Thursday, January 16, 2014

Green Energy (Part 2): Just Leaf the Fuel Cells to the Flora

Yesterday at To Infinity And…In Theory we talked about Fuel Cells and their background story starting with the first man to dream them up (William Grove) and concluding with the man who sent them into space (Francis Bacon). If you missed yesterday’s entry don’t fret, you can catch up here. [Green Energy (Part 1): Four Score AndTwenty Years Ago Fuel Cells Were Born! …(ish)] Today we’re going to see how these pioneers who laid the very important groundwork for Hydrogen Fuel Cell technology are pushing the energy crisis out of the way.
After NASA witnessed the hidden potential of these tiny molecular powered batteries firsthand they were ecstatic to say the least. They jumped onboard the Green Tech train and launched some 200 projects using Fuel Cell research as the backbone. Sometimes it only takes one huge influence to boost innovation to invention. Since the 1960’s, laboratories all over the world have delved into these powerful technological marvels of science.
We’re going to talk just a little bit more about their history today (not much, we covered the history pretty well I think yesterday) starting from the bulky models used on Apollo to the silicon sheets half a nanometer thick today. We’ll also talk about how they work, how they charge them up, and a new harvesting technique that could make Fuel Cells the most cost effective energy option on the market to date.
Think you know Green Technology in and out? Well then, let’s put that knowledge to the test shall we.


It’s Not Easy Being Green


When Grove conceptualized the Fuel Cell in the late 1800s I doubt he had space travel in mind. Heck, at that point they barely had a grasp on it. But Francis Bacon’s Hydrox Fuel Cell blew everyone away in the middle of the 20th century. Yet the technology didn’t catch on, Ford still had a monopoly on propulsion, no one was interested in a product that had not been tested. After all, who in their right mind would want to be a guinea pig?
But NASA saw the promise. (Oh NASA, how I love you. For real.) It launched 200 projects into Fuel Cell technology and sure enough in the late 60s, Bacon’s Fuel Cells, with some slight modifications, made their journey into space a reality. They were also used again in a little project you might have heard of. Apollo, perhaps? Ring any bells? I really hope so because the Apollo program accomplished one of the greatest feats of all time.
Apollo 11 put a man on the moon.
Yep, Apollo 11 was far more important than just the prequel to Apollo 13, (no Tom Hanks here, sorry folks!) it was the mission where Neil Armstrong planted the American flag on the lunar surface. (We really have to stop claiming things that technically don’t belong to us…) But how did this happen? Well there were millions of parts in motion, but an important aspect of the mission was a Fuel Cell.
More importantly, not only was the Fuel Cell capable of splitting Hydrogen and Oxygen in order to produce energy, it could reassemble the molecules to turn them back into water. I’m sure it was filtered, but this is what the Astronauts drank. Hydro Fuel Cell H2O.
So how does it do this? It’s pretty cool actually; I’ll break it down for you.
The Bacon Cell is essentially an Alkaline Fuel Cell, and boy are they efficient. What’s happening is called a Redox reaction. (Red = Reduction, Ox = Oxidation). This can be as simple as oxidation of carbon to yield Carbon Dioxide, or as complex as producing glucose inside the human body, both are forms of a Redox reaction.
Well this concept is happening inside the battery. (A stack of fuel cells). At the anode hydrogen is being oxidized. When this happens it enters its liquid state, water. It then re-enters the module and returns to the cathode where the water is then turned back to hydroxide ions. The cycle keeps repeating itself, thus creating a regenerative supply of energy. The best part of all you ask?
Electricity and heat are the byproducts. That means powering the ship, according to a molecule, is just their waste.
The electrodes are separated by an aqueous alkaline solution. It’s the catalyst for the reaction to produce water and electricity. There’s only one slight problem. If Carbon Dioxide gets into the Fuel Cell it can “poison” the entire system, compromising everyone onboard the ship. (Seen the new Sandra Bullock flick? Being compromised in space is scary stuff!) Because of this both pure oxygen is used and a scrubber is incorporated into the system so as to filter it after each pass. So why don’t we use this for the general public?
The poisoning effect we just talked about is one of the reasons. It can happen fairly easy, and if it does, it’s pretty much irreversible. Considering we expel carbon dioxide as waste from our lungs, we could potentially destroy the vehicle ourselves by just driving it. Ford would love it, but we’d be in the poor house. Pretty much, technology just wasn’t there yet for small, affordable, consumer models, after all, it was only the late 60’s, we didn’t even have Internet yet! (Or Google. What did we do before Google? I think it was like a library or like, something about Dewey…oh well.)
However that reality may not be so far away. In 1999 a transport boat that ran on AFC’s was put into commission. It was called the HYDRA. (Run Captain America!) Before they took it out of the water and decommissioned him he transported some 2,000 passengers and even won a few energy related competitions.
But now Fuel Cells, once again, have come out of the world of obscurity and are back in the spotlight. Yet now they aren’t just being looked at as a replacement technology because we might run out of gas. Now we need them because soon, we might kill the Earth if we keep it up, and running out of a planet is far more treacherous of a prospect then no more driving. At least to me, I don’t know how you feel about it.
So what are we doing to stop this bleak future from occurring? Researchers in Tennessee came up with a clever answer to that question. Let’s see what Popeye has to say about Science.

