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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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  • by lisaparratt ( 752068 ) on Friday December 12, 2008 @04:15AM (#26087503)

    They do. They just don't sell them in the US, because your domestic diesel is dirty filthy stuff compared to that used in the rest of the world, and would foul their fueling systems in no time at all.

  • by Idaho ( 12907 ) on Friday December 12, 2008 @04:37AM (#26087589)

    Sure, bio-diesel is great, but what difference does that make to people running cars dependent on refined gasoline?

    Until either carmakers start to manufacture vehicles that can accept something other than regular gasoline (petrol)

    Uhm, they do?

    Except in America, apparently. Meanwhile in the rest of the world, diesel-powered engines are very common, I think in Europe about 1/3rd of new cars sold run on diesel and will accept this bio-diesel without any engine modifications. For trucks (again in Europe), virtually 100% of them run on diesel and it has been this way forever, since diesel engines have high torque at low RPM and are therefore especially suitable to towing heavy loads.

  • by moosesocks ( 264553 ) on Friday December 12, 2008 @04:39AM (#26087599) Homepage

    We fixed that. By 2010, all US diesel will meet or exceed international standards.

    VW can't sell their diesel jettas fast enough in the US.

  • by Anonymous Coward on Friday December 12, 2008 @05:19AM (#26087737)

  • Re:Citation needed. (Score:2, Informative)

    by phantomlord ( 38815 ) <slashdot AT krwtech DOT com> on Friday December 12, 2008 @06:29AM (#26088013) Journal

    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.

    I'm not sure about where you live, but here in western NY, restaurants generally don't get paid for their used fryer oil. Rather, it costs $35 a month to rent an oil dumpster and to have it emptied (at least it did at the restaurant I managed up until 2 years ago). We had someone offer to take the oil for free from us to convert to bio-diesel, but it actually cost us more money to give it away to him since we had to waste time opening and closing buckets, being sure to carefully pour it, etc. At 10 extra minutes per night (2 employees at 5 minutes each), that's an extra 5 hours (300 minutes) a month at roughly $11 per hour (don't forget the business costs above paid wages to employ someone and NY's minimum wage is higher than the federal one). Further, we had to go through the hassle of keeping a second bucket to transfer waste oil around since we couldn't dump the stuff from the grease traps on the grills into his buckets because he didn't want to deal with separating the impurities.

    What are restaurants going to do? They can't just dump the oil into the garbage (and you don't want to see what happens to your plumbing when you dispose of used oil in a sink) or else the garbage company and environmental agencies will be after you, so they have to pay the disposal fees. The marginal cost is passed on to the customers as part of the cost of doing business. Even if the restaurants got paid by someone picking up the oil, you don't think they're going to lower their prices by that marginal amount, do you? It'll just be a way to make more money (and then we can hear about big chains that have LOTS of oil making obscene profits at the expense of their poor customers).

    Anyway, much like used vegetable oil, there will be increased costs associated with separating and storing a specific waste item. If just 10 minutes a day is wasted on it, then you're just breaking even with your $60 projected revenue stream. In fact, other work that could be getting done is getting delayed in that time (and anyone that has ever worked in, much less managed, a restaurant knows there's always something that can be done). It's just not worth the hassle.

  • by XavidX ( 1117783 ) on Friday December 12, 2008 @06:44AM (#26088101)
    This is kinda interesting from the link you mentioned (

    The manufacture of instant coffee begins with brewing coffee in highly efficient extraction equipment. Softened water is passed through a series of five to eight columns of ground coffee beans. The water first passes through several "hot" cells (284-356F, or 140-180C), at least some of which operate at higher-than-atmospheric pressure, for extraction of difficult components like carbohydrates. It then passes through two or more "cold" cells (about 212F, or 100C) for extraction of the more flavorful elements. The extract is passed through a heat exchanger to cool it to about 40F (5C). By the end of this cycle, the coffee extract contains 20-30% solids.

  • by RustinHWright ( 1304191 ) on Friday December 12, 2008 @07:01AM (#26088203) Homepage Journal

    Sure. In some places. Two years ago or even longer ago. Times have changed since then. Check it out. These days there have been increasing problems with waste oil being *stolen* from behind restaurants. Around here waste oil tanks are chained, locked, and covered in PROPERTY OF.. stickers these days. Certainly, not everybody has figured it out yet but the economics of used oil have changed, even with fuel prices now dropping back down. For a while.

    As for the mechanics you're talking about, just like anything else, a new approach is taking a while to get new infrastructure. Waste oil containers *designed* for transfer. Sealed transfer means that are more like the effluent pipes for a motor home than like the kind of manual lift, turn, and scrub you're used to. Catalysts to reduce residue in tanks. Spinner filters that push all that goo out of the way with far less use of consumables.

    This kind of thing not only has to deal with half a dozen categories of health and safety regs, it also gets alternately obstructed and improved by big, semi-monopoly firms like Waste Management. But it's also being addressed by more engineers and private designers than the Manhattan Project.

    But the bottom line is that these kinds of things are very new and to judge long term viability, let alone net pricing, based on the cobbled together amateur hour stuff you're talking about is like judging what a PC can do based on a badly soldered Altair. Demand is there. Supply is there. McDonalds and the other fast food chains, plenty of non-profits, and several hundred governments are funding the creation of better ways to do this. In fact, McDonalds has been selling their waste oil in Europe for quite a few years now. For, mind you, a hefty profit.

    Oh, and fwiw, I'm well acquainted with the mechanics of this. I was just pricing retail space last night, I've been through quite a few waste oil facilities and have gone over things like transfer techniques, residual water percentages, and so on, with people up to and including the head of process engineering for Kettle potato chips and various demand side folks in both east and west coast biofuels processors, including ones from near you. Just talked last month with the New York State head of such things a few months back about the lack of publicity the NY State programs done upstate under Pataki got. I think that you'll find that Patterson will change that.

    It ain't over yet, dude. And if you check into petrochemical processing from a hundred years ago you will find that it was messy, awkward, wasteful, and far more dangerous. These things take a little time. And they're improving fast.

  • La-dee-dah (Score:3, Informative)

    by shking ( 125052 ) <> on Friday December 12, 2008 @11:13AM (#26090455) Homepage

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

    Approximately 2 gallons per car in the USA, or one gallon per American, or 1 liter per "first world" citizen (N.America, Europe, Japan and a few others)

  • Re:Whoa, whoa, whoa (Score:3, Informative)

    by MikeURL ( 890801 ) on Friday December 12, 2008 @02:26PM (#26093491) Journal looks a lot like the Idiocracy. No one understands net energy so JUST crowing about using coconuts seems like an achievement if you ignore that it took a mountain of empty barrels of oil to get him there.

    I'm hopeful that having a physicist as Secretary of Energy is going to help make a difference. But the political momentum still seems to be toward cosmetic change that is a net negative energy balance (with corn ethanol as perhaps the most spectacular example).
  • by babyrat ( 314371 ) on Friday December 12, 2008 @04:11PM (#26095009)

    The whole point of this article is the production of biofuel from WASTE.

    You are correct if you need to grow something for fuel in lieu of food, but if you are taking something that simply goes to landfills and instead turn it into fuel, you avoid all those problems.

    Seems like a good thing to do while we are working on better longer term solutions.

Beware of Programmers who carry screwdrivers. -- Leonard Brandwein