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Alternative Fuels

The Ester Machine for making your own biodiesel from waste restaurant oil
Make your own low carbon, renewable fuel by recycling waste restaurant oil into biodiesel.

As with most topics around renewable energy, the discussion should begin with energy efficiency; reduce the use of fuels before investing in a new form of transportation energy. Efficiency is the fastest, cheapest, and most effective way to use our transportation resources. If we can walk or bike to our destination, that will build our health, save us money, and reduce pollution. Mass transit almost always wins over any other form of motorized, personal transportation for low emissions and saving energy. Car pooling or ride sharing can produce a quicker impact on the environment or your wallet than any other miracle technology.

If you are concerned about Global Warming, about a third of our carbon emissions come from our households for heating and electricity and another third from our personal transportation. Cutting carbon emissions from transportation might just be the fastest, biggest contribution a person can make. If we turn to "harder to get" petroleum, carbon emissions from gasoline will go up. Gasoline from Canadian Tar Sand oil, which accounts for 5 percent of our oil, is 14 percent worse in terms of emissions than gasoline from regular petroleum.

If in the end, you still want/need motorized, personal transportation, there are three basic "fuels" that you can use as alternatives to petroleum: biodiesel, ethanol, and electricity.

Biodiesel

The diesel engine was invented in the 1890s to operate on heavier fuels. There is no spark plug or ignition system. Instead, the fuel ignites when spread into the highly compressed air of the engine's cylinders. Because fuel is introduced only at the very moment of combustion, diesel engines can operate on very, very lean amounts of fuel. At idle, a diesel consumes about a third of the fuel needed to keep a gasoline, spark-ignition system operating. Diesels typically provide very high levels of torque (for pulling up a freeway ramp, for example) and deliver about 30 percent better mileage than gasoline engines. Modern diesel cars run very smoothly, quietly, and cleanly.

Running at about half the RPMs of gasoline engines, diesel engines are built very sturdy and typically last about twice as long as their gas counterparts. They cost more to buy but actually are worth far more at resale. A 2003 VW Golf TDI (Turbo Direct Injection) cost $1,200 extra when new but is worth over $3,000 more than the gasoline model after five years.

Most of the biodiesel you can buy in the United States comes from soy bean oil. About 98 percent of our soy crop is crushed to make protein meal for animal feed (not too much for tofu or soy dogs!). After crushing, about 20 percent of the bean mass ends up as soy oil, which is used as an ingredient in many foods and for frying foods in restaurants. In the past, the market for soy oil was small enough that a 300-million-gallon surplus of soy oil was left over after crushing the beans for feed.

Restaurants that fry foods have to change the oil every so often to keep the fried foods tasting "fresh." Every year, about 3 billion gallons of used restaurant fryer oil is discarded. Some is used in pet foods, and some ends up in land fills. There is so much energy left in used fryer oil that it isn't a good choice for composting (gets too hot).

Any organic oil can be turned into a "diesel-like" fuel by a process called transesterification. Organic oils are over three times larger than the molecules in diesel fuels and are too "thick" to be used directly in most modern diesels (with some exceptions for older models). There are typically three hydrocarbon chains linked to a "backbone" of glycerin (like we find in hand soaps or shampoos) in organic oils.

The first step in the process is to break the bonds of these hydrocarbon chains by introducing a strong "base" like Red Devil lye. Once broken loose from the glycerin, the hydrocarbon chains want to re-bond to something. An alcohol is introduced (usually methanol, made from natural gas) and the chains re-bond to the alcohol resulting in a much thinner, very diesel-like fuel. Any water in the chemical process can stop the reaction. The chemistry used is simple, but the lye and methanol must be handled with respect and can be dangerous! Once converted, the biodiesel is very safe to handle, store, and use. The best book on this process is William Kemp's Biodiesel: Basics and Beyond. The effort to collect free waste oil from restaurants and convert it to biodiesel has been likened to the effort to heat your home with wood. It is a hobby and will require attention each week. Restaurants that donate oil will expect the oil to be collected on a regular basis so they can terminate their contract with an oil pick-up service.

