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Brew Your Own Auto Fuel For 41 Cents A Gallon

Iphtashu Fitz writes "Damon Toal-Rossi of Iowa City, Iowa had enough of the high price of gasoline, so it didn't take too much for his friend to talk him into switching to biodiesel, an alternative fuel based on soy or vegetable oil. But after a few months of driving 10 miles to a biodiesel fuel station he decided it was time to start brewing his own. It didn't take him long to find a recipe for biodiesel, and with used cooking oil that he gets for free from a nearby restaurant, he figures he's now getting 44 miles per gallon out of his diesel powered VW Golf and only paying 41 cents a gallon. According to the National Biodiesel Board the number of biodiesel stations in the US rose by 50% last year (to a whopping 200). The president of the American Soybean Association claims biodiesel has almost the same amount of energy as petroleum-based diesel, but cleans an engine's fuel injectors and cuts down on the number of required oil changes. Perhaps these are some of the reasons why diesel powered cars are making a comeback in the US."

55 of 991 comments (clear)

  1. How's it smell? by mdwebster · · Score: 4, Interesting

    I've heard it makes your car exhaust smell like french fries ... Not that there's anything wrong with that ...

    1. Re:How's it smell? by dhovis · · Score: 3, Interesting
      I've heard it makes your car exhaust smell like french fries ... Not that there's anything wrong with that ...

      Actually, there is. If you have complete combustion, then you would not be able to smell the exhaust, you would only be left with CO2 and H2O. If your exhaust smells like the source fuel, then you are putting unburned hydrocarbons into the atmosphere. Unburned hydrocarbons are one of the principle components of smog. Ask anyone who lived in LA during the 50's and they will tell you about how your eyes would start burning when you walked outside.

      Is diesel less expensive to use? Yes. Does it come anywhere near the clean combustion of a good gas engine with a catalytic converter? No. There are some new exhaust systems that bring diesel up to the cleanliness of gasoline, but only if you are using low sulphur diesel, and they add about $3000 to the cost of the car, and are not required yet.

      --

      --
      The internet is the greatest source of biased information in the history of mankind.

  2. Clean?! by AKAImBatman · · Score: 3, Interesting

    claims biodiesel has almost the same amount of energy as petroleum-based diesel, but cleans an engine's fuel injectors and cuts down on the number of required oil changes.

    Have these people seen the crap-for-oil that comes out of most restaurants? That stuff is fully oxidized, saturated with carbon, mixed with salt, and diluted by water! How anyone could expect it to clean anything is beyond me.

  3. The tax man cometh by hwstar · · Score: 5, Interesting

    Don't be too surprised if you find a line on the 2004 state and federal tax return to declare the amount of fuel you brewed so that they can assess back road taxes.

  4. Not viable by Anonymous Coward · · Score: 1, Interesting

    There is not so much waste cooking oil, when compared with the fule consumed by Americas vehicle fleet. Lets not even discuss the enviormental horry that would be the result of trying to raise enough crops to produce vegtable oils for cars and trucks. There is simply nothing harder on the enviorment then the ag_industry.

  5. That's great and all... by nebaz · · Score: 3, Interesting

    But it really can't be a solution for everybody, can it? First of all not everyone has access to a restaurant to get used cooking oil, and last I checked, cooking oil is more expensive at the grocery store than gasoline (I guess it depends on where you live).

    --
    Rhymes that keep their secrets will unfold behind the clouds.There upon the rainbow is the answer to a neverending story
  6. a few caveats by eisenbud · · Score: 5, Interesting

    Biodiesel is cleaner in every respect except that it generates more NOx. NOx and particulates are the primary pollution problems with diesel engines in general, though the industry is making progress. Also, of course, the "free oil from the restaurant next door" solution won't scale, and will probably only last until some entrepreneur starts buying restaurant oil and reselling it to biodiesel manufacturers. That said, the fact that this closes the carbon loop is a huge win, not to mention the potential for energy independence.

