Monday, 8 November 2004

CAN WE BUILD MORE EFFICIENT ENGINES?

Stop global warming


Yes, I think we can. The present internal combustion engine was mostly developed in a time when fuel cost and efficiency were not imperatives. We need to go back to the early days of engine devleopment and reassess the way designers handled branches in the design road. We may have overlooked some better choices way back when the discovery of oil in Oklahoma and Texas seemed to say that there would be cheap gasoline forever.

One of these early branches in the road was a choice between four-stroke cycle engines and two-stroke cycle engines for automobiles. At the time, we used carburetors to feed fuel to the cylinders. In this context, the four-stroke engine is a far better choice. (More efficient and less polluting.)

But, the trend today is toward injection of fuel directly into the cylinders. With this modern option, the two-stroke cycle actually provides a far more efficient engine. Here are some other choices that need to be reviewed:

1. Engines are only designed for either gasoline or diesel, and nothing else.
2. Compression ratios are lower than one would choose for best efficiency.
3. Engine design principles are not based on a need to reduce weight.

Some people are looking at the exciting possibilities still left to be explored. A possible outcome may be radically new engine types in the near future.

Ernie Rogers

Saturday, 11 September 2004

MPG Update

I changed fuel in the last few weeks. Currently, I am using Philips diesel from the North Salt Lake Refinery, used in this intermountain region. I seem to have better mileage with this fuel, now getting 62 mpg.



This is a point for reflection-- what further change in driving or car properties should I make to increase my mileage a little more? Any suggestions?



Ernie Rogers

Sunday, 22 August 2004

Ernie's Alaskan Adventure

This summer, my grandson, Kai Rogers, and I drove to Alaska--Salt Lake City to Anchorage, 3,000 miles. Of course, we went in the thrifty, fuel-sipping Beetle TDI diesel.



Total fuel for the trip to Alaska, 3,000 miles, was 52 gallons. Not bad --- about 57 miles per gallon. On the return trip we did a little better, getting 58 miles per gallon.



I had hoped to do better. Here in the western states, my summer mileage is consistently about 60 miles per gallon. We surmise that the reason is the difference in climate. It would be necessary to use a little different diesel fuel blend in northern Canada and Alaska to insure that the fuel doesn't solidify if the weather were to suddenly turn cold. Cold-weather fuel contains a little less energy than what we use down around Utah in the summer time.



You can follow the link to my car's web page to see some pictures and hear more about the trip.



Ernie

Monday, 24 May 2004

World is running out of oil--then what?

I think it is no secret now, when I tell you that the world is running out of oil. (See Hubbert's peak.) Up until now, most of our oil has been used to make energy (or as fuels). This has got to stop because the day is coming when oil will be more valuable than energy, and will be needed for other uses. (Should I mention global warming?) That brings up a new and timely idea.



If we think of using oil to make energy as a reaction:



Oil --> energy.



We should remind ourselves that the reaction is reversible, at least in principle:



Energy --> oil



There is an inefficiency involved in going either way. The existence of this reversible reaction has the effect of placing a link between the cost of energy and the cost of oil. Some examples:



1) The cost of oil can not be substantially lower than the cost of equivalent energy from other sources (allowing for inefficiency), otherwise energy production will shift to use of more oil. (Which just supposes that economics has more sway than common sense.)



2) The cost of oil can not be substantially higher than the cost of equivalent energy from other sources (allowing for inefficiency), in the long run, because man's inventiveness will allow oil to be made from energy.



The question then follows as to whether there are or can be practical means for making oil from energy.



We may say that we live in an exciting time, when the world has to face a transition from the "industrial age" when we have powered everything with fossil fuels. The daily advance of news on this, this summer, is quite surprising. The underlying question is, what will replace oil? Wind turbines, etc., make electricity, not oil. The question hasn't been very important until now, when we can see that we really are going to run out. There are maybe three answers to the question--



1) Biomass to oil, fuel, etc. An example is NREL's research on using the Fischer-Tropsch (or F-T) process to convert trash to oil--not the best approach. The direct conversion with pressure and heat is better (sorry, don't have the reference, now in pilot plant operation). There are many others, including my favorites: growing biomass at sea for conversion to methane, and producing "biodiesel" from low-value crop materials.



2) The darling of industry, converting coal (or natural gas, oil shale, etc.) to liquid fuels. This is already in use in one two-step process: "coal gasification" to synthesis gas, then coversion to long-chain hydrocarbons with the F-T process. This produces a very good-quality diesel fuel, or about anything else you want. Pretty rough on the environment, so only half a solution.



