0r (1367733) | more than 2 years ago | (#38943209)

The continental US receives about 192,000 Exojoules of solar irradiance per year. We currently use about 91 Exojoules of energy from all sources. At .1% efficiency, and calculating extra for peak needs, intermittency, and transmission losses, we would have to cover nearly 100% of our continental land mass with this stuff to replace our current energy sources. Seems to me like smoking the other kind of grass really is a better deal.

Re:MOAR. SQAR. METRES! (5, Insightful)

tmosley (996283) | more than 2 years ago | (#38943403)

Yes, and we would have needed an airport every 50 meters if the plane built by the Wright Bros was really the best that could ever be built.

The first step is rarely the last one.

utter un-sightful bullshit (1)

iggymanz (596061) | more than 2 years ago | (#38943943)

The Wright Flyer III, built within TWO YEARS of their first flight, had a range of 25 miles! As an engineer, I can tell you this articles technique is useless, even if ten times the efficiency process would not be worthwhile.

Re:utter un-sightful bullshit (5, Insightful)

circletimessquare (444983) | more than 2 years ago | (#38944207)

what is useless is to denigrate basic research

to do that, as an engineer, you should be ashamed of yourself

the common joe might bloviate ignorantly about how silly basic research is, and confuse basic research claims and evidence with the end-all be-all of claims and evidence, but you really should know better

yet, looking at other comments here on slashdot, it seems the intelligence to appreciate basic research has indeed been replaced by this kind of ignorant jump to judgment

you know what? paint on grass clippings does sound silly. but i thought we had a scientific bent here, and this would be EXCITING

imagine that

so shame on you slashdot

Re:utter un-sightful bullshit (1)

iggymanz (596061) | more than 2 years ago | (#38944525)

I do not denigrate basic research that has even the remotest hope of producing something useful. I denigrate that which is provably a waste of time and money based on known workings of this universe.

Re:utter un-sightful bullshit (2)

circletimessquare (444983) | more than 2 years ago | (#38944897)

you:

"what are you doing?"

wright brothers:

"we are assembling basic materials into an interesting shape"

you:

"that's not very descriptive, what is the goal of your efforts here?"

wright brothers:

"ok, you asked, but we don't say what we are trying to do because we get laughed at by simpletons. since you are an engineer, and have some appreciation of what mankind can do with his imagination, we'll level with you: we hope to build flying machines that someday will whisk people around the globe, used more than railroads"

you:

"more than railroads! I denigrate that which is provably a waste of time and money based on known workings of this universe."

you're a dolt. stick to engineering and implementing technologies other people create, and stop showing off your colossal lack of imagination

actually, engineer is not a term you deserve. a plumber fixes toilets. an engineer designs new uses for technology, creatively. a scientist invents new technology. based on your lack of imagination and lack of appreciation for mankind's historical achievements in the striving for new technology, you rank somewhere below plumber. at least a plumber has to get creative now and then

seriously: you are on the wrong website

Re:MOAR. SQAR. METRES! (1)

Oligonicella (659917) | more than 2 years ago | (#38944045)

The Wright Brothers built their plane in a bicycle shop by hand. These guys aren't in the garage, they're already using state of the art lab technologies. Bad comparison.

Re:MOAR. SQAR. METRES! (1)

circletimessquare (444983) | more than 2 years ago | (#38944225)

no, good comparison. the methods used to arrive at INITIAL results doesn't change the fact we are talking about INITIAL results

what is with the anti-basic research prejudice on slashdot of all places?

Re:MOAR. SQAR. METRES! (1)

cyberchondriac (456626) | more than 2 years ago | (#38945379)

I haven't posted anything on this thread until now, but I'll put forth a thought: I think it's particular to solar tech. We've been told about the next new solar breakthrough so many times now over the decades, but most deliveries have fallen short of the claims; we're just jaded. While solar tech has certainly improved, we've yet to see the kind of results expected (or hoped for) some time ago, kinda like, it's 2012, where are our Jetsons-eque flying cars?
The history of science is chock full of naysayers, even educated ones, who really should've known better [rinkworks.com], but once in a while, I imagine some naysayers are right, too.

