HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  RESOURCE CENTER  |  INDUSTRIES
REGISTER   |   LOGIN   |   HELP
<<  <  Page 3/5  >  >>
NiteOwl_OvO
User Rank
Gold
Re: Biofuel mandate
NiteOwl_OvO   1/24/2013 3:17:59 PM
NO RATINGS
Dave,

Biobutanol sounds like a good alternative to Ethanol and Gasoline. E85b, which replaces the gasoline component with biobutanol seems like a good first step. Also, producing biobutanol from glycerol could leverage existing biodiesel production and turn one byproduct into a useful fuel. More development is needed, but it sounds promising. I look forward to reading your article.

Ann R. Thryft
User Rank
Blogger
Re: Biofuel mandate
Ann R. Thryft   1/24/2013 12:07:56 PM
NO RATINGS
Dave, I'm well aware of fuel mix needs. That wasn't my point: my point is that to be hamstrung by regulations alone, as your comment implied, is absurd. My other point is that we could learn from what goes on in other countries in the world, if we weren't quite so xenophobic. (Ironic, considering how most of us come from somewhere else.) And redesigning fuel systems to deal with ethanol can be done. It's also possible, as we've covered several times, to make biofuel that doesn't require any engine redesign.

Dave Palmer
User Rank
Platinum
Re: Biofuel mandate
Dave Palmer   1/23/2013 2:26:03 PM
NO RATINGS
@Ann: Unfortunately, it's not just a matter of revising regulations.  Most cars (and trucks, and motorcycles, and snowbobiles, and lawnmowers, and outboard engines...) don't run well on gasoline that contains more than 10% ethanol.  There are also problems with material compatability: steel and aluminum components corrode, rubber o-rings shrink, etc.

Redesigning fuel systems to accomodate gasoline with an ever-increasing ethanol content is a challenge, although it can be done. (Obviously there are vehicles already out there that can run on E85).  But then there's the question about what to do about all of the vehicles that are already on the road.

Biobutanol is one possible alternative; it can be blended up to 16% with gasoline, compared to 10% for ethanol.  It also has some other advantages over ethanol.  I'm hoping to finish an article about this in the near future.

Ann R. Thryft
User Rank
Blogger
Re: Biofuel mandate
Ann R. Thryft   1/23/2013 11:45:19 AM
NO RATINGS
I couldn't agree less on the idea of producing less biofuel. That would be extremely shortsighted and shooting ourselves in the foot. Instead, we should revise the regulations. The EU and other countries/regions have similar regulations, they also went through an economic dive, and they might serve as models for what to do, if the legislators in this country can't figure it out themselves.

Dave Palmer
User Rank
Platinum
Biofuel mandate
Dave Palmer   1/22/2013 9:33:29 PM
NO RATINGS
Something that's being ignored here is that the 2007 Clean Energy Act mandates the useage of minimum annual volumes of biofuels.  That is, the U.S. must consume, by law, a certain amount (currently somewhere around 15 billion gallons) of biofuels per year.  The mandated amount is set to increase every year until 2022.

On the other hand, regular gasoline containing more than 10% ethanol by volume can't be sold in most of the U.S. (and most automotive OEMs would like to keep it that way, because higher quantities of ethanol can wreck havoc on fuel system components).

What this means is that we'd better be using at least ten times as much gasoline per year as the mandated amount of ethanol -- otherwise we can't meet the requirement while still keeping the total below 10%.  This is called the "blend wall."

Unfortunately, the amount of gasoline consumed is determined by the state of the economy, which (as you might have noticed) took something of a dive soon after the 2007 law was passed.  The biofuel mandates were never revised to take this into account.

I don't know the exact numbers, but I think we are extremely close to hitting the "blend wall," if we haven't hit it already.  So producing more biofuels right now seems like an extremely bad idea, even if they are being produced from non-food feedstocks.

Tim
User Rank
Platinum
Great Idea
Tim   1/22/2013 8:50:42 PM
NO RATINGS
Any use of non-food product to make fuel can really only be a net benefit to the US.  Local farmers in my state of Virginia do have trouble is discarading the remnants from a corn harvest.  Often times these items end up discarded in the field and turned back in which is not always good for the soil.

NiteOwl_OvO
User Rank
Gold
Re: depends on the cost and the benefit
NiteOwl_OvO   1/21/2013 5:54:56 PM
NO RATINGS
j-allen,


I'm referring to "Thermodynamics of the Corn-Ethanol Biofuel Cycle" by Tad W. Patzek. I do not have the data to say one way ethanol is thermodynamically profitable or not. I only point out that Mr. Patzek states in his paper that various data were from the '80s and '90s. He also chose a point in time, 1973, to base his production costs for nitrogen fertilizer even though based on his numbers those processes have become much more efficient later. In 1973 the energy requirements were 47 MJ/Kg compared to 34 MJ/Kg in 1991 where the data ended. Based on the trend we might see significantly lower energy requirements by 2012.