Eat Your Spinach, Sailor…


If you’re old enough to remember the man pictured above, then your childhood was most likely AWESOME! If not, I’m sorry…anyway. Do you know how Spinach makes the food it consumes? A little process called photosynthesis. Did you also know this produces chemical energy? Huh? Did ya!?
Well this chemical energy can be converted into another kind of energy, something of a kinetic variety. Mechanical energy to be exact, and at Oak Ridge National Laboratory in Tennessee, that’s exactly what scientists are looking to exploit.


It takes light 8 minutes to reach the leaves of the Spinach. In five trillionths of a second the plant is already converting that sunlight into energy. Where Alkaline Fuel Cells were efficient and their obvious replacement Silicon Fuel Cells was more so, the environment’s natural processes have billions of years ahead of us. While we’ve been trying to manufacture artificial versions of Mother Nature, Mother Nature has already created the perfect practice.
So how are they achieving this goal? Turns out you can infuse the leaves of spinach with platinum. Because chloroplast is already a conductor for the plant to make energy with, this platinum just enhances its natural abilities and suits it toward technology we can use. The best part of it all, it’s 100% green.
The platinum turns the spinach leaf into an electrical switch. Biometric scientists are looking toward this technology for use in the blind. It has the potential to be very effective for biotic eyes. Speed-of-light computers are also a potential for the same reason. The human retina registers light faster than anything we can currently build, but by using these platinum chloroplasts, it could provide the building block to make something that not only matches the speed at which the eye operates, but surpasses it as well.
Time will tell but I’m looking forward to this technology in the future. Want to know more about Spinach powered super computers? You can by clicking here.
So by now you’re probably asking yourself, “yeah that’s cool and all, but I thought this was about Fuel Cells.” Well…not that part in particular. But I just wanted you to understand the potential for plant based biotechnology, before I blew your mind. While they had one bionic eye on supercomputers when they were working with University of South Carolina to extract Spinach proteins, they had their other one trained on the future of sustainable energy.

Standing Fern on Green Energy



That complex tangle of green, yellow, and blue is actually fairly important to all of this. It’s called the Light Harvesting Complex, or LHC-II for short. It’s the protein that they pulled from the spinach responsible for the function of photosynthesis. The guys over at Clean Technica break it down the best:

Oak Ridge writer Bill Cabage describes the latest breakthrough as a biohybrid photoconversion system. The researchers were able to confirm that a particular light-harvesting protein derived from plain old supermarket spinach can be induced to assemble itself into a membrane, by putting it into a liquid solution containing synthetic polymers. The protein, called LHC-II (LHC stands for Light Harvesting Complex) interacts with the polymers to form a membrane, which in turn produces hydrogen. In other words the membrane acts as a kind of photovoltaic cell, but instead of generating electricity it generates-hydrogen.
Read more at 
Clean Technica

In short, clean, renewable, affordable, sustainable, and literally green as you can get energy. There is a catch though. This technology doesn’t come cheap. Platinum is incredibly expensive. But researchers at MIT may have an idea that could reduce that cost significantly.


