By Christopher Moore
Edmund Scientific recently asked me to review some products for them, so the first item I picked was one I’ve had my eye on for years: a hydrogen fuel cell model car. Recently I wrote an article about advances in fuel cell catalyst technology, so fuel cells are an interest of mine that may one day find a way into my research.
The model car Edmunds sent me is manufactured by Heliocentris. It is the Hydrogen Fuel Cell Model Car Demo kit and comes with a solar module, a reversible proton exchange membrane (PEM) fuel cell (operates as both an electrolyzer and a fuel cell), and a car chassis with electric motor. Its operation is simple: you fill the fuel-cell with water, plug it into the solar panel, and the electricity generated by the panel electrolyzes the water, forming hydrogen and oxygen gas. Once you’ve made enough gas, you plug the fuel-cell into the car. The hydrogen and oxygen recombine producing a current that powers the electric motor making the car move.
I’ve had a lot of fun with this item, and I have lots of plans for it. Specifically, I’m using it as a demo during an upcoming talk on fuel-cell catalysts, I’m working with a student at a local high school on a Virginia Junior Academy of Science project involving PEM fuel cells, and I’m developing a presentation on basic fuel cell technology and energy for a group of fifth graders at an area elementary school. Needless to say, I find this toy useful and incredibly fun. It runs on water! Sort of. (You do need a little solar energy to make hydrogen gas, and technically the car runs on hydrogen. But whatever.)
A short video demonstrating the operation of the car is provided after the jump along with a more detailed review and purchasing information.
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By Christopher Moore
Fuel cell devices directly convert chemical energy into electricity by electrochemical reactions, and have received recent interest due to their lack of moving parts and relatively clean operation. Various types of fuel cells are currently discussed in the scientific literature, though polymer electrolyte fuel cells (PEFC) show characteristics that would make them suitable for automobile engines that produce zero emissions. (For a discussion on fuel cells in general, see this article.)
Several problems currently exist that limit the commercial viability of PEFCs, the largest being the cost of catalyst material. Though Pt has historically been the optimum cathode electrocatalyst for fuel cells, [1] the use of expensive Pt and Pt-based catalysts in fuel-cell electrodes makes their cost prohibitive. Since Pt requirements scale with fuel-cell size, large-scale fuel-cell costs can not be reduced through efficient production and economies of scale. If the transition to a hydrogen economy is to be realized, reductions in fuel cell costs are necessary. Otherwise the familiar rallying cry “no blood for oil” may be replaced by “no blood for platinum”. Recent studies have been conducted on means to reduce the amount of platinum necessary for successful catalysis, as well as studies to eliminate platinum from the process altogether. Specifically, in this article I examine studies of platinum monolayers, palladium alloys, and cobolt-polypyrrole composite catalysts.
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By Christopher Moore
Gas prices have soared bolstering arguments for alternative energy sources. But are these alternatives any better? Any cheaper? Let’s see.
The recent price spike in the U.S. is not due to a global shortage of oil. Hurricane Katrina disrupted several major oil refineries and has hindered distribution to the 48 states, causing a very local shortage. Experts expect the price to settle back to pre-hurricane levels within a few months. Of course, this doesn’t address the larger issue: are we running out?
Most geologists consider fossil fuels to be “non-renewable,” meaning that one day we will run out. There is a small minority though that are not convinced this is the case. Some evidence is given in this article as well as this one by George Crispin.
There are a couple of theories about how fossil fuels are created. The most popular is that oil is biogenic and comes from plant and animal matter such as bone (hence “fossil” fuels). Of course, we add new bone to the Earth daily, meaning we should be adding to the oil supply daily, correct? Not exactly. What geologists mean by “non-renewable” is that we can’t make any new oil within a human time frame. It will take millions of years for my bones to turn into usable oil, and we are using oil faster than Mother Nature can create more.
The second theory of oil creation is that it is abiogenic, meaning all of the oil we have was formed with the Earth over 4.5 billion years ago. Dr. Thomas Gold has proposed a model based on this assumption that shows oil potential far greater than what many believe is currently available.
Right now, I will have to side with the conventional biogenic theory because I am no geologist. I trust the cadre of competent scientists who are pretty sure they are right. I’m no pessimist, though. I believe we have a while until oil production cannot keep up with demand. But if we are to run out, what are the alternatives?
The U.S. Government is gearing up to spend $1.7 billion to make hydrogen fuel cell cars a reality. Read this article to learn how they work.
Here’s the problem, though. Although hydrogen is the most abundant element in the universe, it is not cheap to come by in its elemental our gaseous state. If you pull the oxygen off of H2O, then you have hydrogen. But it takes energy to do this. It takes more energy to create hydrogen gas than we can get out of its use. Oil we just pluck from the ground and light. That’s it.
Also, the reaction that powers a hydrogen fuel cell requires platinum as a catalyst. Platinum is expensive because it is VERY RARE. So in a hydrogen economy, you may see long-haired protesters waiving signs reading “No Blood for Platinum.”
So we are faced with many problems. Other alternatives have similar problems. The solutions are not obvious. We use oil because oil is cheap, plain and simple. When it fails to be cheap we’ll find something else to move our economy. Or we’ll find something cheaper. Either way I have faith in human ingenuity to solve what may be a problem sometime in the future.
Here’s a quote from the former oil minister to Saudi Arabia, Sheik Yamani: “The stone age ended, but not because of any lack of stones. Undoubtedly the oil age will end the same way.”