According to Mr. Patzek, we should stop growing corn for food or fuel. How we grew corn 30+ years ago isn't sustainable.

j-allen
User Rank
Platinum
Re: depends on the cost and the benefit
j-allen   1/21/2013 5:18:29 PM
NO RATINGS
Night Owl,

Thank you for your response to the paper in question.  I was not aware that some of the data were old.  Are you saying that these deficiencies are enough to flip the energy balance so corn ethanol is thermodynamically profitable?  That the sum of fossil fuel imputs ends up less than the enthalpy value od the alcohol product? 

 

Just for the record, my number for the efficiency of PV was just 15% in order to allow for the deficiencies you named.   Is that still too "good" to be realistic, especially when compared to the ~1% for photosynthesis (which also suffers from coludy days)?  

Having worked in the remewable energy industry I sympathize with your friends who have had lousy results with small wind turbines.  Unfortunately not all renewable energy products are built to the best reliability standards.

NiteOwl_OvO
User Rank
Gold
Re: depends on the cost and the benefit
NiteOwl_OvO   1/21/2013 3:52:46 PM
NO RATINGS
j-allen,

Thanks for the response. I read the paper you mentioned. Unfortunately, Mr. Patzek's paper uses 20 to 30 year old estimated data. He also assumes that various chemicals are used, which may not be the case. Also, modern farming methods significantly reduce both soil erosion and the need for some herbicides as well has cutting fuel costs by reducing the number of passes needed to farm the fields. He quotes corn subsities paid to 10% of farmers, which he states were not made public. It would be difficult to check that information. In short, his paper seems a bit biased in my opinion.

Current PV technology is capable of reaching 40% efficiency, however that is under ideal conditions and optimal light exposure as well as using stacked PVs. Dual-axis tracking mechanisms help a lot, but rainy/cloudy days are still a problem. Two people I know have adopted wind/solar power for their homes. They use geothermal heating as well. Unfortunately, their wind generators require constant repairs. Even with solar power to supplement their wind power they have only achieved 34% and 21% of what their respective systems were designed to produce. Maintenance costs have negated any cost savings from producing their own electricity. Maybe someday small wind and solar will make sense, but we're not there yet, so we're at the mercy of the utility companies for now.

Elizabeth M
User Rank
Blogger
Re: depends on the cost and the benefit
Elizabeth M   1/21/2013 5:00:17 AM
NO RATINGS
It's good to hear from someone on the scientific side of this, j-allen! Viability arguments for and against the crop-based production of fuel aside--I think all the debate over this is exactly why it's good a reputable company like DuPont--with a long history of manufacturing a wide range of products--is taking the lead on this.

<<  <  Page 3/5  >  >>


Partner Zone
Latest Analysis
If you've ever wondered how much it would cost to drive to work using electricity as a fuel, the US Department of Energy has an answer for you.
UK-based Plastic Logic and French company ISORG have created what the pair tout as a first in flexible printed electronics: a large area, conformable, organic image sensor printed on plastic.
If the dryer weren't so poorly designed, it would be easier to fix the design problems.
For 3D printing to make the jump from rapid prototyping to manufacturing, engineers will need to find easier ways to move products from their CAD screens to their printers.
Gigabit and PoE are two networking technologies moving ahead in tandem as industrial users power remote Ethernet devices such as IP security cameras at 1,000 Mbps over existing CAT5 cable.
More:Blogs|News
Design News Webinar Series
5/30/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
5/29/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
6/25/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
6/27/2013 11:00 a.m. California / 2:00 p.m. New York / 7:00 p.m. London
Blogs from Our Sponsors
From Dell / Intel®
New Paradigms in Design Work
Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013    5
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
From Dell / Intel®
Increased Workstation Performance Is as Easy as 'DPPO'
Trey Morton, Dell, 4/25/2013    2
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
From Dell / Intel®
Taking Some of the Grit out of Manufacturing
Kirsten Billhardt, Manufacturing Industry Marketing Strategist, Dell, 3/26/2013    5
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Jun 24 - 28, Design Your Own Android App
SEMESTERS: 1  |  2  |  3


DN Radio
Sponsored by
NEXT UPCOMING BROADCAST
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Copyright © 2013 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service