COZBY ENTERPRISES, INC.

Biomass for Engine Fuel
July 13, 2010
John A. Cozby

     In 1991 and 1992 Cozby, U.S. Engine, Inc., and Ripley-Burnell Industrial Consultants, Inc. approached the U. S. Department of Energy for help and support in developing high efficiency advanced Rankine cycle steam engines that would use wood or other biomass fuels.  The need is clear for the wood products industry, for remote sites such as Alaskan villages, agricultural applications, and developing countries that have cheap, abundant biomass fuels available.  Because there was no solicitation for biomass fuel steam engines, we prepared an unsolicited proposal to the Department of Energy making the case for the needed development and production of biomass fueled high efficiency advanced Rankine cycle steam engines.

     The need is clearly defined in our letters of support from the wood products industry and the State of Alaska.  (These letters are appended to this section.)  Biomass fueled steam engines were once an important source of power for America and the world.  There is solid historical precedent for biomass fueled steam engine power.  With modern materials and support technology coupled with proper advanced Rankine cycle steam engine designs much better results can be attained than in the past.  Unfortunately, however, the Department of Energy was not interested in, did not care about, nor have any concern for the welfare and energy needs of users in the agricultural community, the wood products industry, The State of Alaska, Montana, or developing countries for superior modern biomass fueled steam engine power.  The many years that the Department of Energy has been stifling biomass fueled advanced Rankine cycle engine development has cost many billions if not trillions of dollars to these users alone.
 
      Biomass fueled steam engines make on site power generation possible in many locations without the need of long expensive transmission lines.  About 40% of the cost of electricity is transmission costs, while the cost of the electricity generated is lowered by using biomass fuel.

      Biomass can power tractors and farm equipment as it once did – only better – and much more cost effective than gasoline, diesel, butane/propane fueled equipment.
 
      Biomass can power irrigation systems directly and on site where needed without costly power lines.

      Cozby has understood the need since the 1960's, but the prestigious Department of Energy does not yet seem to be able to comprehend the issue.  Biomass for fueling engines is an important critical issue world wide which can be satisfied by advanced Rankine cycle steam engine development. 

                                                               July 01, 2010
Ellen Simpson, Executive Vice President
Montana Wood Products Association
1205 Butte Avenue, Suite 5
P.O. Box 1149
Helena, MT 59624

Dear Ms. Simpson:

      We have just read your good article, “Biomass belongs in energy mix”, in The Montana Standard, June 30, 2010.  You state the case very well.
      One of the great needs is for affordable, advanced, high efficiency, high performance engines which can use wood and other biomass fuels.  We first recognized this need in the 1960's and began our search for the best solution.  The best solution is an advanced, high efficiency, high performance steam engine of the advanced Rankine type with a furnace/boiler designed for solid fuels.  Such an engine is the critical missing link for the biomass energy mix and the wood products industry. 

      To begin to acquaint you with us and our company, we cordially invite you to visit our website: cozincmtusa.com 

Thank you, Sincerely, 

John Cozby

Ellen Simpson, Executive Vice President                              July 12, 2010
Montana Wood Products Association
1205 Butte Avenue, Suite 5
P. O. Box 1149
Helena, MT 59624 

 Ref.: Biomass fuel 

Dear Ms. Simpson:
      I am sending you some evidences from my file that confirm your correct contention that “Biomass belongs in energy mix”, June 30, 2010, “The Montana Standard”.  As I said in my e-mail to you, I really appreciated your article on biomass fuel and know it took a great deal of courage to write.
      In 1991 and 1992 Cozby, U.S. Engine, Inc., and Ripley-Burnell Industrial Consultants, Inc. (All Montana corporations) tried to interest the U. S. Department of Energy in wood and biomass fueled high efficiency advanced Rankine cycle steam engines.  Even though we failed to realize DOE support, the need is still real and even more pressing now.  We appear to be the only people that know how to achieve successful development of biomass fueled high efficiency advanced Rankine cycle steam engines for America and the world.  The dates on the letters of support indicate how long the Department of Energy has been stifling the development of biomass fueled engine development to the detriment of the wood products industry.
 Biomass fueled open cycle, inefficient steam engines were once an important source of power for America and the world.  With modern materials and technology coupled with proper advanced Rankine cycle steam engine designs we can do much better than was done in the past.  Perhaps the wood products industry would be interested in this important area.
      I invited you to visit our website, cozincmtusa.com.  Your article in “The Montana Standard” caused me to realize that I should add a page to our website specifically addressing the need of biomass for engine fuel – (if there was an appropriate engine developed that would use biomass).
      I so liked your article that I am asking your permission to put it on our website.  Perhaps we could meet to discuss our mutual interests.  We could come to Helena at your pleasure and convenience. 

