 Not surprisingly, the element which powers the sun, hydrogen, is also the perfect source of energy here on Earth! Hydrogen is the simplest element known to man. A hydrogen atom consists of one proton and one orbiting electron. It's actually the simplicity which makes it such an ideal energy source. Unlike hydrocarbon fuels, hydrogen is completely non-toxic to humans. Also unlike hydrocarbon fuels, hydrogen is the only fuel that is completely renewable. Hydrogen produced using solar electricity (by running a water electrolysis unit) and then burned or used in a fuel cell turns back into water (see diagram at left). No pollution is released in making it, no pollution is released when using it! This cycle can be used indefinitely as well. It is also the lightest element known to man. This gives it a rapid dispersion rate when released into the air, so rapid than in order to ignite hydrogen you would have to get right up next to a source, much unlike gasoline or even natural gas which tends to pool and remain in dangerous concentrations for long periods of time. Hydrogen is certainly flammable, which makes it a wonderful fuel, but unlike all other fuels it creates no pollution when combusted in air. The only thing left over from burning hydrogen is water vapor, pure enough to drink! One of the great misconceptions about the dangers of hydrogen stem from the Hindenburg airship disaster. Almost anyone you ask will tell you that hydrogen was to blame. In reality, post accident studies revealed the true culprit was the aluminum-oxide based paint with which the entire skin of the blimp was painted. The paint contained a chemical composition similar to solid rocket booster fuel. As the air ship traveled through the air it accumulated a sizeable static electric charge on the ship's skin. When the ground crew caught hold of the guide ropes it caused the ship to become electrically grounded, which then caused a large spark on the skin of the craft. This spark ignited the paint and caused the craft to burn rapidly. Of the 43 people that died in the incident, 40 died because they jumped off the craft and 3 died from diesel fuel burns (the diesel fuel continued to burn on the ground for 15 hours after the accident!). When the hydrogen burned, its flame went straight up into the air, away from the people, and was completely consumed in less than 3 minutes! Upon further study it was found that of all dirigibles, the ones using hydrogen as a lifting gas had a better safety record than the ones using helium.
Does that mean hydrogen is completely safe?... NO, BUT IT'S SAFER THAN GASOLINE! Make no mistake, hydrogen is an explosive fuel! As with all combustible fuels, great care should be taken in its handling. Hydrogen has a wide flammable temperature range and is therefore rather susceptible to ignition from static discharge and other sources of low heat. Hydrogen also continues to be flammable in a wide concentration range in air (4 to 80% of hydrogen). This is counterracted though by its rapid dispersion rate and its ability to permeate typical wall structures. In fact, even air-tight rooms will not contain hydrogen! This is why a hydrogen leak in an enclosed room, in a typical home, still gives very little chance of ignition -- and remember that hydrogen is non-toxic. The bottom line is that there are specific conditions in which hydrogen will ignite and be potentially dangerous. However, if one is aware of these conditions, it becomes easy to avoid them. We offer a quote from Hygen Industries:
"Dr. Fred Edeskuty, the former Chief of Hydrogen Programs at Los Alamos in New Mexico, once gave this analogy; If you were driving down a two lane highway with no shoulder, just a steep 1000 ft. mountain on both sides, and coming towards you in the opposite direction were two tanker trucks - one in each lane, one hydrogen and one gasoline, and you had nowhere else to go, you are about to hit one of the trucks, there is no avoiding a crash. He said your best chance of survival would be to aim for the hydrogen truck. We rest our case."