  7. Fuel Taxes by Steffan · · Score: 4, Interesting

    Does it take into account fuel taxes? As far as I know, even if you make your own fuel, you're still liable for paying the road use tax that is normally incorporated into the price at the pump.

    1. Re:Fuel Taxes by 17028 · · Score: 2, Interesting

      Umm, has a cop ever checked your gas tank? Anyone? Bueller?

  8. Re:tax? by eisenbud · · Score: 2, Interesting

    I read a news story about people in the UK making their own biodiesel and being harrassed for not paying fuel taxes, but I haven't heard anything like that in the US. Which is not to say that it hasn't happened or couldn't.

  9. Mercedes New E-Class by DaedalusLogic · · Score: 4, Interesting

    Yeah, now that Mercedes has released it's new E Class with a CDI diesel engine you can have your cake and eat it too. Luxury, performance and fuel economy. With 369 lbft. of torque at 1,800 rpm it probably has better than average acceleration for a 4,000 pound car. Even if you don't use biodiesel this is a great fuel saver for luxury car buyers with 37 mpg highway and in the high twenties in the city.

    http://www.edmunds.com/new/2004/mercedesbenz/ecl as s/100359251/roadtestarticle.html?articleId=101837

    And you know what they use to control emissions in the US market with higher sulpher content fuels. A urea injection system... That's right... Urea is sprayed into the mix with fuel and air.

  10. Not In California by gmfink · · Score: 2, Interesting

    The state that could arguably use this interesting story the most will be shut out in another year. CARB has effectively outlawed diesel cars here, due to the higher amounts of NOx and particulates emitted from diesels over gas burners. So actually while this story seems green-natured, California would disagree despite obvious benefits. Are emissions the same coming from biodiesel as petroleum? If so, or they're actually worse, this doesn't seem to have long term viability.

  11. Re:one problem by sakusha · · Score: 4, Interesting

    Even regular diesel fuel engines have trouble in freezing temperatures. Most diesel owners that live in cold weather climates have to plug the car into an electric heater at night if they want their cars to start on a winter morning. Of course there are also plenty of garage fires caused by people who installed the engine heaters incorrectly.

  12. Re:My next truck.. by jdavidb · · Score: 2, Interesting

    Since most cars don't need and can't use anything higher than the regular grade of gasoline, switching to diesel to save money doesn't make much since if diesel is the price of mid-grade.

  13. Re:My next truck.. by kabocox · · Score: 2, Interesting

    Right now Diesel costs about as much as Mid-grade gasoline here in California.
    I'd say check your taxes. I'd bet my 2 cents that there is a CA state tax on Diesel that is intended as a hidden tax on the trucking industry.

  14. Re:More Great News About President-Vice Cheney by Richthofen80 · · Score: 2, Interesting

    But Mr Cheney has not severed his links with Halliburton. Last year, he received $178,437 in deferred compensation from the company.

    what a shoddy piece of journalism. His deferred compensation was coming no matter what.
    Cheney left haliburton's board of directors when tapped for vice president. However, in terminating his contract with the board, he was entitled to severance. he chose to take it over four years instead of all at once for tax reasons. to imply that he 'made' $178,000 last year is incorrect. he had already earned it but took the deferred compensation. He would have got it no matter who got that contact.

    ten points if you can name another company that does what halliburton does, or another company that would take the work. Government work has half the margins of private sector work, its slum and the companies that take it suck. (raytheon is still a bad investment. and no one else makes the exact same missles they do.)

    --
    Reason, free market capitalism, and individualism
  15. Re:My next truck.. by LynchMan · · Score: 4, Interesting

    Actually it sorta does when you get almost double the mileage for the same price.

  16. If you try this ... by porcorosso · · Score: 2, Interesting

    Be careful with the ingredients as these are dangerous chemicals.

    The alchohol and sodium hydroxide needed to crack the hydrocarbon chains creates sodium methoxide that is toxic to your nervous system.

