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MIT Envisions DIY Solar Cells Made From Grass Clippings
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!"
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."
Let's call it what it is, Anti-Social Media.
Let's see what XKCD says about it...
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.
SJW: Someone who has run out of real oppression, and has to fake it.
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.
And yet another 10 years later they find that those "cheap chemicals" cause cancer...
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?
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.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
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...
An excuse to build my very own hobbit house!
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.
... or an unblocked view of the sky for that matter.
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
Having grass on the roof adds a whole new meaning to getting high.
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).
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.
They were right - the revolution did not get televised. It was posted on YouTube instead. All in 120 characters. SLOOSH!
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 ...
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.
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.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
They figure with $30-40 million in government grants they may be able to double that.
Paying taxes to buy civilization is like paying a hooker to buy love.
Not that it'll produce enough current to be dangerous.
1) reduce electrical demands 2) use more land 3) ...
So do expensive ones. Demand the best!
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.
I have a sneaking suspicion that whoever wrote the summary has never applied for a building permit before.
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?
Faster! Faster! Faster would be better!
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.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
1) reduce electrical demands
Yeah, good luck with that.
How does it feel to be a liar with pants constantly on fire?
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.
Let's stop polluting the world and let the natural photosynthesis do the job.
Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
A modified type of dye sensitized solar cell, nothing new.
https://en.wikipedia.org/wiki/Dye-sensitized_solar_cell
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?
"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?
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Just curious if one side always has to be connected to ground?
Cheers!
Actually, it's very easy if a government wants to; they just need to tax it heavily.
Dilbert RSS feed
If you have no electricity to start with, even a little is a huge improvement. This is not meant for industrialized places.
...he is too lazy to mow the lawn himself. Once it gets profitable, the golddiggers will do it for him - free of charge.
Pedantic troll is pedantic troll
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.
And where does the electricty for the LED lighting come from? 15% efficiency is inefficient to drive this perpetual motion machine.
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
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?
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
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.
Blasphemy is a human right. Blasphemophobia kills.
It's posts like this one that make me wish for a +1 Bazinga! mod.
9% is still very inefficient. I'm pretty sure that's what Khyber meant.
(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.
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.
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.
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.
MIT imagines DIY solar cells made from grass clippings
Fixed.
Bazinga!
The good news is, we're only 20 years away from fusion power.
Understanding the scope of the problem is the first step on the path to true panic.
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.
How does it feel to be a liar with pants constantly on fire?
How do you say "Nuttin' don't get done wit'out it don't get done by da union" in Swahili?
I used to fear clowns...but I'm discovering that chimps are far, far, worse.
I would just say more land. It's amazing what huge tracts of land can do.
...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.
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
"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.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
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
I'd happily pay you Tuesday for a biopsy today!
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.
Some drink at the fountain of knowledge. Others just gargle.
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.
We are very close to Star Trek miracle land, then, since the highest efficiency to date is 43.5%:
http://upload.wikimedia.org/wikipedia/commons/d/d0/PVeff(rev111103).jpg
I'm not saying they should do that, I'm saying they can.
Dilbert RSS feed
to separate the hydrogen from water. That would seem like a better use than making electricity, but I'll take either.
MIT invents 10 things a day that simply vanish in the history of lore and myth. Media should stop paying attention to MIT assosciated projects unless they're truly in the production phase or awaiting production phases.
It doesn't change the fact that your signature IS offensive, obnoxious, misogynistic, etc. But if you think it's okay, why not stick it on your work emails?
Let's call it what it is, Anti-Social Media.
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.
Nice thinking.... this is how you create jobs, and dig villages out of poverty. Now everyone who wants this solar electricity mat is forbidden from doing it themselves, so they'll have to hire a member of the union of village electricians, who will have to be trained by someone with the proper certifications, giving rise to a whole new training industry as well. Since a chemical expert is required to actually put the mat together, the electrician is only allowed to install it, and some other kind of worker is the only type of worker allowed to transport it after assembly, to the install site.
Even though the voltage and current output will be so small that you can barely power a small LED array.
Now if you really want to help solidify the village economies, you just need to get litigation in; perhaps a team of sue-happy lawyers could volunteer to go on a good-will mission expidition, to help build the ecosystem and bureaucracies required for lawyers to thrive, and spur an entire sector of their economies around that.
umad?