Yours, in the fight for a better tomorrow, 

John A. Cozby

Ellen Simpson Ellen Simpsonwoodproducts@mt.net
 
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From: Ellen Simpson (woodproducts@mt.net) 
Sent: Fri 7/16/10 3:30 PM
To:  fbcanaconda@msn.com

Hello John....... I received your request to reprint the biomass piece as it appeared in the MT Standard.  Please feel free to use it as you deem appropriate. 
    The biomass issues are huge and do consume a large amount of time and energy.  The next few weeks are full for me, but perhaps later into the fall there will be an opportunity to get together and hash out some ideas.  Thanks for your kind words on the article and stay in touch.  Ellen

             December 13, 2011
Dear Jukka,
     Yes, you are right, an efficient wood burning steam engine would be interesting.  Very interesting and fill a need.
     You mention Prof. Bengt Johansson of Lund University.  Is that in Lund, Sweden?
     Piston type steam engines can react very fast and very well to changing power loads.  If the system is designed for wood burning, then a dual-fuel/dual burner that will burn either liquid or gaseous fuels for fast boiler response can be installed to supplement and augment the wood burner during such times as need for quick response to load changes or speed changes occurs.  Micro processors would be used to monitor heat requirements and automatically adjust according to need. (The person driving such a car would not be aware of the supplemental fuel use activation.)  A properly designed steam engine will not require electric motors or batteries.  Enough power and speed is inherent in the steam engine itself.
      Yes, wood pellets are a viable and attractive option for fuel if used with a well designed efficient steam engine.
      I hope that this is a help to you.
 Yours, John A. Cozby

Dear John  You wrote:        You mention Prof. Bengt Johansson of Lund University. Is that in Lund, Sweden? Yes.     

      More and more oil producers will realize that their reserves run outone day. They might reduce production or at least not increase it.India and China will increase oil consumption. So price will rise. In Finland forests grow 2177 million m³/year. That could replaceroughly 300 million tons of oil. We use about 11 million tons of oilyearly. We have 0.6% of worlds forests and 0.08% of population. So in future wood will be expensive. Fuel efficiency will be most important feature.   

      Yes, wood pellets are a viable and attractive option for fuel if used> with a well designed efficient steam engine. I agree. Disadvantage is that I cannot make pellets my self. I canmake other types of wood fuel.  

Merry Christmas! - Jukka

Dear Jukka                        January 5, 2012
      Thank you for your recent reply and questions; and HAPPY NEW YEAR TO YOU!

      I have had an interest in Norden – Finland, Sweden, and Norway for a long time.  All three have forests, timber, lumber, and wood industries.  Western Montana, U.S.A., also has forests, timber, lumber, and wood industries.  Many people here use wood for heating and a good portion of them use wood pellets.  Montana has cold winters, spring, and fall.  (Reference my website, site: “Biomass for Engine Fuel” (site 7).

      In answer to your thoughtful question about a wood fueled automobile and the danger of the boiler over heating when the engine stops.  There are six things which address this issue.  You are correct that there could be a potential problem with solid fuel.  To provide for this situation a special design for solid fueled vehicles is required.  Such provision is simple. 

1.     The furnace area is separated from the boiler section.  In normal operation the hot furnace combustion gases flow through a duct to the boiler section generating super heated steam.  When the vehicle stops and steam is not being consumed by the engine a damper in the duct to the boiler section closes and a damper in another duct from the furnace to the exhaust stack opens, dumping excess heat to the atmosphere.  The residual wood fuel in the furnace is allowed to completely burn out to avoid producing smoke (air pollution).  The dampers operate automatically and are actuated by sensors. 

2.    If the temperature and pressure in the boiler continue to rise, a small blower automatically starts and another damper opens to the boiler duct supplying cold air to the boiler area.  

3.    Should the boiler pressure and temperature continue to rise (which is unlikely) there is a high pressure safety exhaust “pop-off” valve which protects from over pressure in the heat exchanger. 

4.    There is still a quantity of liquid water in the boiler tube which also helps to mitigate and buffer such occurrences.  The liquid can absorb a quantity of heat because of the latent heat of vaporization, especially in the cooler end of the boiler. 

5.    The fuel supply, wood pellets, is immediately cut off.  The furnace is designed to contain only a small quantity of fuel at any given time.  The fuel is fed to the furnace by a variable speed auger according to heat demand.  The furnace/combustion chamber is small and the quantity of fuel is small so that there is not a large amount of residual heat to deal with.  Also, the furnace blower supplies enough air so that the fuel burns completely and cleanly.  For furnace start-up, a liquid or gas fuel is employed to bring the combustion chamber up to heat before starting to feed the wood pellets.  This is in order to avoid initial smoke so that there is no air pollution associated with start-up.  Liquid or gas fuel start-up also reduces the time required to get the boiler up to drive away pressure.  Gasoline or propane can be used for start-up purposes.  The gasoline or propane is also then available to augment the wood pellet heat when a burst of power or speed is needed during normal driving. 