    You probably should wear gloves, wear a respirator, and not get the stuff on your skin.

    You are also still responsible for ~$.50 per gallon fuel tax (depending on where you live) that you would normally pay at the pump.

    --

    Silpon Designs
    Scented Paper Products
  17. Re:Great... by fshalor · · Score: 3, Interesting

    Then you need an:
    a.) Filtering system.

    b.) Luck.

    It would be interesting to test the effectiveness of conventional diesl car/truck filters.

    Also, note:
    2007 Toyota will be releasing a full sized 200+ HP hybrid diesel electric Tundra.

    Sounds like a shoein for the biodeisel market:) I just hope it comes with a stick shift.

    --
    -=fshalor ::this post not spellchecked. move along::
  18. Good for individuals, not practical for society by ProgressiveCynic · · Score: 5, Interesting
    Biodiesel is an excellent option for a few smart individuals who follow this general plan. However, trying to convert a large portion of the national fleet to biodiesel is simply unworkable.

    First, the amount of land required to grow enough oil for all the cars currently operating has been estimated to be about the same amount of land contained in the continental US, and I believe there are a couple of other uses people had in mind for that land too. I've seen similar estimates for the UK fleet vs. UK landmass.

    Second, our current style of agri-business uses large quantities of fossil fuels in the production of crops. Fertilizers, herbicides, and pestidcides are all produced using fossil fuels, and actually require more than a gallon of oil input to generate a gallon of vegetable oil. This isn't really a problem if you're using oil that was already purchased by McDonalds since the oil would have been produced and consumed anyway, but producing biodiesel as the primary aim of the operation is simply counter-productive. Unless you're buying organic biodiesel, and let's face it, there's only so much manure to go around.

    --

    Delivering militantly anti-commercial music to all two people who care!

  19. Before everyone whines.. by Inoshiro · · Score: 5, Interesting

    Remember that while the addage, "if everyone drove these cars, the price of these cars fuel would skyrocket" is true, it ignorse the fact that by having easily substitable goods, you change the price elasticity of demand. Coke and Pepsi share similar prices because Coke knows that if they double their prices, people will just buy Pepsi.

    So while there might be a bit of an increase in the price of diesel or biodiesel, the price of gasoline would be affected as well because we would consume less of it. The more alternatives you have for an activity, the more in touch with reality their pricing is. Take CDs -- their pricing should be dropping because DVDs and video games are (bang for the buck) much more effective. However, because the RIAA is ignorant, they're trying to use price fixing. Naturally, this isn't working as the price elasticity for that good has been increasing in the past few years :)

    Every time there is another way to solve a problem, we all benefit.

    --
    --
    Internet Explorer (n): Another bug -- that is, a feature that can't be turned off -- in Windows.
  20. Here Comes Cheney, BP, and Co. by blueZhift · · Score: 1, Interesting

    This is a good start to reducing U.S. dependence on imported oil and as one poster commented, closing the carbon loop. But I suspect the way this will pan out is as follows.

    Somewhere along the way biodiesel will be a money making concern, then bar the door 'cause here comes Big Oil! Those guys aren't stupid, they know there are only a few more decades of petroleum coming out of the middle east, then game over. So I'm sure they're looking for ways to stay in business, biodiesel may be a way.

    It'll be easier to get people to convert because it doesn't require them to do anything different other than abandoning gasoline engines for diesel over time. And don't worry, the auto companies want to stay in business too, so they'll play ball. The real concern is what things like this will do to the price and availability of food, but given that biodiesel comes from stuff we'd normally discard, the effect may not be much. And of course we still have emissions to contend with, but at least this is a way to get people to use solar energy, so to speak.

  21. Farm subsidies by Anonymous Coward · · Score: 1, Interesting

    Instead of paying farmers to not grow crops due to low prices, we should instead get them to grow soy or other crops which produce biodisel. There will always be a demand or fuel for cars.