The converted biodiesel is so diesel-like that it can be used in many diesels with no modifications whatsoever. Depending on the feedstock (palm oil, soy oil, canola oil, etc.), biodiesel will "gel" or "stiffen" sooner in cold weather than petroleum diesel, interrupting fuel flow to the engine. Generally, people who use high percentages of soy biodiesel blend in some petroleum biodiesel in cold temperatures (about half in fall and spring and from 0-20 percent of biodiesel in the coldest parts of the winter).

No manufacturers offer a fuel system warranty for blends higher than 20 percent biodiesel (Volkswagen limits biodiesel use to 5 percent only for warranty). In spite of the lack of warranty coverage, may biodiesel enthusiasts have operated with 100 percent biodiesel for years with no problems at all. If the lack of engine warranty coverage is a concern, it would be best to purchase a used diesel that is already out of warranty. Perhaps the best vehicles for 100 percent biodiesel use are the VW Beetle, Jetta, and Golf TDIs produced in the model years 1999 ½ through 2003. You should not plan to use biodiesel without doing some thorough reading first to make sure you understand how to use it properly.

Soy biodiesel from virgin soy oil gains about 220 percent more energy from the sun than it takes to make it and reduces carbon emissions by 78 percent. The fuel burns more cleanly and with fewer particulates than petroleum diesel. Engines typically run more smoothly and quietly on biodiesel.

Ethanol

Wood waste at a biomass plant
An ethanol plant in West Burlington, Iowa.

Ethanol has been around for a long time. Compared to gasoline, it is relatively simple to make, safe to store, and humans have been drinking it for a long time. Its chemical toxicity compared to petroleum is hugely different. Gasoline contains up to 4 percent benzene to increase its volatility so it will fire off in an engine. Benzene is a well known carcinogen.

Just like moonshine, whiskey or vodka, ethanol can be made from many different feed stocks (potatoes, fruit, grains, beets, etc.). The largest source of ethanol you can buy comes from corn. Corn ethanol reduces carbon emissions by about 18 percent. Five out of 6 researchers have found that corn ethanol gains about 30 percent more energy from sunshine than it consumes to make. Most of the energy to make it is natural gas for fertilizers and process heat in the ethanol factory, plus coal to make electricity to run the factory. Very little oil is consumed to make ethanol. One BTU of oil is consumed to make 13 BTUs of ethanol (helps with energy independence).

After making ethanol, about a third of the remaining corn mass — known as Distillers Grains — contains all the protein, fiber, and minerals needed to feed to cattle. In fact, about 70 percent of the U.S. corn crop goes to feed animals. Straight corn is an unhealthy diet for cattle. Too much starch in their stomachs over produces acid, creating bleeding ulcers as direct pathways for massive, systemic bacterial infections. As a resuult, more than half of the sodium bicarbonate and more than half of the antibiotics produced in the U.S. are used in animal feed rations.

Ethanol from feedstocks like sugar cane, cellulose, or waste products (like sawdust, wood chips, citrus rind, etc.) have much higher efficiencies returns than corn ethanol. One BTU of energy will deliver about 5 BTUs of gasoline. That same BTU of energy will deliver 8 BTUs of sugar cane ethanol or 9-10 BTUs from cellulosic ethanol. Clearly, we should be accelerating our progress on such fuels.

As a motor fuel, ethanol is over 100 octane vs. 87 octane for regular gasoline. Octane allows engine designers to boost efficiency and power in smaller, lighter engines by increasing the compression ratio. In 2007, every Indy 500 race car ran on 100 percent pure ethanol.

In the U.S., our emissions laws require that if you want to run high levels of ethanol, you must use it in an engineered, E85 (85 percent ethanaol), FlexFuel vehicle. More than 5 million of those vehicles are already on the road. Their fuel tanks, fuel systems, and engines have been designed to resist corrosion from the ethanol (which can attract water or humidity). In Brazil, their flex cars can run on either gasoline or 100 precent ethanol. Since the early 1990s, all cars in the U.S. have been required to tolerate a 10 percent blend of ethanol. E85 FlexFuel cars carry a full fuel-system/engine warranty for operating on E85.

Today's FlexFuel cars were designed to run optimally on 87 octane gasoline and throw away much of the higher work-producing potential of ethanol. Since ethanol contains about two-thirds of the heating value of gasoline, you can expect to get about 25 percent less miles per gallon on E85, which does usually cost less to help make up for the difference. You can make your own ethanol, but you will need a license from the Treasury department to do so. Your own ethanol is exempt from Federal road taxes for up to 400 gallons each quarter. One of the best books on the topic of vehicles and ethanol is David Blume's Alcohol Can Be A Gas!.