I'm sorry if it offends you. See, I only think of the HUMAN condition, not gender-specific nonsense. Therefore, I am immune to the power that words seem to have, free of the influence which your mind succumbs to.
You don't get very far in life holding onto such silly nonsense.
Die a couple of times like I have, maybe your brain will turn on some other section that will enable you to think outside of all of that.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
That's all nice and good, but the fact that you feel the need to make some sort of statement with such a gender-offensive signature says you are lying to yourself.
Sort of like how the most vociferous gay-bashers are the most in-the-closet gays, and the most "family-values fundie preachers" are the ones caught with their pants down and hooked on drugs, booze, and porn.
Let's call it what it is, Anti-Social Media.
Don't get too excited, I'm sure once the oil and coal lobbyists get done with it, they will have determined that O2 is a "green-house gas" and have all lawns taxed by the square inch for their "Oxygen-footprint"...
-Oz
>My face when you don't understand a homophonic joke.
Go back to Code Pink, where the rest of the easily-offended and thin-skinned female humans go.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
My face when you don't understand a homophonic joke.
Nice!
For the easily wooshed feminists : that's an n and "horti" sounds like "horse to".
Oopsie, just noticed, it actually sounds more like "lady working in the horizontal business", so maybe the feminists do have a point...
And have been for about 50 years now. Some things are dependable at least!
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Would I order the chemicals online using my dual boot Hurd/Linux desktop, or collect them myself in my flying car that I built using my 3d printer that I bought with the profit I made speculating on the bitcoin/facebucks exchange rate?
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Yeah that was my point. The point is that is a "research" graph not a "I can buy it at home depot or at least over the internet from a website" graph. The best research I've seen to this point is 47% so that would be a "realistic" goal for biological systems to reach. In fact they have to reach at least that, or people will probably install silicon systems instead to get more power and more reliable power (lower maint, etc).
Right now, literally off the shelf over the internet, "commodity grade" COTS panels run in the 10-15% range. There are some cheapies that are just under 10%, the infamous ? cheap per watt solyndra panels were 8%ers. There are pretty exotic 16% 17%, I've even heard of a 18% panel that only sailboaters will pay the premium for (because their deck space is limited, and if you Really want 400 watts instead of 300 and you've obviously got a bottomless pit of cash because you own a boat so you don't care if it costs several times as much...)
Frankly most of the difference in efficiency in COTS panels seems to come from glass, packing efficiency/tiling issues, mounting border and bracket issues, etc. You may as well simplify it to the theoretical maximum for a perfectly assembled system of infinite size with infinitely perfect glass and perfect infinitely thin mounting brackets and edge protection brackets would be somewhere just above 15% at this time. I'm sure in the future that will continue its slow rise...
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
FYI, the "lead a horiculture" quip was invented by a woman.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
A much better use for grass clippings and leaves is to gather them up and pile them in them in large mulch collector in the basement, then use that to heat the house. The average yard collects enough mulch to heat the entire house as well as assist heat the water to around 70 degrees for the entire year for an average household. Go Google "Free Hot Water from Compost Wheelie Bin" the same concept on a larger scale can also be used to heat a house. I filled trash bags a few years back with yard mulch to test it out, and it worked, 68 degrees inside the bag when it was 32 degrees outside. The end result? Free mulch for your yard to grow more leaves and grass! Now this is what I call "110% exponentially green energy!"
Irrelevant. That's like a white guy going around using the N word because blacks do it among themselves. Why don't you try it and let us know how it works out.
Let's call it what it is, Anti-Social Media.
You're right. it's very easy if a government wants to.
Rolando
Reparar
How do you make a hormone? Kick her in the stomach!
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
BTW, the Feminists don't have a point. XD
http://en.wikiquote.org/wiki/Dorothy_Parker
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
You wouldn't just tax energy usage, you'd cut something similar, like sales taxes, in exchange for the tax increase, and then explain to the public that it's really an opportunity to lower their taxes if they use energy more efficiently (i.e. find and replace inefficient appliances, and shift as much usage as possible into off-peak hours). It would still get stiff resistance from anyone in the energy supply chain, but that's pretty standard for public politics.