6.    The system can be designed so that the engine will continue to idle until the boiler has cooled to the point that there is no longer a danger to the heat exchanger.  In such a situation an automatic transmission would probably serve the purpose best. 

      There may be other ways to address this problem which I have not thought of yet, but I do hope that this is helpful.  I am so slow and I can’t think of everything — Sorry. 

     The same principles apply for other solid fuels including coal.  Coal has its own set of problems and is a separate subject. 

      Speaking of Sweden: Sweden has very admirable engine and automotive industries.  Historically, Sweden has been at the forefront of steam innovation and development.  In 1896 Carl Gustaf  Patrick De Laval designed and operated a complete power plant with initial steam pressure of 3,400 lb.  Very impressive.  The Swedish Mausers are some of the finest rifles ever built and the 6.5 X 55mm cartridge is one of the world’s best.  They date from 1894 and 1896. 

      About Hybrid technology: Yes, a small advanced steam engine can be used in place of a gasoline engine.  The steam engine would be a better choice for several reasons.  If a hybrid system is better, then a hybrid system with an advanced efficient fuel diverse steam engine would be even better.  Yes, oil prices are expected to continue rising and wood for fuel will become more attractive and important especially in places where wood is abundant and oil is scarce and expensive.  Wood pellets are probably the best choice for automotive fuel because pellets can be handled and controlled more easily.  You say that you cannot make wood pellets yourself.  The best present alternative might be to buy commercially produced pellets.  Pelletizing bio-mass, including wood, does not require high technology.  I suspect that small scale pelletizing equipment will become available in the near future if it is not already on the market. 

 We hope that this is helpful.
 Our best to you.
 John A. Cozby

Dear Jukka,                     Feb. 6, 2012
  
       When you sent me your last e-mail I was returning from a technical steam meet in Sacramento, State of California that was sponsored by the International Association for the Advancement of Steam Power and the Steam Automobile Club of America.  I had a good time, but I have had some catching-up to do since I got back home.
         About wood pellets for automotive use: A fluidized bed furnace is probably the best choice.  That was something that I learned at the “Steam Meet”.  I was aware of the fluidized bed, but I better understand it now, and its potential for automobiles. 
 
        On the subject of Finland’s topography: I realize that Finland is lower and smoother than Norway and Sweden.  The topography of Finland is more like that of the State of Louisiana – low, wet, and forests.  When I lived in Louisiana (South-eastern U.S.A.) we used wood for heating during the winter.  We used both fire-places and cast iron wood stoves.  When I lived in the State of New Mexico (South-western U.S.A.) we used wood for heat and cooking.  When I lived in the State of Idaho,(the northern part with mountains and forests – much like western Montana), we lived in an old house that had a wood burning furnace in the basement for central heating.  When we were working on the steam engine prototype program in Butte, Montana we used wood to heat the shop/fabrication area.  (Idaho and Montana are in North-western U.S.A.) Therefore I understand your situation very well.  I have a recent newspaper article that says: “The number of households using wood as their primary heating source nearly doubled in the State of Maine from 2000 to 2010, while growing by a third nationwide, according to U.S. Census figures.”  The article goes on to say that Montana is the third highest wood burning state in the nation (This is interesting because so much of  eastern Montana is almost treeless).
   
 Thank you for your thoughts and input.

