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Power Biotech Transportation

Waste Coffee Grounds Offer New Source of Biodiesel 276

Julie188 writes "Researchers in Nevada are reporting that waste coffee grounds can provide a cheap, abundant, and environmentally friendly source of biodiesel fuel for powering cars and trucks. Their study has been published online in the Journal of Agricultural and Food Chemistry. Growers produce more than 16 billion pounds of coffee around the world each year. Scientists estimate that spent coffee grounds can potentially add 340 million gallons of biodiesel to the world's fuel supply."
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Waste Coffee Grounds Offer New Source of Biodiesel

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  • shipping cost (Score:5, Interesting)

    by convolvatron ( 176505 ) on Friday December 12, 2008 @04:00AM (#26087409)

    how much of it can one effectively suck back from the ends of the capillaries of the distribution system?

  • Re:shipping cost (Score:4, Interesting)

    by ILuvRamen ( 1026668 ) on Friday December 12, 2008 @04:20AM (#26087525)
    from shows I've seen on TV, the idea is for it to be made in lots of local facilities to avoid shipping. It's sort of like future gas stations will make their own biodiesel or at least get it from a supplier within 25 miles in like 80% of populated US cities or something close to that. Also they'd have huge battery banks and solar panels and wind turbines so they could recharge electric cars at very little cost to them. Sounds like they'd make a hell of a large profit by doing either or those let alone both.
  • that's not great? (Score:3, Interesting)

    by CaptainNerdCave ( 982411 ) on Friday December 12, 2008 @04:44AM (#26087617)

    a little less than half of the current demand for fuel could come from waste products, and you're saying that's shameful? improving the processes will only improve the output. increasing the use of diesel will reduce the overall demand for fuel.

    i don't know about you, but if i had the opportunity to turn my various organic _waste_ products into useable fuel, it would be high on my list of priorities. is this being done in europe yet?

  • What would certainly get more expensive is instant coffee, because that doesn't produce waste coffee grounds.

    Eh? Where do you think the rest of those 43 beans goes?

    Spent coffee grounds from the brewing process are the primary waste product. At least one manufacturer burns these grounds to heat water and generate steam that is used in the manufacturing process. The process is designed to be environmentally friendly, minimizing waste products by maximizing the use of the raw materials. []

  • How do they do it? (Score:3, Interesting)

    by Virtually Sane ( 1168935 ) on Friday December 12, 2008 @04:53AM (#26087661)

    OK - so I read the article os I'm not a real Slashdot reader.

    They quote a figure of 11 - 20% oil in the coffee grounds and processing leaves a solid that can be composted. This looks like standard solvent extraction of the oil.

    The scale of the material available is not enough to replace non USA sources of fuel for cars.

    BUT it is a step in the right direction, along with oil from algae, fischer-trope, oil from crops etc. Diversity of supply gives better security and helps keep the money in the country rather than export cash abroad.

    If I were a betting man, I'd put money on small scale (1 tonne/hour) fischer-trope reaction vessels - this can use any waste organic material.

    For the sceptics out there, look at the scale of ALL organic based waste in the USA and then look at the volume of oil that fuel derived by this process could deliver.

    Also in terms of jobs, I believe there may be a number of auto parts suppliers looking to diversify into new industries right about now.

  • Back to the future? (Score:3, Interesting)

    by guacamole ( 24270 ) on Friday December 12, 2008 @04:57AM (#26087669)

    All this talk about biofuel from this and a biodiesel from that leads me to wonder whether some day our cars and homes will be equipped with mini power plants that process organic material, kind of what we saw in the Back to the Future's modified DeLorean from the future..

  • Diesel in the USA..? (Score:4, Interesting)

    by heavygravity ( 160241 ) on Friday December 12, 2008 @05:03AM (#26087683) Homepage
    With all the talk about driving more fuel efficient vehicles and people buying hybrids thinking that they're getting the most efficient vehicle out there, I have one question: why aren't diesels being used in the USA?

    Of course they can be found very occasionally, but they're certainly not mainstream.

    Why a diesel? Well, I drive a 4-year old diesel car. It's a full size car. It uses 5.3L/100km (that means I get 44.38mpg). And I drive like a normal person (or perhaps a little more aggressively). The car tops out at about 140mph.

    This is a run of the mill vehicle - except it uses a 2.0L diesel engine. Why don't carmakers sell diesels in the USA? It doesn't seem like rocket science.
  • by Kupfernigk ( 1190345 ) on Friday December 12, 2008 @05:13AM (#26087719)
    Multi-fuel engines have been around for a while (engine nerds like to restore the ancient Kelvins, which ran on both gasoline and Diesel - but not very well on either.) However, they will never be as clean and efficient as a single fuel engine because the actual mode of combustion of gasoline and Diesel engines is quite different - gasoline burns fast and Diesel burns slow. I remember well the horrible multi-fuel engine of the British Challenger tank, which betrayed its presence with a plume of smoke. A favorite trick of the squaddies was to wait till an MOD official was near the exhaust and then start the engine, covering them in clouds of soot (I've been in a tank when this happened, and believe me it was very funny).