How is hydrogen used as a fuel?... Hydrogen is incredibly flexible as a fuel. It is very combustible and can therefore be used to run internal combustion engines (ICE's). It is also the primary fuel being considered for running fuel cells. Burning hydrogen is just like burning any fuel. It's a process of oxidizing, or combining with oxygen, the molecules of the fuel while creating heat at the same time. In hydrogen's case, putting it with oxygen simply creates H2O! Actually, the part of gasoline that "burns" IS the hydrogen. Combusting one gallon of gasoline creates one gallon of water too. The problem is the carbon and sulphur that are also released into the air and into our lungs. Hydrogen itself has a higher heating value than gasoline and contains 3 times more energy per pound than gasoline (refer to the Hydrogen Combustion page for a more detailed explanation). These qualities make hydrogen an ideal fuel for combustion in, say, a backup generator for instance. An ICE can easily be converted to run on gaseous hydrogen. The difficulties come in how to store the hydrogen since it is also the most voluminous fuel. Refer to the table at the bottom of this page for a brief overview of the new advances in hydrogen storage and generation. In the case of off-grid living, solar panels normally put their excess energy into storage batteries during daylight hours. At times of extended cloud cover, backup ICE generators are used to supplement the drained battery pack. These generators often use gasoline, diesel, or propane as their fuel thereby suddenly turning an eco-friendly setup into a violent offender. As an alternative, such a system could be configured to produce hydrogen via electrolysis using the excess electricity. This hydrogen could then be stored in tanks, much like propane, and in times of extended cloudcover could then be used to power a backup generator. This hydrogen could also be used for cooking and heating, a task normally reserved for propane or natural gas. This could turn a home into a completely energy self-sufficient operation. Such systems have been built and tested but are still as yet commercially unavailable, although not out of reach for those willing to "do it themselves" and "get their hands dirty". Visit the American Hydrogen Association's website and take one of their courses that teach you how to do hydrogen ICE conversions. Homepower magazine has many free-to-download articles on how to electrolyze water using solar power to get hydrogen. Those who live off-grid today still have to buy non-renewable petroleum-based polluting propane or natural gas and are therefore still not completely independent and self-sustaining. Hydrogen is the missing piece of the puzzle that can truly and completely enable self-sufficiency for those tired of being dependent on the oil and gas monopolies.
What about fuel cells to power my home?... The other, and perhaps better, method of using hydrogen as a fuel is to power fuel cells. A fuel cell is an electrochemical device that converts hydrogen and oxygen gases directly into electricity, with the only by-product being pure water and heat. Eventhough fuel cells have received huge attention from the automobile sector, the more immediate use for them is in the distributed generation market.  Distributed generation is where each individual home or business generates its own electricity. This has already been done for many years using solar power and stand-alone diesel or gasoline generators, but fuel cells offer perhaps a cheaper and definitely more efficient alternative. You see, solar panels are only about 12% to 15% efficient and, compared to other forms of generating electricity, quite expensive. Aside from being relatively inexpensive, ICE generators are noisy, dirty, polluting, powered by non-renewable fuels, as well as being only 25% to 30% efficient. Fuel cells, on the other hand, are quiet, clean, use a renewable fuel (hydrogen), are non-polluting**, and are between 40% to 50% efficient (slightly less under heavy loads). Initial price estimates for 2 - 3kW home generation units are between $8000 and $10,000. Considering the cost of an equivalent solar power system is about $20,000, this new addition to off-grid and on-grid distributed generation alternatives is certainly welcome. Another advantage to fuel cell sytems is called "co-generation". Co-generation is where a device is used to generate electricity and heat for the home simultaneously. Fuel cells are perfectly suited for this dual role. Although not currently available to the average consumer, initial production runs have already begun and pilot testing programs are already in progress all over the country. Initial inventories are expected to be sold exclusively in the California market, with the rest of the country to follow soon after. Also to be released very soon are small fuel cell backup generators from Coleman, a leader in camping equipment. The major players in this market are PlugPower, HPower, Greenvolt, Hydrogenics, with many others popping up fast.
(**Fuel cells that use hydrogen as the fuel create no pollution in and of themselves. However, since hydrogen is not widely available, manufacturers have turned to natural gas as the feedstock. Under this scenario, natural gas is fed into a reformer which strips the hydrogen from the carbon using heat. The carbon then combines with oxygen to form carbon monoxide, a deadly gas. The next step uses steam to transform the carbon monoxide into carbon dioxide which is then released into the atmosphere. Although still less polluting than gasoline powered ICE's, CO2 is still a pollutant that contributes to global warming. Tests have already shown that the pipelines used to deliver natural gas to our homes could be used to deliver hydrogen without any modifications. Until that happens however, a homeowner can still choose to make his own hydrogen using solar or wind and use it to run the fuel cell generator to power his home at night, as well as provide for cooking and heating.)
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