Filed under: Biodiesel, Emerging Technologies, Etc., Ethanol, EV/Plug-in, Vegetable Oil, AutoblogGreen Exclusive
Pick of the Fuel Litter - Part 1
"Mirror mirror on the wall, who's the fairest fuel of them all"? The magic mirror in the fairy tale had it easy. Snow White was a shoe-in. In the 2006 Alternative Fuel Beauty Pageant, we have a tougher time picking a winner. Lots of conflicting information. Which one is the "fairest fuel" to put in the tank (or battery bank or fuel cell)? I'm here to pick an alternative fuel that's fair to my pocketbook, fair to the planet, and fair to my thirst for performance and convenience.
I narrowed the fuel contenders down to 5 finalists: E85, CNG, Biodiesel, Electricity and Straight Vegetable Oil. I left out hydrogen because it's readily available in fairy tales, but not on Main Street USA. Having owned at least one vehicle running on each of the fuel contestants below - the notable exception being an E85 vehicle - I feel reasonably qualified as a graduate of the school of hard knocks (or is it NOx?) to subject you to my subjective perspective. So which fuel makes a podium finish? Read on after the jump.
- Ethanol / E85
Another E85 benefit I can give a thumbs up is its high octane rating of 100-105. Personally, I'd like to see a dedicated E85 vehicle like the Europe-only, Saab BioPower turbo sedan. It takes full advantage of E85's higher octane rating to kick up the turbo boost pressure and get you another 50 hp vs. the stock turbo engine running on gasoline (91-94 octane). Current flex-fuel vehicles can adjust timing and fuel injection according to the amount of ethanol in the fuel, but they can't kick up the compression ratio. Saab's turbocharger can, in the sense it compresses more fuel and air into the combustion chamber.
Why is this important? Ethanol has a low BTU count compared to the other contestants. It only scores 75K BTU per gallon. Since ethanol's the major ingredient in an E85 blend, the well-documented increase in fuel consumption vs. regular unleaded should come as no surprise. Consumer Reports recently determined a Chevrolet Yukon flex-fuel vehicle achieved 14 mpg on regular unleaded gasoline and only 10 mpg on E85. While this is an extreme example, an increase in fuel consumption of 5-15 percent is typical according to the National Ethanol Vehicle Coalition. E85's skeleton in the closet has been this fuel consumption penalty. As the driving public gets wind of that little wart, flex-fuel vehicles are going to need every tax incentive they can get to sit pretty in the public eye. Saab's BioPower models prove you can have you cake and eat it too - get higher performance while minimizing the fuel consumption penalty of E85 by kicking up the effective compression ration with higher turbo boost.I have to mention the land use debate involving ethanol: can we afford to dedicate enough arable land to raising corn, switchgrass, or whatever the ethanol will be produced from? The jury is still out on that one. Oh, yeah. One more thing. Ethanol's a trifle corrosive, so transport must be by truck not traditional pipeline.
Cynics point to the paltry number of E85 fueling stations in the U.S. There are fewer than 1,000 nationwide with a heavy concentration of those in, big surprise, Midwestern corn-producing states. Minnesota, for example, has over 200 E85 stations with a quantum leap to 500 predicted by 2008.
Predictably, none of these shortcomings have prevented the ethanol-plant-building gold rush that been going on in the U.S. We're looking at a total of 130 plants operating with an annual 4.6 billion gallon capacity by recent reckoning. Quite the pile-on I'd say.
To sum up, ethanol/E85 is renewable, can be domestically produced, has higher octane than gasoline and burns cleaner plus (and this is a biggie) it can be used in existing gasoline vehicles with relatively minor alterations to the vehicle's fuel storage and delivery system.
On the downside, it's energy balance isn't great right now, although it will likely improve as time goes on, and it takes a lot of arable land to grow the plants (be they corn, switchgrass, or sources of cellulose) from which to distill the ethanol. Also in the negative column, ethanol can only be used in a limited way with diesel engines. So-called "E Diesel" is only 10 percent ethanol. Ethanol's high octane rating works against its cetane rating rendering it tricky to use in diesels. But E85's major handicap is higher fuel consumption in comparison to gasoline, diesel, and most of the other alternative fuels. Higher consumption means the price must be proportionately lower than competing fuels to make it worthwhile for the consumer opting for E85 in his or her tank. This means tax incentives must be applied to the equation. Of course, there's no such thing as a free lunch. Tax incentives granted in one area, means another area of the federal budget suffers - at least in the short run. Personally, I can't feel warm and fuzzy about E85, especially in light of the benefits of the other alternative fuels we have available.