  22. Greedy US! by Anonymous Coward · · Score: 1, Interesting

    1 US gallon = 3.7854118 liter
    Where I come fra we pay like $1,5 pr liter and we don't complain. What is it with you americans and free oil??

    No wonder your villige idiot you have selected for president is declaring war against the rest of the world (those who are weak and have some oil)...

    Please, US citizens.. wake up and stop killing our lovely planet.. At some point there is no way back and then it will bee too late.. (and US again go to war for clean air/food/water etc) ... Mod me whatever you want.. but this is reality!

  23. Re:Availability by cmowire · · Score: 2, Interesting

    The problem is that it's still an open question as to the energy efficency of vegetable oil production.

    Like, depending on who you believe, it may require more energy to produce a gallon of biodesel than you'd get from burning the biodesel.

  24. Renewable resource, anyone? by dsinglet · · Score: 2, Interesting

    I believe that much of the attraction of a plant-based fuel is that we can keep making more of it. Petroleum reserves are a large, but finite, resource. Oil-bearing plants of one type or another can be grown in many parts of the world, so there is less of a geographical monopoly on the resource. I'm not terribly fond of tofu, but perhaps I can trick my car into ingesting it...

  25. Diesel's US Comeback? by cb8100 · · Score: 5, Interesting

    True, diesel may be making a comeback in the U.S., but not so in California (unless you count pickup trucks).

    I was in the market for a new car a few months ago and (after renting one in Germany) was very interested in a Volkswagen Jetta. I saw the Volkswagen offered a TDI (turbo-diesel injection) model which had more horsepower, better gas-mileage and lower emissions than the standard unleaded gasoline engine. However, for some unknown reason, the TDI model is not approved for sale or import into California,

    Upon further research, I've found some BMW and Mercedes-Benz models that offer diesel engines (also with lower emissions and better mileage than their unleaded counterparts) that are available for sale in the U.S., but not in California.

    It strikes me as very odd that in a state as liberal and environmentally minded as California, a lower emission engine isn't available in these cars. My guess is that some old-timer remembers the diesels that belched black smoke all day and doesn't realize how many advances have been made in diesel engines.

    --
    My lack of God, it's Trotsky!
    1. Re:Diesel's US Comeback? by ballpoint · · Score: 2, Interesting

      Actually even very modern and recent diesels still spew out black soot, and lots of it, when you step on the accelerator. I've seen a shiny top of the line Mercedes (S class) spewing out that telling black cloud. Not a pretty sight, and if I were the supposedly well-off driver, I would not want to see people around me turn their disgust-showing-face in my direction.

      --
      Flourescent (adj): smelling like ground wheat.
    2. Re:Diesel's US Comeback? by zorkmid · · Score: 2, Interesting

      I have a 2003 VW Jetta TDI (Turbo Diesel). Purchased in Concord California in July '03. The *lowest* mileage I've gotten on it is 49 MPG. I average about 54 Miles to the gallon. No white smoke. No diesel smell. It's got that diesel sound though. Blows away a friends Honda Hybrid. If you push him he'll admit that it's only getting about 35 MPG.

    3. Re:Diesel's US Comeback? by IceFoot · · Score: 2, Interesting
      Bottom line:

      The diesels you drove in Europe were engineered for European diesel fuel, much more highly refined than ours.

      The diesels they sell in the US have old-fashioned polluting engines made for the old-fashioned diesel fuel we refine here.

      Until the US makes better diesel fuel, we won't have better diesel engines...

  26. Re:More Great News About President-Vice Cheney by thomastheo1 · · Score: 3, Interesting

    Besides the deferred salary, he also posesses 433,000 halliburton stock options. Look up the details on google... For the lazy, look here for a somewhat outdated article: http://money.cnn.com/2003/09/25/news/companies/che ney/?cnn=yes

  27. Not a solution by linuxhansl · · Score: 2, Interesting

    I read that in order to supply the US with Biodiesel you need an area larger that the US growing Soy (or whatever you use for Biodiesel). So unless new cars have way better mileage, we are still facing the same problem.
    (The same BTW is true for Solarcells and Windenergy, with the current energy consumption there is simply not enough room in the western countries to supply all the energy).