“Leafing” It All Behind…



As I mentioned before, Platinum is super expensive stuff. Not to mention, it’s fairly uncommon as far as rare Earth elements go. Another problem with Fuel Cells was the ability to keep them self-contained and contaminate free. But that could theoretically be a thing of the past thanks the brilliant mind of Daniel Nocera. Toiling hard night and day in the bowels of MIT, he finally seemed to figure it all out.
He would grow trees that produced hydrogen instead of oxygen.
HA! Nope, but I had you going for a second there didn’t I? It might as well be that though considering the principle they operate on is exactly the same as a leaf.


No not the leaf, the thing on the leaf. And no, you don’t have to attach them to a leaf, they are self-contained and operational. No planting required. But the million dollar question is how do they work? It’s not a mystery, it’s just science.
When sunlight hits a leaf it begins to cause a chain reaction. The sunlight begins to convert chemicals within the leaf into free oxygen by breaking down water. That oxygen is then released back into the environment for us to breathe. This is basically how photosynthesis works though there are much more complex things happening, (HowStuffWorks.com will tell you all about it here.) But we should quickly clarify what we mean by “leaf”.
The artificial leaf may be a bit misleading; it’s actually called a Photoelectrocell. Photoelectrocells differ from Photovoltaic cells significantly. Voltaic cells generate voltage when light hits them, while Photoelectric cells generate electricity from light. Voltage determines the electric potential, meaning how much power there is going to be. (i.e 9V batter, 12V battery etc.) A Photoelectric cell converts it into electricity, like a solar panel, and its power is determinative of its capacity and how much energy is available. But anyhow, back to fake leaves.
By using the same basic principles of photosynthesis with only a few slight adjustments, Nocera created the little wafer pictured above to basically do just that. Except instead of producing free oxygen for us to breathe, it breaks down water into oxygen and hydrogen for us to use to power our cell phones, cars, laptops, and robotics. By placing it in a tankard of water (refilled daily) the Photoelectrocell can make all sorts of things happen.
And it’s fairly cheap.
Instead of running mostly on Platinum it uses very little of the precious element. It’s mainly comprised of Cobalt, Zinc, and other fairly inexpensive metals and minerals. The wafer is then coated in a sheet of silicon that is thick enough to better protect the metals from oxidation (rusting is a form of oxidation. Oxidation is what destroys the electrodes.) Yet thin enough to allow the reaction to take place effectively.
But in order for everything to work proper, clean water is the essential ingredient. Testing is currently underway to make one that can survive in slightly more contaminated environments but after a while it still clogs the chip and the process stops working. They also discovered another unique property of this, to a degree the silicon area of the chip will repair itself. Nocera and his team noticed this when they roughed up the surface in an attempt to discourage grime and biofilm from building up on the artificial leaf.
Unfortunately keeping contaminants out continues to be a problem. While a closed cell is possible, water is still needed for the initial catalyst. Clean water at that to avoid degrading the material faster than necessary. Not all parts of the world that could certainly benefit from this technology have ready access to clean water. Plus, in order to keep it cost effective, an open cell where water can continually be refilled is preferable as it wouldn’t have many special requirements that quickly add up to total wallet devastation over time. 

A Green Future (Literally)

As the price of solar technology continues to drop and the mass production of artificial leaves becomes a priority, Dr. Nocera claims we may see this technology in every household worldwide in as little as five years. But if there is one thing I know about the world it’s that the people with money don’t like to let go of it, and major power companies are not going to like this tech one bit.
Because of its potential to be extremely cheap to produce, it would be reasonably priced for the Consumer. If two panels cost $60, and two full size panels (we’re speculating here only) could potentially run a two story house, then pretty much anyone in the world could afford them, even in the most impoverished areas. Let’s face it; it would put Consumer’s Energy out of business and all other power countries worldwide.
Right now it’s estimated that the current cells cost around $6.50 USD to produce. While fossil fuels are sitting pretty at the height of popularity still, Fuel Cells are back. And just like when Grove powered the telegraph and truly became the definition of Avante Garde, they’re in line to change the way we live in this ever developing world.

-       Ryan Sanders


Thanks for reading! And as always if you want to know more about solar powered spinach, wireless Fuel Cells, or the artificial leaf and its creator follow any of the links below. Share it around, after all, everyone loves science!  Happy learning!



*Correction: In yesterday’s article I said the technology to turn Spinach into electrical switches was patented in the 1990’s. That was a typo. I meant 1980’s; the actual patent was issued in 1985. Sorry about that folks but mistakes do happen. - Ryan Sanders



No comments:

Post a Comment