We recently wrote about how hydrogen production is a costly endeavor
for our water supply, as well as the electric gird, effectively making traditional methods of manufacturing a near-impossibility. But Bruce E. Logan, professor of enivronmental engineering at Penn State, has developed a technique that could change that.
Logan suggests using microbial fuel cells that run on cellulose to produce the hydrogen from natural processes rather than converting it to ethanol. By using bacteria in a microbial cell with acetic acid (vinegar), electricity, about 0.3 volts worth, was produced. The bacteria consumed the acid, releasing electrons and protons, which were captured by a cathode and anode rig, which allowed for current. When they added 0.2 volts into the mix, hydrogen gas was produced. Admittedly the amounts produced were very small, but the efficiencies here are large and they are quick to point out that "this process produces 288 percent more energy in hydrogen than the electrical energy that is added to the process."
On top of that, they are seeing between 23-56% efficiency at extracting hydrogen from sugar-based crops, which, being that the technology is new, is impressive given that conventional hydrogen production methods are only at 70% efficiency, with little likelihood of increasing further. Logan is also developing systems
to harness bacteria-produced electricity directly from animal wastewater and further using the byproducts to generate even more energy.
Given that the typical hydrogen economy has, until now, been based on massive consumption of (likely) dirty electricity, this new work may actually make hydrogen part of a larger sustainable future.
Image credit Zina Deretsky of the NSF.
Story Via Physorg
The Proceedings of the National Academy of Sciences has published research showing a new process by which bacteria consume fermenting cellulose and produce hydrogen – lots of hydrogen.
PennStateUniversity and Ion Power Inc. have developed a process that uses bacteria in an electrically charged fuel cell called a Microbial Fuel Cell (MFC) to get high yields of hydrogen.
Prof. Bruce Logan of PSU:
This MFC process is not limited to using only carbohydrate-based biomass for hydrogen production like conventional fermentation processes. We can theoretically use our MFCs to obtain high yields of hydrogen from any biodegradable, dissolved, organic matter -- human, agricultural or industrial wastewater, for example -- and simultaneously clean the wastewater.
Basically, we use the same microbial fuel cell we developed to clean wastewater and produce electricity. However, to produce hydrogen, we keep oxygen out of the MFC and add a small amount of power into the system.
The bacteria consume acetic acid, which is produced in the cellulosic fermentation process or in the Mix Alco process. Cellulosic fermentation requires enzymes to convert cellulose to sugars that can then be fermented. The Mix Alco process converts cellulose to acetic acid through a process that mimics how a cow’s stomach digests grass.
The Department of Energy has found an algae that makes hydrogen, which means we might be at the dawn of an interspecies competition for hydrogen domination!
Via: Wired Science
Michael Webber, the Associate Director Centre for International Energy and Environmental Policy, has completed an analysis of the water requirements for a burgeoning hydrogen economy slated to arrive near 2040. Around this time, it is predicted that the annual production of hydrogen would top 60 billion kg. The hydrogen, of course, will be coming from water, and he estimates that 19-69 trillion gallons of water will be needed for electrolysis and for coolant of power plants. Considering that means somewhere between 50-200 billion gallons of water per day, water is looking more and more not to be the inexhaustable resource as it was once touted, not to mention that this needs to be fresh, distilled water... so much for the oceans without energy-intense desalination plants.
To add fuel to the fire, electrolysis is only currently at about 60-70% efficiency. At 100% efficiency, a rate we will never achieve, it takes 40kWh to produce a kilogram of hydrogen. This means between 1134-2754 billion kWh at an efficiency of 75% will be needed to produce the amounts they are predicting.
With local water resources being depleted, water prices skyrocketing and the question of where these billions of kWh will come from, Michael makes a sobering statement in his report:
Each of the energy choices we can make, in terms of fuels and technologies, has its own tradeoffs associated with it. Hydrogen, just like ethanol, wind, solar, or other alternative choices, has many merits, but also has some important impacts to keep in mind, as this paper tries to suggest. I would encourage the continuation of research into hydrogen production as part of a comprehensive basket of approaches that are considered for managing the transition into the green energy era. But, because of some of the unexpected impacts—for example on water resources—it seems premature to determine that hydrogen is the answer we should pursue at the exclusion of other options.
At EcoGeek, we think that hydrogen is exciting, and if done correctly, in a nice sustainable way, could potentially be an exciting clean fuel for the future. The problem is... trying to store the darn stuff.
Unfortunately hydrogen's teeny weeny itty bitty-ness means that although it compares favourably to many other energy-carriers by weight, volumetrically, its performance is poor. Also, this teeny-ness means that it can squeeze through the smallest of spaces over time. Which is why hydrogen storage is a real head-scratcher.
Luckily, progress is being made... Some exciting work by researchers at the Universities of Cardiff
, Manchester and Birmingham in the UK, have created an organic polymer that can store three percent hydrogen by weight. This is very exciting, as storing hydrogen is such a major challenge. The Department of Energy estimates that six percent is the sweet figure the scientists need to work towards, to make a vehicle with a range of three hundred miles; however, this improvement is a quantum leap forward from the one point seven percent previously achieved.
Work continues on the project, with the aim to make the polymer even more porous... We here at EcoGeek think that this is plastic-fantastic!
The BMW press event was possibly the fanciest I've seen. The X-5 which
I couldn't care less about, has slightly better fuel economy than it
used to, but they've made it bigger, meaning that the technological
advancements could, in fact, have made it significantly more fuel
But the real news was the unveiling of the Hydrogen 7, a liquid
hydrogen combustion vehicle that can also run on gasoline. The vehicle
has serious limitations, of course. The hydrogen tank will only take
the car 125 miles, while the gasoline tank will take it 300 miles.
Plus, the car isn't really for the mass market at all. A hundred of
them will be distributed across the country, fifty of them in the LA
The Hydrogen 7, just like all the hydrogen powered vehicles being
showcased at the LA Auto Show, is waiting for the future. The
infrastructure isn't there, the methods of producing cheap hydrogen
aren't there. We're just gonna have to wait. But, in the future, a car
that can seamlessly transition between multiple types of fuel could be
very important to the widespread adoption of alternative fuels.
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