    It helps, though. Especially because BioDiesel necessarily uses the same amount of CO2 that it sets free when burned, so it wouldn't contribute to the greenhouse effect.

  28. Re:Great... by vbrtrmn · · Score: 2, Interesting

    I don't think it is sold to the grease company, I think the resturants are charged to have it picked up. Quite a good racket, if you ask me, because the grease company refines the grease a bit and resells it to make-up companies. Yes, ladies, that lipstick you are using was once the run-off from a whopper.

    *pukes*

    --
    it's a sig, wtf?
  29. vegetable oil is not petroleum by poptones · · Score: 4, Interesting
    I don't know any places around here that get paid when someone hauls off their used vegetable oil and there's a whole mile of fast food places just around the corner from where I sit. And recycling it is NOT just a simple matter of "filtering it." Vegetable oil is an organic product that does not last forever. It WILL go rancid and using it for cooking speeds up this process greatly. About the only way you could keep up this process of use and recycle is if you were born without a sense of smell (or just without sense period).

    Some used cooking oil does get filtered and shipped abroad for use in food products. But most places I know (including mcd, bk, kfc etc) still have to arrange to have it hauled off and the best they can manage so far is to break even.

    1. Re:vegetable oil is not petroleum by Pionar · · Score: 2, Interesting

      In my high school chemistry class, we made soap and got free used tallow from wendy's (used beef fat from the fries). mix that with something (don't remember - some kind of acid, it's been 7 years - must be why i got a d in chem) and if you get the mixture right - voila! soap! if you get it wrong, it burns.

  30. Clearly wrong - /. May 25 by Anonymous Coward · · Score: 1, Interesting

    Posted by michael on Tuesday May 25, @06:07PM
    from the oilent-green dept.
    Ravalox writes "With alternate fuel becoming a fairly hot trend in recent months, some academics may have applied their theoretical know-how to give us a practical solution. They offer up the idea that certain types of algae are well-suited to biodiesel production as they are nearly 50 percent oil. The article speculates that large pools could be created to farm out biodiesel from algae in areas near waste streams and salt water. They postulate that to replace our fossil fuel usage it would take only a total of a little over ten thousand square miles, which could fit in an area like [less than 10% of] the Sonora Desert."

    http://www.unh.edu/p2/biodiesel/article_alge.htm l
    http://ww2.green-trust.org:8383/biodiesel.htm

  31. Re:Biodiesel - myth? by jfengel · · Score: 2, Interesting

    There is a difference between burning biodiesel hydrocarbons and petroleum hydrocarbons with respect to CO2. With biodiesel, you can recycle the carbon into new biodiesel, so the process can be considered carbon-neutral. It may even be carbon-negative with respect to the atmosphere, since not all of the carbon that gets locked up in the plant is burned in biodiesel; the non-oil parts can be buried or turned into fertilizer.

    As for the cost, well, that remains to be seen. It may or may not scale well. But there are reasons to use biodiesel even if it costs more, reduced net C02 emissions and reducing dependence on foreign oil being the two that come to mind first. It may not totally eliminate dependence on fossil fuels, but even a 10% drop would have advantages over not doing it at all.

    Oh, and I wouldn't call Daryl Hannah washed up. She was just in a movie recently, Kill Bill vol. 1 and 2. You might have heard of it. And she was more of an 80s pinup than a 70s pinup, but she's held together pretty darn well.

  32. Re:Great... by Hard_Code · · Score: 2, Interesting

    Wow. Some responses to all of your responses:

    I'm surprised at the number of 12.5 gallons a year per acre. That indeed seems meagre.

    I'm not suggesting that we don't also need to fundamentally change the weight of our cars and how we travel. That's a lifestyle change that's harder to sell.