    As noted above, small and efficient Diesels are common in Europe, one reason why our average gas mileage is nearly twice that of the US. The reason for no US sales? Lack of demand, and regulation. US consumers do not like sub-200BHP engines, and the emissions regulations are biased in favor of gasoline. Repeated claims that Diesel particulate emissions kill over 20000 people a year have never been substantiated by proper studies, AFAIK.

    Not bailing out GM could be the most environmentally friendly thing the Senate can do, as with GM and its lobbyists off the plot, there is a chance that the US will adopt a more rational (read German, Japanese or French style) approach to car manufacture.

  • Citation needed. (Score:5, Interesting)

    by RustinHWright ( 1304191 ) on Friday December 12, 2008 @05:20AM (#26087739) Homepage Journal

    I doubt many coffee shops go through enough grinds to make this remotely economical.

    Let's do some rough math. According to TFA, coffee grounds are at least 15% oil. So if a typical coffee shop disposes of 20 lbs of grounds a day, which I would guess is modest, then we're talking about approx. 3 pounds of oil. Are you saying that it will use up a pound or more of oil to transport that to somewhere to process it? And if a coffee shop generates less, why would they have to dispose of it daily? Once they understand it to be a revenue source they will, as restaurants already do about other kinds of waste oil, be more than willing to make the storage space to accommodate the extra income.
    If we assume that retail space costs $4 per square foot (which is a high estimate for much of the country) and that grounds are stored 4' high, then if, say, 20 lbs of grounds are stored per cubic foot, each square foot of space can store at least 12 lbs of oil. Assuming that oil is worth fifty cents a pound and pickup once every three days, then $0.50 * 12 lbs * 10 pickups = $60 net revenue.

    You tell me, is $60.00 bigger than $4.00? It's been a while since I took arithmetic but I seem to remember that this is so.

  • by InakaBoyJoe ( 687694 ) on Friday December 12, 2008 @05:54AM (#26087885)

    .. or you could just leave the grounds out to dry, then toss them into an ordinary furnace. Generate heat or steam or electricity or whatever without the nasty chemicals and energy required to process the stuff into biodiesel...

  • by Soloact ( 805735 ) on Friday December 12, 2008 @06:28AM (#26088009) Homepage Journal
    ...then one would think that the fuel could be made out of all biodegradeable "waste" plant matter. Collecting it would just be a small step for many, as they already sort out glass, paper, plastic, etc, for recycling. Out here, they already have the separate green bins for plant matter recycling. Would also drastically reduce the amount of garbage that people generate.
  • by Alsee ( 515537 ) on Friday December 12, 2008 @06:45AM (#26088103) Homepage

    How do these people think gas is transported now from, say, the Middle East? Magic elf slippers?

    Everyone knows elves go barefoot.
    Oh wait, no, that's hobbits. Nevermind, my bad.


  • by Eunuchswear ( 210685 ) on Friday December 12, 2008 @06:52AM (#26088139) Journal

    Scientists estimate that spent coffee grounds can potentially add 340 million gallons of biodiesel to the world's fuel supply.

    I assume they mean 340 million gallons a year.

    World oil production is around 83 million bbl a day (2004 est.), about 10 times as much (1bbl = 42 gal). So this would keep us going for about two hours and 20 minutes a year.

  • by oenone.ablaze ( 1133385 ) on Friday December 12, 2008 @08:18AM (#26088641)
    I'm wondering whether this production of biodiesel requires different equipment and processes than the filtration of used cooking oil, or any number of other sources. Otherwise, we'd have this expensive, bulky equipment just for purifying coffee grounds, and additional expensive, bulky equipment for processing peanut shells, and any number of other sources, all for producing less than one day's worth of oil demand all year. If the biodiesel is extractable using some kind of "standard method," perhaps the coffee conversion process could follow something like the recycling model--all biodiesel-containing waste products in one bin, plastics in another, etc. But at what level of efficiency could this possibly happen?
  • by TheRaven64 ( 641858 ) on Friday December 12, 2008 @09:58AM (#26089427) Journal
    Actually, both. This is how biogas has been made for decades. Basically, you bury the bio waste with a balloon over the top. Bacteria consume it and produce waste products that fertilise the soil and they produce methane as another by product. You can then spread the solid waste over the fields and use the gas for power. A lot of farms do this, and it's something you can do at home relatively easily, although the amount of fuel produced is not very much.

    During the second world war, a number of people converted their cars to run on gas (which was much cheaper than petrol) and some in rural communities made their own biogas for this.

  • by Silentknyght ( 1042778 ) on Friday December 12, 2008 @10:16AM (#26089621)

    . That is, unlike corn, it's not in competition to food usage.

    Unlike corn-based ethanol. Like the waste coffee grounds, part of the corn (e.g the cob) isn't used for human consumption. It, too, is actively being pursued as a possible source energy. Just an FYI from someone in the field, who is actively involved in these kinds of projects.

