Steam Reforming - Only traces of hydrogen are found free in nature, so it must be separated from hydrogen compounds. There are many ways to do this, but 95% of hydrogen is produced by steam reforming. The chemical reaction, when natural gas (CH4-methane) is combined with superheated steam, is: CH4 + H2O -> 3H2 + CO (carbon monoxide). A secondary reaction called water-gas shift yields more hydrogen and carbon dioxide, a greenhouse gas: CO + H2O -> H2 + CO2.
Electrolysis - Running an electrical current through water breaks it down into hydrogen and oxygen: 2H2O -> 2H2 + O2. You can easily see this for yourself by adding a pinch of baking soda for a catalyst to a glass of tap water and dropping in a good 9-volt battery. Bubbles of hydrogen will come off the negative terminal (cathode) and fewer bubbles of oxygen will come off the positive terminal (anode). In commercial production, membranes are used to separate the two gases. Unless renewable electricity is used, the cost of splitting water and compressing the hydrogen is high. Electrolyzers can be designed to self-pressurize hydrogen to several thousand PSI. Anyone can build their own home-scale electrolyzer.
Gasification- Municipal, agricultural and forest waste biomass are burned for heat energy, but gasification is a cleaner and more efficient alternative. Solid biomass consists mostly of hydrogen, carbon and oxygen. During gasification biomass is heated in the absence of oxygen. The end product, after a series of chemical reactions, is syngas - a mixture of hydrogen and carbon monoxide (aka wood gas, town gas and producer gas). Syngas is a fuel that can be used for making steam, cooking or running vehicles and generators. Before electricity, syngas was used in the late 1800's for gas lights. Because of the high 1200 degree F temperature, smoke, tar and hazardous substances like dioxin are broken down and recombined as syngas, instead of going out the smokestack. Gasification can also produce a form of fine-pored carbon called biochar. It is an excellent soil amendment which retains water and is a paradise for beneficial soil micro-organisms.
Using Hydrogen
Fuel Cells - A fuel cell is sort of the reverse of an electrolyzer. An electrolyzer uses electricity to separate water into hydrogen and oxygen. A fuel cell combines hydrogen and oxygen back into electricity and water. There are many different types of fuel cells, but they all are used to turn H2 and O2 into electricity. Some systems include natural gas reformers to supply the hydrogen. Oxygen comes from the air. Fuel cells are still expensive because they need expensive platinum for a catalyst. The amount of platinum required has been reduced 10-fold and thousands of researchers are looking for the Holy Grail of a cheap catalyst. Prototype fuel cell cars have been on the road for 10 years and Hyundai's fuel cell Tucson hybrid goes on sale in the spring of 2014. Quiet fuel cell generate electricity on submarines during silent running. Fuel cell vehicles are replacing electrics in mines and warehouses where engine exhausts can't be breathed. Fuel cell vehicles can be refueled in minutes instead of taking hours to recharge. Fuel cells work for remote sites where there may not be enough sunshine to keep PV batteries charged. Many entities are discovering that they still have reliable power after natural disasters when electrical lines are down and their diesel generators run out of fuel after three days.
ICE (Internal Combustion Engine) Conversions - Although hydrogen fuel cells are twice as efficient as internal combustion engines, they are currently too costly to replace new gasoline and diesel engines. However, there are still one billion ICE's in the world that could be converted to run on clean hydrogen. Although the technology is available, the lack of a hydrogen infrastructure has precluded a wide-scale conversion industry. Vehicle conversions cost a few thousand dollars, mostly for hydrogen storage; either a compressed hydrogen cylinder, liquid H2 tank or hydride system. A small gas engine can be converted for less than a couple hundred dollars. The AHA plans to restart our weekend hydrogen production and conversion classes and we encourage entrepreneurs to develop conversion kits. When we start asking for clean air, the market will start delivering the hydrogen.
Oxy/Hydrogen Welding - Gas torches are very useful tools for welding, brazing, cutting & bending metal and loosening stuck parts. Oxy/acetylene torches are most common, but oxygen/hydrogen is used for underwater cutting or in welding aluminum, making precious metal jewelry and glass-forming where the carbon soot from acetylene can not be tolerated. Hydrogen can be used several ways - burning H2 from a single cylinder in air, burning H2 and pure oxygen from cylinders and burning HHO from an on-demand water electrolyzer. Unlike the bright orange and blue flame of oxy/acetylene, hydrogen's pale blue flame can be hard to see. You quickly learn to detect the flame from the heat waves and to adjust it by the sound. The oxy/hydrogen flame has the odd property of reaching the melting point of whatever it contacts. You could weld a nail to a fire brick. With an electrolyzer, you can make your own welding fuel. The AHA is conducting research in preparation for a hydrogen welding manual.
TESI - Roy McAlister's Total Energy System Innovation is a backpackable up to semi-trailer size renewable energy fueled generator to provide humanitarian relief for disaster areas and refugee sites. Beside making electricity for lights and refrigeration, TESI's produce hot water, steam for kitchens and the exhaust is condensed into distilled water. Initially fueled by hydrogen from a metal and water reaction, a biodigester will produce methane fuel from accumulated garbage, sewage and organic debris.
H2 Buyer's Guide
Alternative Fuels
Alcohol - Besides being a good pain-killer, alcohol can be used as a vehicle fuel. Model T's and Ford tractors were dual fuel (gasoline and alcohol) until 1931 because Henry Ford knew farmers were adept at making 'moonshine' and there was limited rural gasoline distribution. When yeasts consumes sugar, they give off alcohol. Starch or sugar feedstocks such as sugar cane, beets, grass clippings, cactus, cattails, seaweed, old bread, paper, citrus peels, manure, corn stover and fruit squeezings can be used.
