UPDATE:
Lab tests show the problem was may be caused by paraffin wax – a derivative of Diesel Fuel. See this report:
http://nbb.grassroots.com/resources/BloomingtonBusReport.pdf
This bus design does not allow for heating of the filter by the engine.
h/t to Kum Dullison
UPDATE2: There is new information, from E.M. Smith in comments, citing that possibility of “methylester that solidifies at >10F vs Paraffin wax” could be a contributor. The lab did not test for that, so the question of fuel quality remains unresolved.
==========================================
Excerpts from the Minneapolis Star Tribune, January 16th 2009
Biodiesel fuel woes close Bloomington schools
“All schools in the Bloomington School District (Minnesota) will be closed today after state-required biodiesel fuel clogged in school buses Thursday morning and left dozens of students stranded in frigid weather, the district said late Thursday.
Rick Kaufman, the district’s spokesman, said elements in the biodiesel fuel that turn into a gel-like substance at temperatures below 10 degrees clogged about a dozen district buses Thursday morning. Some buses weren’t able to operate at all and others experienced problems while picking up students, he said.
We had students at bus stops longer than we think is acceptable, and that’s too dangerous in these types of temperatures,” Kaufman said.”
. . .
The decision to close school today came after district officials consulted with several neighboring districts that were experiencing similar problems. Bloomington staffers tried to get a waiver to bypass the state requirement and use pure diesel fuel, but they weren’t able to do so in enough time, Kaufman said. They also decided against scheduling a two-hour delay because the temperatures weren’t expected to rise enough that the problem would be eliminated.
In 2005, a new requirement went into effect that all diesel fuel sold in Minnesota had to contain 2 percent biodiesel. Kaufman said that some school districts keep their buses in temperature-controlled garages, and that the First Student bus service, which contracts with several metro-area school districts, keeps its buses in garages or idles them through the night.
Meanwhile, in other news:
Minnesota Boosts Biodiesel Initiative from 2 to 20%
(h/t to Popular Technology)
“or idles them through the night.”
Now that is a clever way to limit GHGs – mandate biofuels and then run them longer!!!
All they need to do is light a small fire under the busses to melt the fuel, Just like the russians do in siberia!
This is probably something that could be resolved by a clever mechanic. There are inline fuel warmers on the market, and I imagine probably a product to keep the tank warm as well.
So in order to save fuel = energy, the buses idle ALL night or live in temperature controlled = heated garages. Great fuel savings !! but then in this era of “Global Warming”, what official could have forseen cold temperatures during winter in Minnesota ? – sarcasm off. It seems that the Law of Unintended Consequences turns every attempt to change what already works around to bite the originator in the rear.
There’s nothing like carrying out a risk assessment before implementing a policy that could put children’s lives at risk. But politicians can’t worry about chidren’s safety when they’ve got to save the planet.
In defense of Bio-Diesel regular diesel will also gel at about 12F due to the paraffin content.(Based on Number 2 Diesel), now the article does not quantify it but being in the US I suspect the temperature was 10F were occuring as well due to the statement ” …because the temperatures weren’t expected to rise enough that the problem would be eliminated”
How much heating gas or oil is used to heat the storage spaces for buses, or leave them running all-night so that they can use biofuel?
I guess bio-fuels were engineered for a warmer world.
In defense of Bio-Diesel regular diesel will also gel at about 12F due to the paraffin content.(Based on Number 2 Diesel), now the article does not quantify it but being in the US I suspect the temperature was less than 10F so it was cold enough even for the regular diesel to gel. The introduction of Biodielsel raises the Gel temperature to 20-30F approx. depending on the blended grade, so using the article as a accurate account I suspect that the real story was fuel problems at temperatures greater than 10F were occuring as well due to the statement ” …because the temperatures weren’t expected to rise enough that the problem would be eliminated”
How much heating gas or oil is used to heat the storage spaces for buses, or leave them running all-night so that they can use biofuel?
I guess bio-fuels were engineered for a warmer world.
(Repost due to my irresponsible use of HTML tag identifiers causing a section of my post to be treated as a really big html tag)
The Law of unintended consequences:
http://news.yahoo.com/s/ap/20090118/ap_on_re_as/as_orangutan_s_last_stand
Freezing the nose off a few kids, makes that biodisel go the extra mile….
The image would need to be labeled “Archive” or similiar so we know it is not what it appears to be. Unless Minnesota school buses are labeled in French.