  • by TrentTheThief ( 118302 ) on Friday December 12, 2008 @10:52AM (#26090115)

    How many tons of seeds, stems, and leaves are wasted every year?

    Coffee grounds is just another freaking hype buzz word. Henry Ford was using hemp for bio-diesel 60 years ago.

    "Make the most of the hemp seed and sow it everywhere." -- George Washington.

    Get with the plan, people. Don't toss those seeds in the trash, toss them into fields and gardens everywhere.

  • by d3ac0n ( 715594 ) on Friday December 12, 2008 @11:16AM (#26090495)

    No, they don't sell them in the US because the two largest markets, NY and California, have ASININE environmental laws that prevent new diesel passenger vehicles from being sold. (Passenger vehicle being legally defined as a standard automobile or SUV)

    I should know, I ran headlong into these laws just recently. In 2006 I was in the market for a new car. I wanted a Diesel Jeep Liberty. I was planning on brewing my own bio-diesel and getting nice, cheap, environmentally friendly fuel. But I ran into these laws. Apparently it has to do with the NY Environmental air regulations, related to the high-sulfur diesel. Well, the diesel is changing, but Chrysler decided that they couldn't make their diesels efficient enough to meet NY and CA standards (nobody can, the standards are stupidly unrealistic.) so they DROPPED the diesel from their lineup.

    I ended up waiting longer as I heard they were coming out with a new diesel engine in 2008. Well, NY and CA RAISED THE ENVIRO STANDARDS AGAIN, making even the new, Diamler-Benz Blu-tech diesels too inefficient. So Chrysler decided to not even BOTHER adding the blu-tech diesel to the Liberty (and I think they dropped it from all US cars and SUVs). I still wanted a 4x4 to deal with Western NY winters, and the Liberty was still the best bang for the buck. So I ended up leasing a 2008 Jeep Liberty GASOLINE vehicle.

    So, thanks to stupid Enviro laws, I am prevented from buying the vehicle I want, and am stuck driving a less-efficient gasoline vehicle, which creates more air pollution than the diesel vehicle I wanted.

    This is why Big-Govt enviro laws are FAIL. Because there will ALWAYS be some stupid bureaucrat getting some pointless regulation passed which does the exact OPPOSITE of what they intend it to do. Stupid politicians and bureaucrats! GRRRRR! >:(

  • Increased Efficiency (Score:3, Interesting)

    by Nom du Keyboard ( 633989 ) on Friday December 12, 2008 @11:43AM (#26090963)
    And you can increase efficiency even more if you can harness those caffeine overcharged individuals who just consumed the coffee to peddles to help power their vehicles.
  • by sortius_nod ( 1080919 ) on Friday December 12, 2008 @12:21PM (#26091593) Homepage

    Biofuels are no better than fossil fuels - same problem, same outcome. On top of this they are causing massive food issues thought developing countries. People are planting palm for palm oil production (I recently witnessed this first hand, oil palm crops as far as you can see) rather than for food crops. This is why rice is US$700 a tonne in Asia, and other basic staples are getting increasingly more expensive for the people really seeing the effects of global climate change destroy what little they've had.

    We need better fuels - hydrogen, electric with sustainable charging, something like that is going to be better than any sort of "carbon fuel replacement". I think some of us are waking up to this huge issue, but the change needs to come from us as people, rather than through taxing or tax breaks.

  • Starbucks .... (Score:3, Interesting)

    by wtansill ( 576643 ) on Friday December 12, 2008 @02:38PM (#26093651)
    now has a completely new business model and revenue stream...
  • by timeOday ( 582209 ) on Friday December 12, 2008 @03:26PM (#26094299)
    You're thinking too hard. Look, right now, all those grounds go into the garbage. That's the baseline. People who can afford to drink coffee will not quit to save energy. But if somebody can turn a buck buying used grounds and selling them to somebody who turns them into fuel, it's a win. I know a guy who owns a business emptying the lard bins from behind restaurants, and at least part of that becomes fuel. So this sort of thing is not all that far out.
  • Re:Ridiculous (Score:3, Interesting)

    by MikeURL ( 890801 ) on Friday December 12, 2008 @03:52PM (#26094689) Journal
    The problem is that once you break down any program in terms of net energy balance you wind up with a neutral or a negative because you actually need to put in more energy than you get out. It is rare when a recycling program actually provides net energy. But even talking about them gives people "cover" to continue wasteful energy use.

    An outstanding example of using "green marketing" to continue wasteful ways is the Hybrid SUV. People are CONVINCED that they are being green even when they are moving a single person around in an 7,000 lb truck.

    I want every idea subject to very strict net energy balance analysis. I think it is fine if it takes a long time to get to a net positive. The district heating idea you mentioned may take a long time to go energy positive just due to the initial investment in pipes. But I want to see some rational point where it can be shown pretty conclusively that the effort yields ongoing positive net energy compared to the current situation.

    Mind you, some people say by that metric we'd never do ANY alt energy and if you stop to think about that it is pretty freakin scary.

Research is what I'm doing when I don't know what I'm doing. -- Wernher von Braun