• Why Don’t We Have Functional Biofuel Yet?
    15 replies, posted
https://www.youtube.com/watch?v=LEepDbZqFmE
We... We do have biofuel? Almost all gasoline has ethanol in it, and E85 is straight ethanol, which we get from corn. Not only that, diesel trucks will run off of any kind of veggie oil, with the right modifications.
E85 is 85 (ish) percent ethanol. It's only good for a month or so in your tank, and it can thicken in extreme cold. Not like diesel, but it's not ideal. Other than that it's pretty good for any car that can take it where you frequently fill up the tank. Very high octane too, makes great racecar fuel. Some people run E90 (ish) but it's not feasible to run E100 really. Gasoline's various components and additives are necessary to keep your fuel system in good shape.
this is why im not worried about gasoline going, my cars just gonna start going faster when all we have is e85
Ooo, I didn't know that. I thought the 85 in E85 was the octane rating.
Ethanol does "hold up," but it's not 100% suitable as a drop-in replacement for gasoline due to it's lower energy density and much higher octane rating. It may be chemically incompatible with some materials used in gasoline fuel systems, depending on the engine in question. It has a lower energy density than gasoline, but because of it's higher octane rating, if you have an engine specifically designed to use ethanol, you could make up the difference by having a higher compression ratio, so you'd have better efficiency, torque and power to make up the difference.
this is only partially true for older cars in particular. Anything remotely modern sold as compatible with E85 will have some sort of sensor to gauge the ethanol content and increase the fuel delivery to compensate
Do you have E10 fuel in the US? Over here you can get regular unleaded petrol in various octane ratings, E10 which has basically the same performance as standard 91 octane unleaded but is slightly cheaper or E85 that's high performance. Makes it more obvious that the number is the average percentage of ethanol content in the fuel.
Yeah, most of our stuff is 10% ethanol. It's still labeled on pumps as 87 and 91 or 93. It just has a little disclaimer on the pump that says "contains up to 10% ethanol." There are still places that sell non-ethanol gas though, mainly for lawn equipment or older cars though, and those pumps are few and far between, with a considerable markup.
Kwik-Trip and some Holiday stores only sell non-oxy (no ethanol) premium and I don't run it because rumor has it it's no good for my bolbo, no price difference really. 93 is really only at BP in MN, and they are always more expensive
Unless you're aware of some engine technology that I don't know of: compression ratio is mechanically fixed. It relies on the machined dimensions of the pistons, rods and cylinder. As far as I'm aware, "Flex-fuel" cars do not have any means of adjusting compression ratio, they only adjust spark timing and enrich the fuel mixture to compensate for ethanol's lower energy content. Ethanol has about 66%~ the energy content of gasoline, so unless compression ratio and fuel mixture have been designed so that the engine can have a lean fuel mixture and better fuel efficiency (by increasing the CR), then you will always use more liters of fuel per kilometer, in comparison to gasoline. In the simplest sense, if you're having to squirt more ethanol into each compression stroke, then obviously you are going to use a larger volume of fuel to drive the same equivalent distance, OR the engine will use the same amount of fuel, but produce less horsepower and torque as a result. Unless all of these new engines you're talking about have some sort of variable compression ratio, then they are not physically capable of using ethanol efficiently, in comparison to gasoline. To get the same fuel economy by volume, you would need to increase the engine efficiency. To do that, one would need a higher compression ratio, and a leaner fuel mixture. Neither of which is done by flex-fuel vehicles; they have been designed for gasoline first and foremost, they can "use" ethanol, but they don't use it efficiently.
the reason why we don't have biofuels is because you can't get something for nothing. oil is such a dense powersource. Trying to get algae to deliberately generate such energy intensive molecules on a large scale just isn't possible yet.
Well, it is possible, but all of the legwork you need to do requires a lot of energy input. Making ethanol is a slow and inefficient process. With fossil fuel, most of the work done to produce the hydrocarbons was done by the sun, the organisms and the earth, millions of years ago, and it only needs to be dug up and refined. For climate change, digging up old solid or liquid carbon and blasting it into the air is not a good idea, but it's hard to argue with the fact that it's very cheap to do. I think at this rate we're likely to see synthetic gasoline become a mass-market commodity before pure biofuel takes off as a fossil fuel replacement.
I forgot to clarify that I know very well that E85 kills fuel economy, woops vv It's definitely not perfect, or ideal for every situation. From a consumer/car guy standpoint it's very much worth using if you can put up with it. Maybe not for cars that chug 87, but for any high compression or forced induction setup it's a boon, more octane is always good in knock-prone setups. The cost of E85 where I live is proportional to the efficiency loss compared to 91/93 so it's not a bad deal for me, but my old car would need a whole new fuel system to tolerate it. From what I've read fuel economy decreases by about 30% because you're just pumping that much more fuel. Surely modern cars engineered for E85 use were designed with all its limitations in mind, and with larger injectors than necessary for gasoline and electronically-controlled-everything they change fueling and timing dynamically based on conditions including the (very variable) ethanol content of the fuel. A few cars can even see small power gains on stock tunes because the timing can dynamically advance beyond what it can on comparatively low octane gas, probably not your mom's flex-fuel impala though. It's worth noting we produce a shitload of it domestically using domestically grown corn, which puts a lot of the money back into the local economies. I live in a place that grows a lot of corn, so it's been good to us.
Yeah, I'd just say my gripe is that as long as gasoline is treated as the main fuel source, engines will be built mostly for gasoline efficiency, not peak ethanol efficiency. With all the facts in mind, the "ideal" ethanol engine would be a small displacement engine that is aggressively turbocharged. A smaller engine would have reduced weight, making the car lighter, and the turbocharger could be used to increase power output to that of a larger engine, and things could run a bit lean to increase fuel efficiency. Ethanol runs cooler and is highly resistant to knock, so ideally that could be exploited to produce a really efficient engine because you can manage huge boost pressures. Basically, Ford tried this approach to fuel economy with their EcoBoost engine line, but they sort of failed to deliver on fuel savings because low octane gasoline was causing engine knock. How do you solve engine knock? Well, one way is to inject more fuel to cool the charge... So basically the potential gas savings of turbocharging a small engine, flew right out the window. But ethanol, that could realize the potential of efficient turbocharging. The way things are now are just not exactly favorable for ethanol, in comparison to gasoline, is what I'm saying. It's always going to be treated as the secondary fuel, with far less consideration paid to it's efficiency.
Honestly can't blame ford for johnny dingus not reading the manual and running premium like they tell you to. New cars can survive on it but they detune themselves and are still prone to issues. My car will just knock to death on 87, and many FI/hi-comp cars suffer that fate because of shit owners.
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