Re:MOAR. SQAR. METRES! (1)

h4x354x0r (1367733) | more than 2 years ago | (#38944367)

Conventional solar panels are averaging about 15% efficiency; 150 times more efficient than this new source. That's an awfully big gap to make up, and I don't believe the efficiency of conventional panels is going to stop so this other technique can catch up. With conventional solar panels, we'd need to cover nearly 5% of our landmass with them to completely replace all other sources of energy. With this new technique, 100%+. There's a difference in feasibility. I'm not totally knocking the idea; if you could get the grass clippings panels up to even 1.5% efficiency, and the cost down to 10% or less compared to conventional panels, and you've got the space to put it... why not? It will still do the job just fine. But I doubt this new technique can comonly meet all 3 of these criteria simultaneously. It will have very limited applications.

Re:MOAR. SQAR. METRES! (1)

tmosley (996283) | more than 2 years ago | (#38944813)

Yes, and it would have been ludicrous to think that you could create a worldwide system for travel and shipping using the Wright Bros design, yet here we are.

Even if this proves to be unworkable, it advances our knowledge. If grass clippings aren't good enough, perhaps we genetically engineer some bug to make the right mix of materials for us to give us a 5% efficient cell that costs ten cents a watt. Combine that with other advances, and maybe we get a 50% efficient cell for 1 cent a watt. Who's to say? The point is that this is a first step in a new direction. Probably not the last.

Re:MOAR. SQAR. METRES! (1)

h4x354x0r (1367733) | more than 2 years ago | (#38946299)

I totally agree this advances knowledge and technology in a general sense, and that's a Good Thing. Just because this isn't feasible as-is, it might still become an important building block for something that is. I certainly still support continuing to spend money on this line of research! So despite the un-Slashdot-ish nature of saying this... point well made. On the point of the viability of one-offs, I'll point out there is one other very important aspect of plant life that we should be trying harder to harness / emulate: energy conservation.

If it sounds too good to be true, it probably is. (1)

gweihir (88907) | more than 2 years ago | (#38943347)

Would not surprise me at all. I suspect somebody is looking for grant money, and "a few years" will turn out to be very, very long, possibly infinitely long.

Re:If it sounds too good to be true, it probably i (2)

jamstar7 (694492) | more than 2 years ago | (#38945619)

The good news is, we're only 20 years away from fusion power.

Okay, stupid question time (1)

Anonymous Coward | more than 2 years ago | (#38943627)

How much energy would I generate simply by cutting the same amount of grass and burning the clippings? We are talking carbon neutral since the grass continues to grow.

This seems as good of a solution as the one being proposed.

Re:Okay, stupid question time (1)

wiedzmin (1269816) | more than 2 years ago | (#38944009)

Carbon neutral doesn't mean that it continues to grow, it means that whatever carbon is released from burning it, was originally absorbed from the atmosphere. Burning down rainforests is also carbon neutral, if you think about it, although a lot less popular amongst all the soccer-mom movements...

But to answer you question, it appears [remarkable.com] that leaves have approximately 61.5% of the calorific energy value of coal, so I am assuming that grass would be similar.

Re:Okay, stupid question time (1)

Oligonicella (659917) | more than 2 years ago | (#38944145)

It would be less as some grasses use silicon for stiffeners and defense. That's why razor-grass cuts the shit out of your ankles, it's edges really are glass - ish.

Consider density too. Even a dense bamboo is pretty light.

Yea right (0)

Anonymous Coward | more than 2 years ago | (#38943683)

I have a sneaking suspicion that whoever wrote the summary has never applied for a building permit before.

Here's hopin! (2)

bobbied (2522392) | more than 2 years ago | (#38943853)

Well, Cheaper solar cells would be nice no matter how they are made but this is going to have to improve it's effeciency by more than 10X's or it won't be worth the trouble. Current solar cells approach 200x (or more) of this efficency and they are not able to acheive ROI's high enough to be cost effective. They need to drive the cost factor down to where the cost/watt is at least on par with current cells. Somehow, I don't think that using grass will be cheap enough given that current cell designs use things like sand as raw materials..

Everybody needs to remember.... It's cost per watt that will drive this industry. Make it so the cost/watt is at or below the cost of buying power off the grid and the stuff will sell like hotcakes. Until then, it will be a small market.

Maybe there's a simpler solution (1)

aglider (2435074) | more than 2 years ago | (#38943977)

Let's stop polluting the world and let the natural photosynthesis do the job.