    As far as $4.00/gal fuel. It's our own damn fault if we have fooled ourselves into believing we could have, nay, we DESERVED, cheap fuel forever. Europe has much higher fuel prices. We evolved our society in one direction ([sub]urban sprawl/commuting) and they in another (it helps that they are so small and dense though). Cost of travel is going to necessarily change lifestyle habits and the economy as a whole. A hidden cost to "cheap" gasoline is constant entanglement in a volatile middle-east region, a craven betrayal of our own principals to suck on the oil teat of foreign dictators, and a growing number of people who hate us. We've burnt a lot of money in peripheral costs involved in fossil fuels.

    --

    It's 10 PM. Do you know if you're un-American?
  33. Coal is a better answer by Pinkfud · · Score: 2, Interesting
    The Fischer-Tropsch process has been known since Germany used it to provide most of their fuel in WWII. It makes excellent diesel fuel, and can make usable gasoline with some post-synthesis processing. It also gives a host of by-products that find uses in plastics, chemicals, and even cosmetics.

    There are some problems with F-T, and those problems (mostly having to do with environmentally hazardous emissions) are difficult to solve. But that's an engineering problem, and it is within our techno-savvy to come up with the solutions. We need to be doing so! If we keep putting it off, we're going to find ourselves in a helluva fix. It's about time the government funded some serious research instead of handing out "don't worry" panaceas.

    --
    The world is my oyster. That's why it's always in a stew.
  34. Re:Efficency and Yield by linuxhansl · · Score: 2, Interesting
    With just a little help, soy production could be enhanced (along with mileage) to make it a sustainable fuel.

    With the right fertilizers and perhaps some genetic engineering, soy if more feasible than fuel-cells or fusion at this point.

    Maybe, but I doubt it.
    In the end all energy in Biodiesel (and Mineral Oil) comes from the sun. The usable energy in the sun's radiation is proportional to the area of exposure (and of course the angle).
    Now, I don't know the enery efficiency of soy, I also do not know the average energy of sun radiation per areal unit... That would be an interesting calculation... Maybe I have some time later today.
    I know, though, that current Solarcells efficiency is about 30% and there's some theoretical limit around 50% effiency using semiconductors. Also knowing from other research that current energy consumption has to be drastically reduced in order to make solar only energy supply feasible (because of areal limitation on this planet), I have a hard time believing that growing Soy can solve the problem (even IF Soy has a higher energy efficiency, it can't go higher than 100%).

  35. don't need bio diesel by trevorhu · · Score: 2, Interesting

    A diesel engine will run on unmodified used cooking oil. The problem is that it gunks up the engine, but only when it is cool. There is a kit sold by a group in New Jersey (can't find it now) that allows you to start the engine using standard diesel, flip a switch to run on cooking oil, then flip a switch to run diesel through the engine for a few moments before you turn the engine off. no processing, just pour the cooking oil through a stainless steel filter and put directly into tank.

  36. Re:Great... by SunBug · · Score: 2, Interesting

    A manual's greatest advantage (direct link from input to output) is it's greatest disadvantage when towing. If you rev up an automatic transmission trying to get a weight moving, it'll just overrun the torque converter and heat the fluid. If you do the same thing to a manual, fry the clutch and/or break things like gears and input shafts.

    I've seen some trucks rated at ~2x the towing capacity (or more) with an auto vs. manual tranny.

    18 wheelers can use a manual because they're HUGE transmissions, they've got LOTS of gears, and the savings in diesel is worth it in the long run.

    As for parts count, there might be 100 more moving parts in an automatic transmission vs. that of a stick shift, not 10,000 more.

    That said, I've never owned any vehicle with an automatic transmission. Even my gas-guzzling SUV has a manual.

    The CVT is a weird transmission to get used to. It just isn't natural to have the same engine RPMs at 70mph as at 25mph and at 35 and, 45 and..