…… “keeps its buses in garages or idles them through the night.”…..
Idles them through the night!!!…. I thought they where supposed to be cutting down on fuel consumption and CO2 production…. This is bloody farcical….. I’ve truly fallen through the looking glass…. The Mad Hatter is running the ministry for energy and environment.
This is the big disadvantage of mixing conventional fuel with bio fuels and a well known problem.
Bus companies transporting people to the winters ports centers in Austria and Switzerland using a bio diesel fuel mix encountered similar problems years ago.
In the case of bio diesel low temperatures cause gelling of the fuel lines, the filters and the injectors and in some cases it even destroys the fuel pump.
If these buses would have been converted to drive on 100% bio diesel, an electric heating system would have been installed to keep the oil liquid at low temperatures.
We have also encountered problems with gasoline that was mixed with ethanol which contains a high percentage of water.
Another problem with ethanol is the lower flame point of such a fuel mix.
It makes the fuel vapor more vulnerable for static electricity igniting the vapor causing possible fire and explosions. This is a serious safety aspect.
What have we learned from these experiments?
DO YOUR HOME WORK FIRST AND LEARN FROM THE MISTAKES MADE BY OTHERS.
A little desk top research works wonders.
Dontcha’ love it?
Governor Tim Pawlenty: “Increasing the level of biodiesel in diesel fuel means that more of our energy will come from farm fields rather than oil fields…”
So, assuming for the moment that we could get all the oil we needed from biofuels {humor me for a moment}, where then will we get our food once we’re energy independent? I know! We’ll import it! What a terrific idea. We can go from being the breadbasket to the world to being the basket case to the world. Will anyone then be able to connect the dots to worldwide famine?
A lesson in physics for the school children.
I seriously doubt that the boneheaded policymakers were not informed of the drawbacks of biodiesel.
But wanting to be greener than the next state….
And that was with only a 2% biodiesel concentration.
“Qu’est-ce que c’est” – “Ecoliers”. ??
Minnesotan – American English?
I Scandinavia we routinely use “winter diesel” during the cold season, i e you mix in some kerosene to prevent gelling. I imagine this would work with biodiesel as well. Though there probably isn’t such a thing as biokerosene.
A passenger airplane recently crashed short on approach – due to fuel starvation. Condensed water in the filters as a result of flying through extra cold air was considered likely. But there was no proof of this cause.
Hmmm… Could it be they’ve been trying out biodiesel in jet fuel? Hope not, but any thoughts?
I have been running biodiesel and straight vegetable oil (and many other exotic fuel blends) since long before they were trendy. Try about 1970 for alcohol blends and about 1980 for funny Diesel.
All these problems are easily solved. All of them are typically not solved and the solutions ignored because you have to know something about fuel; and frankly, folks expect to turn the key and go.
The Problem: The methyl-ester of fatty acids (classical biodiesel) crystalizes or clouds at much higher temperatures than petroleum Diesel. The crystals will clog a fuel filter. This can start happening as warm as 40F, but is usually not a problem until about 20F. Then it gels. The gel stage clogs everything else at about 20F. Notice that these are positive temperatures.
This can be reduced some by blending in a lot of #2 or #1 Diesel. That is the only reason these busses were working below freezing at all, they only had 2% of biodiesel. If the biodiesel is made from animal fats, the cloud and gel points will be much higher.
For regular #2 Diesel the cloud point is about 20F and the gel point about 0F. This varies somewhat with the season and the local refiner (i.e. in Phoenix they don’t remove waxes in summer, but in Wisconsin they will, especially in winter!) For #1 Diesel (which is basically kerosene) you are good down to Alaska temps… but at below -40 you have problems and need fuel heaters anyway.
See: http://www.filtercouncil.org/techdata/tsbs/91-1R3.pdf
or:http://www.greentechvt.com/about+contact/gelpoint.htm
(The first one has 1 bogosity in it. They say to never mix gasoline into Diesel to solve winter issues, yet my Mercedes 240D manual specifically says to do so up to 25%. I’m running 20% RUG [regular unleaded gas] right now.. It depends on your vehicle…)
The Solutions:
1) Run #1 Diesel.
2) Install fuel tank, fuel line, fuel filter, and whatever else heaters.
3) Don’t run biodiesel in the winter
4) Only use biodiesel that is not an ester.