John A. Cozby

Dear Jukka,                                                             January 16, 2013
     It was good to hear from you again.  I truly appreciate your interest in steam engines.  I would have gotten back to you sooner, but I was studying and reviewing the Besler Corporation’s Study, Steam Power System for Landing Craft for the Office of Naval Research, 1957.  It is very interesting.  I am planning to go to Sacramento, California for the Second Annual Steam Meet and Technical Conference, March 1 - 3.  The Besler Study was to give me more background for the Steam Meet and Technical Conference.
     On the matter of wood fueled steam power for automobiles: You are correct about the burning characteristics of wood.  You are right about hybrid being a solution.  I have always said that steam engines can be used in hybrid applications.  We are in agreement on that point.  You have discussed wood for automobile fuel before and that a great amount of wood is available in your country.  I will now go into more detail about using wood for fuel.  You are also right about “Controlling burning speed of gases is easy to do fast.”  I am not going to prove you “wrong”, but I will show that you are right on both issues.  I will also show that your being “right” is good.
     First we must realize that there are two very different ways of using wood for fuel.  If the wood is used in its raw, natural state as solid wood pieces cut from a tree, and the wood is the only fuel used then the hybrid approach is a good choice.  Let the wood generate electrical energy and the storage batteries/electric motor handle varying load requirements.  You have very good insight into this.
     There is another way to use wood as fuel.  In this second method we will call wood the primary fuel, but not the only fuel.  Wood is used for most of the heat energy needed.  This second method is meant for driving the vehicle directly by the steam engine.  This second method is much more involved and includes at least twelve different aspects:
     1.   The wood feed stock must first be pelletized (small pellets are best and grains can be used)
     2.   A small quantity of oil (either petroleum based or bio based) should be mixed into the pellets to improve their burning characteristics (wood chips can also be used)
     3.   A fluidized bed pellet furnace will give the best firing and stirring the pellets will help
     4.   A gas burner is used in conjunction with the wood pellets for fast start-up and to quickly raise temperature and pressure when higher load demands occur.  The gas can be compressed natural gas, compressed methane, or liquified petroleum gas – either propane or butane.  Propane or compressed natural gas is better in cold weather
     5.   Increasing combustion air flow velocity improves the firing rate and can be varied
     6.  Increasing furnace pressure improves the firing rate and can be varied (Pressure fired boilers are smaller.  The higher pressure and velocity are turned down when idling or at light loads)
     7.   Fuel pre-heating improves ignition and combustion
     8.   Combustion air pre-heating improves ignition and combustion
     9.   Blower air cut-off to the furnace can reduce heat to the boiler quickly
    10.   Using small amounts of pellets makes heat control easier and decreases residual heat problems
    11.   When a great amount of residual heat is too much for the boiler tubes the furnace gases will be ducted directly to the exhaust flue, by-passing the boiler
    12.   A multi-speed or variable speed transmission will help the boiler/furnace performance.

This approach is complex and will require a good amount of development, but should work very well.  It is basically a simple matter.

     Your question of weight, wood/h, and rpm for 20 kW:
20 kW is equal to 27 horsepower (hp).  I have done many calculations and estimates on the weights of three stage reheat engines in this general range in the past.  There is no simple answer because there are so many variables such as: What materials? What bore and stroke? What pressures and temperatures? What speed? What application? And so forth.  Designing for best efficiency at constant speed and load makes a less expensive, simpler, and lighter engine possible.  Not needing a transmission with a drive system also reduces weight and costs.  In The Steam Automobile Bulletin, November - December, 2012 pages 4 - 8 are devoted to the Jay Carter engine/system and technical specifications as follows: 90 hp at 5000 rpm and 2000 psi at 1100 ˚F; capable of operating at 1500 ˚F and 3000 psi and at 6000 rpm; 2.5 inch bore X 3 inch stroke.
   Engine 60 pounds
   Condenser 35 pounds
   Boiler 126 pounds and 80% efficiency
A small three stage reheat engine should weigh about the same as the Carter engine.  The condenser should be about the same.  The boiler/furnace should be less because the three stage engine is more efficient and the horsepower requirement is less.  The total package should run about 200 pounds.  I do not know what the generator will weigh, but this should give you some idea of the expected weight.
   As for the speed, the rpm is a function of the length of stroke and piston speed employed.  3600 rpm and above can be optimum.  A stroke of 2 inches to 3 inches is probably a good choice.  3 inch stroke at 2500 fpm gives 5000 rpm.  Probably would run at 80% of that speed, or 4000 rpm.
     How much wood/h?
The heat value of different woods varies.  Marks’ Engineers Handbook, 4th Ed. gives a table on page 802.  With a boiler efficiency of 80% and an efficient 3 stage reheat engine at 20 kW the wood need should be about 21 to 25 pounds per hour.  With a 90% boiler efficiency the requirement should be 19 to 22 pounds per hour.  An hundred pounds of wood should give up to 5 hours run time and at 60 mph a range of around 300 miles.  The figures would be about the same for a stationary electrical power generating unit of 20 kW.  Higher or lower power generating units would be proportional, that is, 10 kW would give 10 hours and 40 kW would give 2.5 hours.
Some stationary units could be co-gen, producing power and heat.  Some stationary units could have water cooled condensers.  An automobile with a 20 kW generator can provide both electrical power and heat to a home or business in emergency situations.  One of the advantages of a steam automobile in cold weather is that it can easily provide immediate economical heat for defrost and passenger comfort.
     The subject of condenser vacuum:
   Yes, you are right.  In many situations it will be difficult or impossible to maintain 1 to 2 psi pressure in the condenser.  Air temperature and engine load changes affect how low of a pressure can be achieved in the condenser.  Abner Doble pointed out that the condenser works better in cold weather than in hot weather – just a fact of life.  The best situation is one in which the weather is cool enough and the automobile is traveling at a speed high enough that the condenser fan is not needed and the vacuum is being maintained at 1 to 2 psi.  That would be ideal.  When the demand on the engine is greater or the weather is hotter the engine will still operate effectively, but at a slightly lower efficiency.  The condenser size and efficiency, and the cooling fan capacity greatly affects what pressure the vacuum can be.  For most automotive applications an extra large condenser would not be practical or desirable.