  37. Re:Great... by marsu_k · · Score: 2, Interesting
    Biodiesel is renewable, yes, but it all has to come from somewhere. How much soy, or what have you needs to be grown to make a gallon of biodiesel? Is there enough arable land to make enough fuel to run the world economy in place of petroleum?
    Quoting from here:
    "Another fact to consider is how much meat we eat. If we feed the grain to animals to produce meat rather than eating it ourselves a large portion of the food energy is used by the animal to stay alive and move around. For example there is a 10:1 conversion factor from grain to beef for feedlot cattle and 50:1 for range cattle. Chicken is produced more economically with a conversion factor of about 2:1."

    Yes, I'm a vegetarian myself, but I tried to pick a quote from a neutral site and am not trying to impose my views upon others. Just a thought.

  38. Re:Great... by poot_rootbeer · · Score: 2, Interesting

    Soy is not the most efficient crop for producing vegetable oil.

    No, but it's a much more utilitarian crop than canola is. Press the oil out of soybeans and you have a versatile and high-protein foodstuff leftover, more than fit for human consumption and part of a healthy diet. I don't know what rapeseed by-products are like, but maybe you can feed them to some hogs.

  39. Re:Great... by Anonymous Coward · · Score: 1, Interesting

    You are probably talking about anhydrous ammonia, which is used as a fertilizer for corn (because it depletes the soil of nitrogen). However, if we switched a lot of acres over from corn to soybeans, we would actually reduce the amount of fertilizer necessary because soybeans are nitrogen producers. The need for anhydrous applications can be almost eliminated if corn and soybeans are rotated every year. The reason that isn't done is because it is more profitable for the farmer to grow corn every year and apply fertilizer. But if there were a larger demand for soybeans, the economics would be different and it very well might be more profitable to produce more soybeans and less corn.

  40. Re:Great... by DigiShaman · · Score: 2, Interesting

    Recycled engine oil get broken down into lighter oils and even fuel. Regardless of the recycled oil usage, as long as it's being used for something, it's better then dumping it back to earth in it's current state. I'm sure some of that jet fuel is made in part by recycled oil from the engine or transmission.

    --
    Life is not for the lazy.
  41. Re:Great... by gotih · · Score: 3, Interesting

    i think he was refering to the filter used when producing bio-diesel.

    biodiesel is routienely stored in plastic containers made of (i think) PETE and all diesel engines in production today are designed to accept bio-diesel by using teflon (instead of rubber) hoses. the main engine concern about using biodiesel is the sodium hydroxide (lye) content of the fuel which can destroy rubber parts.

    when you make biodiesel you wash the fuel with water by misting water into a vat of fuel. the water collects lye as it decends to the bottom of the tank where it is drained out.

    --

    fear is the mind killer
  42. Energy by bluGill · · Score: 2, Interesting

    There are several forms of energy needed to move a car. First is acceleration, f=ma, which is linear, change the force and you change the acceleration. Except we are not working in a frictionless vacuume. So add in friction, which first comes from rolling resistance, and is the biggest factor at low speed. I don't recall the equations anymore, but this too is liniar. Toss in losses from the drivetrain, and essentially you get better milage the faster you go. (some of those losses are constant, things like the alternator) As you gain speed wind resistance becomes the biggest factor, and this is a squared relation.

    Gas milage is an optimization problem. You get the worst at 0MPH, over comming engine loss without doing any work. (work not in the physics sense) As you go faster you get better milage, until wind resistance becomes the biggest factor at which time it goes down. For heavy cars this speed is increased, for big cars it is decreased. (Note, the two go togather) Small cars the speed is higher because of less wind resistance, while lower because of less mass. (again, wind resistance is the bigger factor) Older cars tend to have more wind resistance. A big engine has more internal losses, so this speed is faster, a small engine with less internal resistance lowers the speed. (unless you have a tiny engine this isn't a factor)

    Unless you keep a log and are willing to expiriment it is hard to say more. In general though a new truck will max out at 60 mph, a compact car at about 75mph. However load changes things, truckers have found the max to be 68mph (the company can set the cruise control for the driver) when fully loaded. My geo metro appears to max out at 60 mph (because the engine has to go to less efficant but more powerful modes to maintain faster speeds). My S10 does best at 65-70, in part because of the large engine.

