Ethanol Powered Aircraft

"Jay Honeck" wrote:

Aside from the obvious stupidity of using more energy to make ethanol
than it actually produces,

There is a certain amount of healthy debate on that issue.

A couple of professors from Cornell and Berkeley have been making that
argument, but the Dept. of Energy has come out with the "definitive"
analysis that concludes you get something like 25 or 30% more energy out,
when corn is used as the base. A higher level of return is projected for
other sources, like switchgrass.

There are still arguments about the DOE study, however.

Most ethanol plants use natural gas in the distillation process, which is
where most of the energy is used, so the production of ethanol is really
a conversion of natural gas to a liquid fuel, with a bit left over.

Since North America is projected to be importing something like 20
percent of its natural gas by 2020, the amount of ethanol reaching the
market will probably drop because of the need to move to more self-
contained production, i.e. using some ethanol to make slightly more
ethanol.

To which I again ask: Where is EAA on this? Why are they washing their
hands of this all-important issue? Are the asleep at the switch, or
simply hoping the issue goes away?

They probably hope it will go away.

We have already been discussing some of the problems with pumping ethanol
through existing engines without making appropriate modifications to
accept the different chemical properties of the fuel. Such things as the
effect on gaskets and synthetic materials, the attraction of ethanol to
water, and potentially increased risk of vapor lock, filter clogging, and
ice crystal development.

One thing I don't think has been touched on is the different physical
properties, which can have significant implications to pilots. These are
that ethanol has about 30 percent lower energy content per gallon than
gasoline, and has about 5 to 10 percent higher density. Think for a
moment what effect these factors have on range and weight limits.

With the lower energy content, range is significantly affected,
particularly for those who use personal margins that are more restrictive
than typical minimums.

The higher density means that even to get that reduced range, you will
have to sacrifice payload to compensate for the added weight of the lower
energy fuel.

As far as EAA's position on the subject, here is a statement from their
web site on what they are doing to influence legislation in various
states:

================================================== ====
EAA Keeps Aircraft Fuel Tanks Full

EAA is focusing its organizational and member resources to head off an
attempt by several states to require ethanol additives in gasoline before
it leaves countless pilots without a way to obtain suitable fuel for
their aircraft.

Legislation being debated in Missouri, for example, would require all
gasoline sold to consumers for use in motor vehicles to contain 10
percent ethanol. Even though provisions are included to allow the sale of
non-ethanol gasoline for use by aircraft, vintage cars, and motorboats,
these aren’t feasible because they could impose financial and logistical
burdens on fuel sellers, including installation of special tanks and/or
requiring potentially expensive special delivery arrangements to ensure
non-ethanol fuel availability.

Instead, EAA is promoting a simple solution based on legislation passed
in Montana, exempting one grade of gasoline—premium grade (antiknock
index number of 91 or greater)—from the ethanol requirement. This will
cover any and all possible combinations of exemptions to this proposed
new rule and allow ethanol-free premium gasoline to be available to all
aircraft, vintage cars, recreational vehicles, etc., at every gas station
in the state.

Idaho and Washington are currently facing Senate and House Bills that
would require all gasoline sold to consumers for use in motor vehicles to
contain 2 percent denatured ethanol by December 1, 2008. Even though
pending Idaho Senate bills include aviation exemptions, EAA feels they
aren’t practical. But aircraft owners in Idaho who rely on auto fuel to
operate their aircraft gained a reprieve earlier this month thanks in
part to the efforts of EAA and its members. As a result, Idaho’s proposed
legislation failed to make it out of a House committee which killed the
state’s ethanol mandate for this session.

In Wisconsin, legislative action to require 10 percent ethanol in
gasoline other than premium grade sold in the state was postponed
indefinitely by a 17-15 vote in the State Senate. An EAA-led provision to
exclude premium grade gasoline was included in the bill’s final version.

EAA is currently engaged in pending ethanol legislation in several other
states, working to ensure that ethanol-free fuel remains widely available
to its members and other pilots who need it.

On Tue, 15 Aug 2006 09:33:50 -0500, James Robinson wrote:

"Jay Honeck" wrote:

Aside from the obvious stupidity of using more energy to make ethanol
than it actually produces,

There is a certain amount of healthy debate on that issue.

A couple of professors from Cornell and Berkeley have been making that
argument, but the Dept. of Energy has come out with the "definitive"
analysis that concludes you get something like 25 or 30% more energy out,
when corn is used as the base. A higher level of return is projected for
other sources, like switchgrass.

I seriously question their results. Pretty much every other study shows,
with current technology, that's pretty much impossible. On top of that,
countries which are currently using agro to produce eneregy have long
since moved from crappy corn to crops that make more sense: sugar cane,
sugar beats, and hemp. Even with these crops, obtaining a return was
difficult.

Beyond that, every study I've read which indicated a return from corn were
torn to bits by other papers, rightfully so, because they ignored huge
segments of the process which chewed up energy to obtain the energy from
corn.

I have to agree, trying to obtain energy from corn is stupid when far
better crops readily exist. Trying to make it work with corn only
translates into higher prices at the end of the day.

Greg

I have to agree, trying to obtain energy from corn is stupid when far
better crops readily exist. Trying to make it work with corn only
translates into higher prices at the end of the day.