- Compressed Natural Gas (CNG)
CNG vehicles have been around for years, but you don't find them at your local Ford dealership. Because of the special fueling requirements (i.e. a pressured filing device with fail-safe fittings rather than the ubiquitous liquid fuel pumps dotting our landscape), CNG vehicles have been solely marketed to fleet owners. It's thought that the centralized fueling of a local fleet lends itself to CNG rather than the individual private owner. I've previously reported on the equipment needed for CNG operation in "the Nuns' story". The Natural Gas Vehicle Coalition website, among other useful resources, provides a list of CNG vehicles for sale. Some of these are dedicated CNG vehicles like my Dodge (i.e. only run on CNG) others are bi-fuel and therefore capable of transporting you and your goods on gasoline or gas of the CNG variety. Dedicated CNG vehicles like the Honda Civic GX sedan can have engines that are optimized for CNG's high octane rating. A bi-fuel vehicle needs to be capable of using the inferior fuel as well as CNG. This precludes CNG-only tricks like higher compression ratios.
I had the distinct pleasure of driving a CNG powered 1994 Dodge Caravan for about two years. The pleasure was two-fold. It was squeaky clean in the exhaust emissions department (lower than an E85 vehicle even) and I got free fuel for a year (that's a story for another time). The weakness of CNG as fuel is similar to that of hydrogen: onboard storage requires bulky pressurized cylinders that take up more space than a typical gasoline or diesel tank. CNG is stored at 3,000-3,600 psi pressure. I added larger than stock aftermarket tanks to my van. Even with those under the floor, my range was only about 275 miles per fill. Better than an electric vehicle, but nothing to write home about. And, no, there's not a lot of CNG fueling stations around which compounds the problem of a CNG tank's short range. I bought my CNG Dodge Caravan with eyes wide open. I had resigned myself to the restricted range of travel. I figured on staying within a 75 mile radius of my local CNG stations. Like a felon on shock probation, I couldn't plan on leaving town for any distant cities.
In summary, CNG, although limited, is domestically available in North America, has higher octane than gasoline and burns cleaner, plus it can be used in both gasoline and diesel engines.
On the downside, it's not a renewable fuel, and it can't be used in existing gasoline vehicles without extensive alterations to the vehicle's fuel storage and delivery system. Its major drawback is lack of fuel station infrastructure. While CNG is piped to most residences in the U.S., a special, pricey home fueling compressor is required for fueling and it takes a long time to fill a vehicle's CNG tank. It's not as simple as adding an E85 liquid pump to your local gas station.
Click here for Part Two of this article where we'll dig into Biodiesel, Electricity, and Straight Vegetable Oil and crown the fairest alternative fuel of them all.
Reader Comments (Page 1 of 1)
Doro 11:24AM (9/27/2006)
And how about the impact of the alternatives on the environment ? Are they pollutants ? If so they are NOT an alternative !
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charlie 1:17PM (9/27/2006)
I know that higher compression ratios can facilitate higher efficiency... I wonder how much more efficient an engine designed specifically to run on, say, E70 to E85, could be over an engine designed to be used with everything from straight gasoline to E85. Something like that would help to combat the issue of ethanol's relatively low energy density.
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Ken Hyde 3:01PM (9/27/2006)
I haven't heard discussion of the carbon cycle, yet. It is, at least theoretically possible, to produce ethanol so that its use effectively creats no net gain in the carbon cycle. Also, re: the mileage difference, tax incentives would only be needed if the price of ethanol or E85 is close to gasoline. If it's substantially less, all you're really talking about is fuel tanks 5 to 15% larger than a gas fueled vehicle. Regarding real estate to grow the crops, you can use less Ethanol with use of Hybrid (or Tribrid) power trains. Then you have an even cleaner burning power plant, also. Very low CO2 emmissions. Seems like a lot left out of the discussion here. The whole discussion isn't just about becoming independant of Petrolium producing states.
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ben 3:33PM (9/27/2006)
Two points on ethanol: 1. You failed to mention the other side of the energy unit ratio, natural gas. This fossil fuel is used to distill the corn. Combine this with decreased mileage and your green factor is minimal. 2. Ethanol distillation uses huge amounts of fresh water. This has already become a problem for some plants in water abundant Minnesota. Economics aside (which aren't great either) I believe ethanol to be a poor alternative.
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Richard 4:13PM (9/27/2006)
Many of the ethanol plants in the midwest are
using coal fired steam plants for distillation.
This coal is being shipped in from Wyoming and
other locations.
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russell geister 7:07PM (9/27/2006)
e85 is not the answer it still requires the use of regular gasoline, but none of the manufacturers have cosidered the reinvetion of the steam engine. which does not have any octane needs just requires something to burn and that can be almost any fuel.if your worried about power,when steam engines were avalabe they were some of the fastest around,just difficult to use but i think these problems can be overcome buy the use of new tec and modern engineering.
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MikeW 12:06PM (9/28/2006)
E70 for winter duty.
Direct injection gasoline engines already have WAY high compression ratios. The Audi 3.1 FSI V6 in A4/A6 has a 12.5:1 compression ratio. Modern diesels are going lower compression ratios and higher boost, ~17.5:1 down from 20 and up :1, the new Audi diesel V12 only 16:1
Maybe ethanol can be used with the HCCI engines that are being developed ~15:1 compression ratio.
Butanol is pipelineable.