  43. Re:Great... by labradort · · Score: 3, Interesting
    Old oil does break down, but not the oil itself.

    Multi-weight engine oil (e.g. 5W30) is made that way by the addition of polymers that cause the oil to act like the lower weight (5W) when cold and like the higher oil weight (30W) when hot, to provide the best protection at both operating temperature extremes. Over time, contamination and heat break down those modifiers so that the oil is more like the lower weight. That is why frequent oil changes are useful.

    With Synthetics, the same is not true, however, all oils end up getting contaminated with by-products of combustion, and the additives become depleted, making it time for fresh oil.

  44. Re:Already illegal in the UK by cms108 · · Score: 2, Interesting

    i was wondering when someone was going to point this out... there are special police units that go around looking for this kind of thing... (nicknamed the "frying sqaud") - and if you're caught... you can get fined and possibly jail time... and your car taken away.
    check the bbc for details...
    http://news.bbc.co.uk/1/hi/wales/2312521.stm

  45. Re:Great... by jridley · · Score: 2, Interesting

    Yup, and it doesn't have to very new, either. My '97 Taurus has a lockup torque converter. I think they became pretty standard in the early to mid '90's. The combination of that and computer control and integrating power demands such as air conditioning compressor engaging has gotten it to the point that there's hardly any difference in mileage between an automatic and a manual transmission. In fact, unless the driver is pretty good and is shooting for economy, I bet in a lot of cases the automatic would get better mileage.

  46. Re:Great... by whereiswaldo · · Score: 2, Interesting

    The oil was produced by CO2 fixing plants within the last year, you could just burn it and not add anything to the Carbon Cycle (which is why using it to fuel cars is so cool).

    You're missing an important point: you are taking the carbon out of the ground and putting it into our atmosphere. There IS a difference. Plus, this is happening at a much faster rate than would normally.

  47. Re:Great... by pnot · · Score: 3, Interesting

    You're missing an important point: you are taking the carbon out of the ground and putting it into our atmosphere.

    Err. No. You're taking it out of the atmosphere and putting it back in the atmosphere. It's called photosynthesis. That's why plants keep their leaves out in the air, rather than under the ground.

  48. It's illegal here... by HogynCymraeg · · Score: 2, Interesting
    An ASDA (Wal*Mart) in Swansea, Wales, rose the alarm when they had an unusually high amount of oil being sold in their shop. Turns out that it's illegal to use cooking oil as fuel in the UK and I'm pretty sure the USA will catch on to this loss in fuel duty (do they have fuel duty there?).

    The story is here.

  49. Re:Great... by gotih · · Score: 2, Interesting

    here's a summary of the process filtered thru my leaky sive of a brain...

    1. vegetable oil is filtered (filter waste can be composted)
    2. mix methanol with sodium hydroxide (lye) or potassium hydroxide to form sodium methoxide or potassium methoxide.
    3. mix #2 with filtered vegetable oil, agitate.
    4. wash mixture with water by misting water from above (mist washing) or adding water (which settles below) and pumping air thru an air stone (pushing water into the mix), called bubble washing.
    5. settle out the water and sediment
    6. drain
    now you have bio-diesel in the tank. what you drained off the bottom is a watery soap. if you used potasium hydroxide, this can be composted. if you used lye, contact your local municipal sewage disposal people. they will test your stuff. the municipal people said the mix was not very toxic (most of the lye had reacted) and was safe to pour into the toilet.

    one person i know added fragrance and pumice to the soap she drained off the bottom to make a gojo type hand cleaner (great for getting tough grease off).

    --

    fear is the mind killer