What better way to get kids and teens interested in alternative energy and physics than with a
Hydrogen Fuel Cell Car science kit? Not only will your future scientist have fun building learning how we can derive energy from
hydrogen, but they get a hands-on working
hydrogen car building project. Will they end up becoming one of the future scientists who help to make
hydrogen a viable energy source? Using a device called a PEM
hydrogen fuel cell, such as the ones sold by Science Store for the Stars, the chemical energy of
hydrogen can be converted into electrical energy we can use.
PEM means Proton Exchange Membrane and is similar to a battery, which also converts chemical energy into electrical energy. However, a battery has a fixed amount of chemicals inside it and a
hydrogen fuel cell can continuously have
hydrogen and oxygen added to it meaning no recharging or throwing it away! The PEM dates back to 1839 when English physicist William Robert Grove first demonstrated his “gas voltaic battery.” His experiments paved the way for the PEM fuel cell first developed in the 1960s by General Electric which provided electric power and drinking water onboard the Gemini spacecraft.
Hydrogen fuel is a wide open field of science as many alternatives to the current gasoline model of vehicles are being studied and experimented with.
We consume conventional petroleum based fuels 100,000 times faster than they are being made available, raising many questions about how long our conventional energy supplies will last. China, and possibly India, will soon surpass the United States in energy needs meaning viable energy alternatives will become even more important. Could
hydrogen power be the future? But before you get too excited, there are still many hurdles to leap before
hydrogen cars become main-stream.
Many of the top scientists and engineers all around the world are in a race to overcome a number of commercialization and technical issues with
hydrogen fuel cells and most automakers including Toyota, Ford, Honda, and GM are all researching the potential of this incredible source of energy. The fuel cell in a
Hydrogen Fuel Cell Car kit is the same process used by passenger
hydrogen cars that will be available for us to purchase in the near future. With a
hydrogen/electric hybrid car, such as the Toyota Highlander SUV, you’d head for the nearest
hydrogen filling station and fill the tank with
hydrogen gas (H2) at about 10,000 pounds per square inch. As you drive around, the electric batteries are charged by the
hydrogen/oxygen chemical process and regenerative breaking (current gas/electric hybrids also employ this) to charge the batteries. The car itself actually runs on an electric engine. As a matter of fact, there are currently
hydrogen busses on the road in some major cities.
So how does a
hydrogen fuel cell work? The Fuel Cell Car kits contain a reversible PEM fuel cell which means Proton Exchange Membrane. Being reversible, the fuel cell can operate both as an electrolyser, producing
Hydrogen (H2) and Oxygen (O2) from water (H2O), and also as a fuel cell (reverse electrolyser) to convert the chemical energy of
Hydrogen to electricity with the by-product being water vapor and heat.
Let’s first look at the process of turning the
hydrogen (chemical energy) into electricity to power our car. This is the reverse electrolysis or fuel cell. The PEM fuel cell consists primarily of four components, the anode (negative electrode), the cathode (positive electrode), a catalyst and an electrolyte.
Hydrogen gas pumped into the anode strikes the catalyst (a thin layer of platinum) and splits into
hydrogen protons and electrons. On the opposite side of the fuel cell, oxygen enters the cathode. Sandwiched between the anode and cathode is a thin electrolyte membrane that looks like plastic wrap you’d find in your kitchen. It permits the positively charged protons to pass through from the anode to the cathode but blocks the negatively charged electrons which are forced to flow through an external circuit to form an electric current.
When the electric current returns from doing work, such as powering an electric motor, it reacts with oxygen and the
hydrogen ions at the cathode to form water and heat. That means no smog-forming emissions or greenhouse gasses! Now let’s look at the electrolyser - the process of breaking water (H2O) into
hydrogen (H2) and oxygen (O2). When a chemical charge is applied to water, the charge breaks the chemical bond between
hydrogen and oxygen and creates charged particles called ions. In this case, positively charged
hydrogen ions and negatively charged ions are formed.
An electrolyte, also called an electrolytic conductor, is a conducting medium in which the flow of current is accompanied by the movement of matter in the form of ions. An electrolyser has 2 electrodes where the ions form. One electrode, called the anode, is positively charged, and attracts the negatively charged oxygen ions. The other electrode is called the cathode and attracts the positively charged
hydrogen ions. But to break the bonds of water requires energy.
What makes
Hydrogen fuel so attractive? As mentioned before, the only by-product is water, so there is no carbon or other emissions to harm the environment. It is non-toxic, clean to use, and holds much more energy per unit of weight than any other element we know. It is also the least complex and most abundant element of our visible universe so we know we won’t run out any time soon! And
Hydrogen may one day power not only our homes, but even small electronic devices. The limits are only in our minds.
What are the downsides? The major downside to
hydrogen powered vehicles is the energy needed to create the
hydrogen. Although a car than runs purely on
hydrogen is not emitting any pollution, the
hydrogen you just bought to fill your tank had to be created using electricity in some form. If a coal, oil, or gas plant created the energy, then carbon monoxide was created to make the
hydrogen. All of a sudden your “green” car isn’t so clean, is it? If you’re using a
hydrogen/gasoline hybrid, you’d use less gas, but you’d still be using gas. Also, PEM fuel cells don’t create much energy. To get enough energy to power a car, for example, engineers must stack hundreds of fuel cells together in a series. This means a more complicated system with more ways for something to break down.
And how much are you willing to pay for a
hydrogen car? Because the technology is so new and
hydrogen cars are not being mass produced, the price alone will be too much for the average American to afford, at least in the near future. Availability of filling stations is another issue. It will be very costly to install
hydrogen filling stations to the same degree as we currently have gasoline stations. Currently, the easiest places to find a
hydrogen filling station is in Orange County, California, Westchester County, New York, or Washington, D.C. Travel more than a hundred or so miles outside these areas and you may get stranded. These are just some of the issues that are waiting to be solved by a future scientist.
What advancements are to there to be made? Plenty! Auto companies are looking into creating
hydrogen without using carbon emitting sources like coal plants. Solar power is one consideration being investigated. However, solar panels are currently not very efficient (another great scientific field of study) but would be a clean renewable source of energy to produce the
hydrogen if it can be done cheaply and efficiently. There is much advancement to be made in the fuel cell design itself. Honda solved one problem simply by re-orientating the position of the fuel cell. Traditionally, fuel cells were placed lying flat under the floor of the car which meant the water created as a by-product needed to be aggressively pumped out of the fuel cell using more energy.
Honda’s FCX hydrogen car has a vertically oriented fuel cell, allowing gravity to do much of the work and saving energy. Wasn’t that a great idea? The size and efficiency of the
hydrogen engines is another area where future improvements will be important as well as better ways to cool the engine. As you can see there are a many opportunities in the science field of
hydrogen fuel cell development, and it’s a very interesting subject.
Although some of this may sound complicated, it becomes much easier to understand when you’re building, hands-on, the actual
Fuel Cell Car model.
Hydrogen Fuel Cell Car kits are popular for kids starting at about age 10 and up and are great science fair projects. Even many adults find them fascinating and they’re a fantastic way to participate in a project with your child. And whether they become the next great scientist or not, it’s just a fun way to learn science!
Credits :
Tom Ryan