.... which is probably the =real= agenda.

Jose
--
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.

In article ,
Jose wrote:

I have to agree, trying to obtain energy from corn is stupid when far
better crops readily exist. Trying to make it work with corn only
translates into higher prices at the end of the day.

... which is probably the =real= agenda.

Of course it isQ
Archer-Daniels-Midland doesn't throw all that money at the politicians
in Washington because it likes them.

Jay,
You know what the real irony is? One of Wisconsin's largest ethanol plants
is located less than 5 miles SW of the EAA headquarters.
Jim

There are several issues here.

Ethanol is politically popular because it is a farm subsidy to an
extent.

Other sources of heat besides natural gas exist for firing alcohol
plants. I would think that burning the corncobs and other unwanted
biomass from the corn itself would be good, as would burning garbage.
But what do I know.

Natural gas is methane, which can be turned into methanol pretty
cost-effectively. Ethanol, despite its poorer power density and seals
compatibility issues, is far more benign and has more energy per gallon
than does methanol. Be very glad you are being required to deal with
ethanol and not methanol.

Everyone knows that materials compatibility has been something doomed
to bite aviation in the ass, hard, for decades. Certificated aircraft
rubber materials have been manufactured since the postwar period with
the same inferior grades of rubbers at great expense to avoid
recertification while everyone else now uses better, more alcoholproof
materials. Dave Blanton told me that in the mid-80s and he was right.

Operation of aircraft on E10 or E15 auto fuel is a different issue
than operating on E85 or E100 with entirely different problems
especially in terms of water separation issues.

The LyCon engines themselves, in terms of top end life especially,
actually like ethanol a lot. Their fuel systems are a different issue.
But I saw an AEIO-540 powered Pitts do an acro routine on straight
ethanol (E100) in the late eighties. The pilot said that the cylinders
lasted a lot longer than with gasoline and all competition acro pilots
would use it if permitted by aerobatic rules.

On 15 Aug 2006 08:15:58 -0700, "Bret Ludwig"
wrote in om:

Natural gas is methane, which can be turned into methanol pretty
cost-effectively. Ethanol, despite its poorer power density and seals
compatibility issues, is far more benign and has more energy per gallon
than does methanol.


How does the energy density of LNG compare to ethanol?

On Tue, 15 Aug 2006 16:40:11 GMT, Larry Dighera
wrote:
How does the energy density of LNG compare to ethanol?

It's less than gasoline, but I'm not sure how it compares to
ethanol... Do you mean LNG or LPG though?

Propane has an octane rating of 110 to 120... Sounds great, right?
Unfortunately, the weight of the tanks is what would probably get
us... Our tanks would have to be built quite a bit sturdier to handle
the increased pressure... Although typical operating pressures are
around 130 psi, tanks are typically rated to over 300 psi...

With LNG, you need either higher pressure or a cooling system...

Here's some info:
http://www.wps.com/LPG/WVU-review.html

Grumman-581 wrote:
On Tue, 15 Aug 2006 16:40:11 GMT, Larry Dighera
wrote:
How does the energy density of LNG compare to ethanol?

It's less than gasoline, but I'm not sure how it compares to
ethanol... Do you mean LNG or LPG though?

Propane has an octane rating of 110 to 120... Sounds great, right?
Unfortunately, the weight of the tanks is what would probably get
us... Our tanks would have to be built quite a bit sturdier to handle
the increased pressure... Although typical operating pressures are
around 130 psi, tanks are typically rated to over 300 psi...

With LNG, you need either higher pressure or a cooling system...


LNG, as used in the Beech system (Beech Aircraft really did the
pioneering work on LNG, of course it went nowhere....) was stored at
very low temperature at approximately atmospheric pressure in a dewar
type insulated tank. It's important to understand that methane-natural
gas- is an incondensible gas for all intents and purposes, like oxygen
and nitrogen but unlike propane, nitrous oxide, carbon dioxide, ammonia
which can be stored at human-habitable ambient temperatures at
pressures feasible for storage tanks.

Methane and propane can be burned in an IC engine in similar fashion
once they are a gas, but at very different fuel-air mixtures. Methane
is approximately 108 octane and propane is in the 103-106 range
depending on exactly what's in it (LP motor fuel is nothing like
reagent grade and contains methane, butane, methanol, and lots of
other junk).

LNG would be practical but the cost of distribution would be high and
the fuel system is fairly complex, at least in the Beech system. CNG
has no range to speak of. LPG is very practical for all sort of ground
vehicles and has been done successfully in helicopters, but large
volume storage in fixed wing aircraft is problematic. A fixed wing
aircraft designed around a fuselage LP tank as a stressed member might
make some sense.

Larry Dighera wrote:

On 15 Aug 2006 08:15:58 -0700, "Bret Ludwig"
wrote in om:

Natural gas is methane, which can be turned into methanol pretty
cost-effectively. Ethanol, despite its poorer power density and seals
compatibility issues, is far more benign and has more energy per gallon
than does methanol.


How does the energy density of LNG compare to ethanol?

LNG has about 73,000 BTU/US Gal., while ethanol has about 80,000. Gasoline
ranges between 110,000 and 125,000.

Keep in mind that the LNG is also accompanied by a very heavy tank, which
has payload implications.