Electricity

Wood waste at a biomass plant
The first successful electric car in the United States was built in Des Moines, Iowa by William Morrison in 1891. The four-horsepower vehicle had a top speed of 20 mph and could carry up to 12 passengers. It was powered by 24 battery cells that were stored under the seats and needed recharging every 50 miles.

An electric motor has many inherent advantages over a liquid-fueled gasoline or diesel engine. It produces no exhaust and has very high torgue, which is needed to accelerate from a stop or to enter a freeway ramp. From a dead stop, they accelerate quickly, unlike liquid fuel engines that must "get up the RPMs" to generate horsepower and torque). Liquid fuel engines are actually quite a bit larger than they would need to be just to "go down the highway," mainly to provide enough "oomph" at low speeds to accelerate the vehicle. This causes the entire car to be heavier and larger than it needs to be. Only about 1 percent of the energy from a liquid fueled car is actually used in the end to move the driver to the destination. The rest is lost as heat and to move the vehicle itself.

By comparison, electric motors are inherently simple and have only one moving part: the rotating armature assembly that produces the power. In industrial applications, electric motors can operate non-stop for decades with little maintenance or repair.

In a vehicle with electric drive, there is no muffler, no complicated transmission as we know it, and no clutch. And because the energy of slowing down can be recovered by "regenerative braking" (using the motor as a generator to slow the vehicle), brake pad replacement is extremely rare. You might say that electric drive vehicles are the "perfect way to provide motion" except for the need for an on-board source of electricity. Since electricity commonly comes from an "electric socket," trailing an extension cord along behind you is not a viable option.

On-board sources of electricity can include a hydrogen or ethanol fuel cell, batteries, and/or a liquid fueled generator. The four-passenger Volt being developed by Chevrolet (target date: November 2010) in their "eFlex" approach will have enough lithium ion batteries for about 40 miles of range before the on-board generator kicks in to recharge the batteries on liquid fuel. Even though there will be a small liquid-fueled engine (you can choose from gasoline, ethanol, or biodiesel), the total parts count compared to a conventional liquid-fueled vehicle is estimated to be one third less due to the simplicity of the electric engine. The liquid-fueled engine is never connected to the wheels at all; it simply will recharge the batteries for extended range (estimated at 600 miles before fill-up).

Very few production electric vehicles are available today. There are a few hundred of the Toyota RAV4 EVs and Ford Ranger EV pickups remaining from the time when California required automakers to produce at least a few zero-emission vehicles for sale (these used nickel metal hydride (Ni-MH) batteries. The excellent GM EV-1, a two-seater commuter car, was available only through a lease. When the leases expired, the vehicles were withdrawn from service and destroyed. No one is completely sure why, and GM won't say.

Any existing vehicle can be converted to electric drive and many have been. However, you are on your own for warranty coverage and repairs. Today's conversions typically use lead-acid batteries as newer, high density batteries like lithium ion are not yet mass produced, and the costs are still very high. This means that conversions often have low performance and low range (50 miles or less in warm weather). One of the best books on converting to an EV is Bob Brant's Build Your Own Electric Vehicle.

The national mix of electric generation (coal, nuclear, solar, wind and hydro) means that electricity for an EV pollutes less overall than a liquid-fueled vehicle. In a state like Iowa, where 85 percent of electricity comes from coal, an EV might pollute slightly more.

You can easily make your own fuel for an EV with either solar panels or a personal wind turbine. If you purchase 100 percent of your electricity on a "green contract" (where the utility promises to buy that same amount of electricity from clean, renewable sources), you could be driving around with virtually no air pollution or carbon emissions.

Plug-in Hybrid Electric Vehicles (PHEVs) with modest, all-electric battery range like the Chevy Volt, could have a powerful impact on our dependence on foreign oil. Over 50 percent of the trips in the U.S. are 25 miles or less. Even for trips over the Volt's 40-mile range, the first 40 miles could be on electricity alone. PHEVs with modest battery range could reduce our need for petroleum by 60 percent. Imagine how the price for gasoline would decrease if we cut our demand by 60 percent!

Ethanol

Electric Cars

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