Fraud - be careful (5, Interesting)

Anonymous Coward | more than 2 years ago | (#38944069)

A modified type of dye sensitized solar cell, nothing new.
https://en.wikipedia.org/wiki/Dye-sensitized_solar_cell [wikipedia.org]

You can easily make those at home: Take a piece of conductive glass, coat it with titanium dioxide (yes, exactly the pigment used for white paint, I tried the commercial pigments myself), dip it into a dye (yes, I tried chlorophyll, these things were known at least 15 years ago, this is when I did it), put on a second piece of glass and fill with electrolyte.

I have made hundreds of those, you can do it at home it a toaster oven, google for "graetzel cell video".

This type of cell has several very serious issues:

1) The efficiency is very low

2) The cell uses a liquid organic electrolyte. Of course there are tons of problems with leakage, toxic solvents etc.
The electrolyte often breaks down from the light, you'll always have oxygen diffusion into the system and react with all the chemicals. It is extremely difficult to make anything organic that can withstand light. Have a look at your painted garden chairs after a few years in the sun.

3) The dye breaks down quickly. Make a simple test. Take a few grass clippings and put them into the sun. You'll notice that they change color from green to brown.
The reason is that the chlorophyll degrades very rapidly in the sun. Grass makes new chlorophyll all of the time.
4) Titanium dioxide (and zinc oxide as well) are highly reactive materials under illumination. This is why you use them as white pigments. The sunlight creates free electrons, and those decompose a lot of the dirt in contact with the stuff. A white wall in the suns cleans itself to a large part.
Of course, you'll have the same effect in the solar cell, the TiO2 will act as a catalyst and degrade dye and electrolyte.

Make a simple test at home: Take a wall painted with titanium or zinc white. Dissolve some grass clippings in alcohol and spray the green stuff on the wall. Expose to sunlight and see how quickly it bleaches.

As a scientist myself, I find it very sad and unprofessional, how MIT is lying to the public.
A statement like
"If all goes well, in a few years it should be possible to gather up a pile of grass clippings, mix it with a blend of cheap chemicals, paint it on your roof and begin producing electricity. Talk about redefining green power plants!"
is very misleading, unethical and close to being a scientific fraud. Of course, you could never paint it on, how are you going to put on the electrodes?

Re:Fraud - be careful (0)

Anonymous Coward | more than 2 years ago | (#38946295)

great comment, I think- I'm not a chem expert. But just to be fair, the statement about gathering up grass clippings is probably coming from "gizmag.com" rather than that lab at MIT. I used to research at MIT and magazines constantly hyped our results. I used to think it was a huge honor to be quoted in a magazine, until I realized that magazine writers are constantly on the search for interesting stories and if a story is not interesting enough, they will jazz it up by various amounts, just to be provocative, grab peoples' attention, and appear to have the newest, most extreme information, etc. I remember one reporter from the NYT in particular trying to put words in my mouth. It's essentially part of the government-press-science symbiosis (and mixing military or other security issues in there only makes it juicier). So I'm super-glad to see all of the would-be detractors grounding the hype with calculations and predictions.

That important set of experiences aside, I think it's very hard to predict just how far a technique can combine with other technologies through transectorial innovation. The Wright brothers examples are good. Who knows what obstacles and advantages this chlorophyll technique may experience in the future? Look at nuclear energy... it's potentially wayyy more efficient than everything out there, but running the reactors requires so much maintenance and safety, the poor plutonium reactors never make a profit... Maybe it would be better with thorium? The important thing here is that they have made a slight opening into the possibility and it's working enough that it makes sense to keep exploring it and pushing the technique until a clearer view is had :)

And all that because... (1)

JoosepN (1847126) | more than 2 years ago | (#38944421)

...he is too lazy to mow the lawn himself. Once it gets profitable, the golddiggers will do it for him - free of charge.

Photo-oxidative damage protection? (1)

robertchin (66419) | more than 2 years ago | (#38945365)

Without a continuously active protection mechanism excess energy will destroy the light harvesting molecules due to photo-oxidative damage. So you might have to continually repaint your roof which could get quite expensive and be labor intensive.

MIT imagines DIY solar cells made from grass clipp (0)

Anonymous Coward | more than 2 years ago | (#38945575)

MIT imagines DIY solar cells made from grass clippings

Fixed.

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