The simplified process is:
1. Grind the stock and make a water slurry.
2. Heat to kill unwanted bacteria and add enzymes to break the starch chains down into sugar molecules.
3. Add yeast to the cooled mash. Yeast digests the sugar and produces alcohol and carbon dioxide. C6H12O2(glucose) -> 2C2H5OH(ethanol alcohol) + CO2. The CO2 is vented.
4. Decant the liquid for distillation. Heating to 173 degrees F will evaporate the alcohol and leave the higher boiling point (212 degree) water behind. The solids left behind are still rich in protein, minerals and vitamins and be be fed to livestock or replaced into the soil.
If you have a local raw material supply, an
alcohol enterprise can help your community become more energy
independent. Also alcohol burns much cleaner than fossil fuels. Don't even think of making 'liquid sunshine' without an easy-to-obtain permit from the federal Bureau of Alcohol, Tobacco and Firearms.
Biogas (Methane) - Simply put, biodigestion is assorted bacteria turning yesterday's bean burrito into a fart. Organic garbage thrown into a landfill or sewage in a water treatment plant also keep microbes well fed and, until recently, the methane by-product was considered a nuisance and often flared off. Dead micro-organisms decomposing on oceans bottoms have created enormous deposits of frozen methane. The actual chemistry inside any anerobic digester is mind-boggling complex, but if the ratio of carbon to nitrogen is right and the pH is right and the temperature is right (about 95° F), then the bacteria will make plenty of gaseous methane fuel that can be used in your vehicle or generator, used for cooking or water heating or used as a feed stock for liquid fuels. A rule of thumb is that the manure from 5 chickens can produce enough methane a day for a families cooking. A biodigester on a 10,000 head dairy farm would eliminate odors and reduce fuel and electricity expenses. As a bonus, you can electrolyze the slurry and then use everything leftover for an excellent fertilizer.
Biodiesel & Algae- Vegetable cooking oils can be substituted for petrodiesel in engines. The problem is that veggie oils thicken as they get colder and can't be pumped. A solution is to store the vegetable oil in a separate tank, start the engine on regular diesel and then use engine heat to thin the vegetable oil. Another solution is to make biodiesel. The fatty acids in vegetable oil are chemically broken apart with a catalyst (KOH) and then recombined with methanol to form a much less viscous oil. Biodiesel burns cleaner than regular diesel and engines last longer. Algae has a huge potential as an oil supply, because up to half its mass is oil. Although algae flourishes in aquariums, large-scale cultivation is still being developed.
Solar Heating & Cooling
Solar Cooking- A solar oven isn't as convenient as a microwave, but knowing you cooked a meal with free solar energy adds flavor that no microwave can. There are two styles of solar cookers. A parabolic mirror concentrates sunlight directly on food such as a hot dog or on a cooking container. A mirror can be made with cardboard and aluminum foil. A solar oven is an insulated box with a glass cover. Aluminum reflectors focus solar rays inside the box and heat the interior with the Greenhouse Effect. Sunglasses are an essential utensil for any solar cooker. There are a few cons to solar cookers. They won't do much cooking if it's cloudy or even hazy. They work best from about 10am to 4pm, so don't plan a solar breakfast. Tracking the sun gives better results. Manually aligning with the sun every two or three hours is adequate. If you're working, aim the cooker towards the noon sun and you'll still come home to a hot dinner. If the oven is tipped too far, soups and juices can spill. Installing a gimbal will eliminate this problem. The low temperature, slow cooking makes the extra effort worthwhile. Foods don't dry out and burn. It's good for baking potatoes, soups, roasting chickens and casseroles. In hot climates, cooking outdoors keeps heat out of the kitchen. Fresh-baked bread on a camping trip is unforgettable. Solar cooking is fun and so is watching your utility bill shrink.
Solar Hot Water and Distillation- Anyone who has ever left a garden hose in the sun knows the water can get scalding hot. Heat from the sun is free. A practical and reliable SHW system needs to be a little more sophisticated than a garden hose. Hot water has to be stored and auxiliary heating and freeze protection need to be provided for when the sun is down. Commercial systems can cost thousands of dollars and pay for themselves in about 12 years. You can purchase kits or, if you're willing to do your homework and have some basic plumbing skills, you can build and install your own. A solar still is a waterproof box with a sloping glass lid. Solar heat evaporates the water which then condenses on the glass and runs into a collector. Contaminants are left behind. A still provides mineral-free water required by electrolyzers and can purify water in an emergency.
Absorption Refrigeration - Conventional refrigerators and air conditioners require large amount of electricity to compress the refrigerant gas. Absorption cooling uses a different cycle driven by heat. Recreational vehicles and off-the-grid homes often have absorption refrigerators using a small propane or kerosene flame. Solar hot water is also hot enough to make them work. There is an appeal to cooling with heat, especially here in Arizona, but the small demand keeps equipment cost too high.
Materials
Carbon- Every time you burn a gallon of gasoline or take out the trash, you're throwing away half the product you paid for. You're wasting the carbon. Carbon is a wonder element; stronger than steel, lighter than aluminum and conducts heat better than copper. Diamond, carbon fiber, graphite, activated carbon and biochar are already valuable carbon products, but new forms like fullerenes, buckyballs & buckybowls, carbynes, graphene and nano tubes/rods/ropes/buds/foams are being discovered and turned into useful and profitable materials. Carbon can be extracted from the CO2 in the atmosphere or from methane (CH4) biodigested from biomass waste.