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VR 1:48PM (9/28/2006)
In response to Comment 4, point 1:
The "cost" of the natural gas or coal used in making Ethanol is indeed included. It is part of the 1.2 to 1.7 energy unit return, mentioned in the 1st paragraph on Ethanol. For the total lifecycle, it takes 1 unit of fossil fuels energy to make 1.2 to 1.7 units of Ethanol energy. That includes the energy used in refining the Ethanol.
In addition, something that was not mentioned - with good cause, because it is still experimental - is the progress we are making in Ethanol production from gassification, using feedstocks with higher yeilds than corn - or using "second use" products like cellulosic waste. Additionally there has been much progress in the last couple years on removing the Natural Gas or Coal from the Ethanol refining process.
Within 10 years we will have significant Ethanol producation capacity that has a higher energy return, uses less feedtock , uses more "second use" materials, and is cleaner overall.
That is what happens to an industry when money is put into it. The processes get improved. Efficiency improves. Technology improves.
No one expects to be at 1970 technology forever. And when you couple this with improvements to the Ethanol capabale engines - it is win win.
The same holds true for biodiesel. Since the "boom" is injecting money into the industry, there are improvements to the process being made. Faster reactors that require fewer chemicals. Improved yeilds from sources other than soy. improved quality of fuels for better efficiency.
Biofuels using last years technology are *not* the answer - and while they are significantly better than petroleum - they are not a viable long term solution. But biofuels using next years technology are looking bright indeed.
Better to invest our money in future biofuels improvement than in aging oil industry technology and processes that will have to go away some time anyway...
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OhmDr 6:09PM (10/26/2006)
A couple of comments:
1) Ray, you mention that Ethanol is corrosive and this is why it can't be piped... I think your facts are somewhat wrong. It isn't corrosive to metal, but it does "attract" water... Look at a can of HEAT sometime. It is mostly Ethanol. - So, if you pipe Ethanol over a distance, low spots in the pipe may end up with water/moisture deposits, which in turn do equate to rustout.
2) For the people who are burning and churning on needing coal or natural gas to make Ethanol, you are correct and wrong. Like everthing, you must give something to get something. Next point of this is that the entire bushel of corn used in the Ethanol making process isn't used. There are by-products that come from that process as well. These by-products can be sold and used for other useful things, such as plastics, food (animal), and other things.
3) I have a 2000 Plymouth Grand Voyager SE. Bought new, the E85 capability was something that I had on my want list. Sadly, most dealerships had no idea what E85 or Flex-Fuel was, so I was educating THEM... They should have given me a commision... Anyway, off track. - I have run E85 in the van at times, but right now, the cost between E85 and regular unleaded doesn't make it cost effective to run it (.20/gallon difference here). I'm a car nut, I admit it, and I watch the fuel economy of all my vehicles. This van, on E85, take an economy hit of about 19% on the highway and 25% in town. I usually do not drive this van, so I can't say if it would take less of a hit if I was driving.
4) E85 does produce more HP than regular gas... No turbo needed, but it would certainly help more. Whenever I do run E85 in the van, even a half tank of E85 and half tank of regular, my wife knows. She states that the van "leaps" off of a start. - She doesn't care for this.
5) E85 burns cleaner and puts out less pollution than regular gasoline. - This means less air pollution and less carbon and other build-ups in your engine. - E85 also burns at a cooler temp (as already noted) so it puts less stress and heat on the engine block and other parts. - This also means it results in harder starts in the winter.
6) One downside that I do see if E85, which could result in more repairs/damage to an engine is that E85 acts like a cleaning/drying agent. This means that it will clean oil and other stuff off the cylinder walls. If you run E85, you want to use an engine oil that is designed to work with E85, - Chrysler actually has a "code" or standard for this. When I was unable to find anything other than the Chrysler motor oils with this code, I did some research to find out what people who race E85 and 100% ethanol use. The two oils that people kept mentioning were Valvoline 5-30 and Mobile 1 Synthetic. - I use Mobile 1 Synthetic 5w30. My wife doesn't put 3000 miles on the van that quickly... as of today, the van has just over 46,000 miles on it, so I change the oil every 3 months.
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Steve Long 9:49PM (1/09/2007)
Ray,
I stumbled upon your post and thought you might want to know that your old 1994 Caravan is still going strong in California at 150,000 miles. I can see no reason why it won't go 200,000+, as clean as the engine is. I think the Caravan, with the relatively small 3.3L engine, is the best combination of range and utility of the dedicated CNG vehicles out there. It's a shame they stopped making them in 1996. With the CNG fueling infrastructure we have here, I can range fairly easily from Los Angeles to Phoenix, San Francisco, or Las Vegas. CNG technicians for repair are also available, though not exactly plentiful. Fuel cost is a bit higher than other locales, at $1.90/GGE, but who can complain, with gasoline prices where they are. Our governor also just extended car pool lane access for us clean vehicles into 2013 (was slated to expire in 2008), so there's every incentive to keep the Caravan going virtually forever.
Steve
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