#4 is simple. There are two ways to make animal and plant oils into biofuels. You can react an alcohol, like methanol, with the oil and get a methylester of a fatty acid (prone to gel issues) or you can just dump the fat through a hydrotreater at an oil refinery and get straight alkanes – that is, regular diesel. Both will meet a mandate for biofuels. Esters are warm and fuzzy and you can make them with a tin bucket. The other takes an oil refinery… One ‘feels good’ the other works good.
So, they can solve this by calling up Conoco or Marathon or whoever and asking for biofuels via hydrotreating and be done.
They can put about $400 of heaters into the fuel system.
They can buy real diesel and try to convince politicians that the laws of physics and chemistry ought to override the legislature… Good luck.
Just running the busses to keep the fuel system hot works for small drops of temperature (excess hot fuel from the engine is bypassed to the fuel tank), but at some ‘oh my god’ temperature, the fuel cools enough from tank to engine to gel anyway. That’s what these folks hit. At that time you must have a heated fuel line, tank, and filter or you are going to stop.
FWIW, my Mercedes 300TD says to blend up to 50% Kerosene in the winter while the 240D says up to 25% regular gasoline. I’ve tried gasoline in the 300TD and it gets cranky. Follow the individual engine manual (the 300 is turbo charged and has other minor mechanical differences, but it’s enough.)
I have not yet met a Diesel that didn’t like kerosene or jet fuel in the winter up to about 50% unless the manual says otherwise.
Even the ‘hard core’ biodiesel and straight vegetable oil folks know to back off the mix proportional to temperature, and go all the way to pure dino Diesel in the way cold, or add a fuel system heater.
The standard way to test your mix is to put a bottle of it in the fridge or freezer. Come back and check it each hour or two. If it gets cloudy, you ‘have issues’ at that temperature.
Working Links:
See: http://www.filtercouncil.org/techdata/tsbs/91-1R3.pdf
or: http://www.greentechvt.com/about+contact/gelpoint.htm
Bonus link: http://journeytoforever.org/biodiesel.html
Page 28 of Professional Boatbuilde. Good article about Biodiesel. Highlights all the problems
http://www.proboat-digital.com/proboat/e200812/
The old trick used in the sub-tropical UK was to place an electric light bulb under the engine bay & allow the heat from it to take the chill factor off the oil & water. Not possible now incandescent light bulbs are to be banned!
If the US?? & Europe are serious about reducing car emission among many other things, why do they not regulate the way the Scandinavian countries do by making ALL car manufacturers add COMPULSORY electric heating systems to their cars so that a mains plug in can heat all the oil & water to running temperatures thus saving fuel, most of which is burnt in the all too common short journey to & from work where the cars’ engines get warm just in time to be shut off! Is this the same in the colder parts of the US?
It concerns me that people go on about reliable & renewable fuel supplies when these are based upon crops. Crops can fail you know! With reduced CO2 down to around 200ppm then crops will fail according to some in the know. With a reduced solar output crops will fail too, making a reliable & renewable fuel supply somewhat less than reliable & renewable unless GM to resist cold/heat/dry/wet/reduced solar/disease. A tall order indeed!
Very impressive Inauguration yesterday, well done USA. I sincerely hope President Obama has the wisdom to chose his wise counsel wisely! Otherwise America will go the way of Europe, over regulated, restricted freedom & choice, lifestyles dictated by Political Correctness, etc., & Green/Marxist stupidity, with all that that will consequently engender with
the American people!
BTW it was jolly cold again last night here in the West Country! I expect the Met Office are praying for some warming to get their forecast to average out right for a mild or milder than usual winter, as my wife chisels the ice of her car’s windscreen(shield). Way off target so far.
I was disappointed to hear Obama say yesterday that we should get our fuel in the future from wind, sun and the LAND, that is more biodiesel.
I’m a fan of biodiesel, and I just wonder if the same thing would have happened to regular diesel fuel? I’m not positive this is a fair judgement of biodiesel.
Roger Clague (01:52:02) :
I was disappointed to hear Obama say yesterday that we should get our fuel in the future from wind, sun and the LAND, that is more biodiesel.
I didn’t hear that in the inauguration speech, do you have a reference?
Running engines through the night to prevent fuel clogging, heated wind generator blades to prevent icing, stupid is as stupid does.
We need to get realistic about emissions and start generating electricity from that renewable resource – rubbish.
10 years ago I visited a facility which generated a megawatt from 40 car tyres an hour. The pyrolysis technique kept so2 and co2 emissions within the then in force E.U. guidelines for small scale plant. It is currently legislated off the grid.