3) Efficient conversion of electricity or other high-quality energy directly to hydrocarbons. Most of the good alternate energy approaches produce electricity. Okay, I will list the best of these: wind, tide /wave, PV, and solar-thermal. A unique exception, a dish solar concentrator, can also produce high-quality heat (10,000 suns) at the focus.



Number three is exactly what I was talking about. It is the only one that makes sense but doesn't rely on photosynthesis. Notice that I have excluded hydrogen from consideration, as a replacement for oil and other liquid fuels. I know further that hydrogen can be made from electricity, and in turn can be used to make hydrocarbons, by the F-T process. This looks way too expensive and inefficient to get very far, in my judgement.



I was searching around on the internet last night, looking for new ideas on making synthetic oil or hydrocarbons--Ideas that would fall within #3. I found nothing! This topic, producing hydrocarbons from electricity or heat directly, is of great importance for the future of man. Though it may be a little early yet, this will be a major problem soon. When we (the world) turn our attention to it, solutions will quickly emerge. I see two paths:



1) Use of heat. Two reactions at high temperature have been mentioned in the past:



H2O --> HO + H --> H2 + O2

CO2 --> CO + O --> CO + O2



Removing the oxygen, the products together are "synthesis gas," which can be used to make alcohols or long-chain hydrocarbons by the F-T process. Or, either of the gases singly, with water or CO2, can be used to the same end.



There are surely many other known processes that I am unaware of.



2) Use of electricity to make hydrocarbons directly. This seems to be a largely unexplored field, having been at an economic disadvantage for the last century. Here, two approaches come to mind: plasma chemistry, driven by electrical power. A subset of this are the thermal processes mentioned in 1).



A second approach is well known, but not worked on currently, I think-- that is organic electrochemistry for making fuels. In principle, electrochemical reactions carried out in cells can make hydrocarbons and other organic materials. A few industrial processes already exist that do this sort of thing.



Michael Faraday reported an experiment that should be a point of beginning for research. He passed an electric current through a solution containing carbonate ion, and discovered that organic compounds were formed. (Formic acid or formaldehyde?)



I hope I have shed some warm light on Hubbert's peak.



Ernie Rogers

Thursday, 20 May 2004

Facts on global warming

Global warming has so many implications for industries and government, besides being an environmental issue, that there are powerful forces on all sides trying to convince us of one reality or another. You can only know the truth by digging it up for yourself. Here are some helps in that direction.



1. I just finished reading "The discovery of Global Warming" by Spencer Weart. (Harvard Univ. Press, 2003) This is an account of the history of the subject, written from an expert viewpoint, but fairly balanced. Weart is the director of the Center for History of Physics at the American Institute of Physics--great credentials. This is a great book, but won't tell you details of the science, just how various evidence has fit together over time. It's quite an eye-opener. Only a year old, it is already out of date on technical grounds. You can probably check out this book in a college library, I did.



2. A big sticking point among some "professionals" has been the publications of John Christy (U. of Alabama, Huntsville) which have shown no warming trends in satellite measurements of atmospheric temperature. His measurements have been a great comfort to the present Republican administration, which abandoned the Kyoto agreements that the U.S. had helped to forge. Christy's work is now being seriously challenged by two recent publications that show large warming trends based on satellite data. (If interested, I think you can get a recent Christy paper on-line: John R. Christy et al. "Update on Microwave-based Atmospheric Temperatures from UAH" 15th Symposium on Global Change and Climate Variations. 2003) Christy has a web site: john.christy@nsstc.uah.edu. Following are the challenging references.



3. Qiang Fu et el., "Contribution of Stratospheric Cooling to Satellite-inferred Tropospheric Temperature Trends" Nature 429, 55-58 (6 May 2004). Fu says that Christy overlooked the influence of tropospheric cooling in his calculations. He makes the correction, and finds a large warming trend. This appears to be a hot topic right now. Hard copies of this issue may not have reached library shelves yet, but a helpful librarian can download the paper for you.



4. Menglin Jin, "Analysis of Land Skin Temperature Using AVHRR Observations" Bul. of the American Meteorological Soc. (BAMS) April, 2004, p. 587-600. Jin analyzes satellite data to obtain earth surface temperature. He also shows a large warming trend. This is a major paper, lots of references. Most of the figures are in color, good luck getting it copied.



Final word: It can be shown logically that a warming earth does not necessary cause the upper troposphere to get warmer, as Christy would argue. I will provide this in a future post.



Ernie Rogers

Mad about fuel cost? -- Save 10% right now

Are you mad about the present cost of fuel? You can save about 10% or more on fuel cost right now, and help to stop global warming at the same time.



I am working on ways to reduce fuel consumption in transportation, such as reducing aerodynamic drag. So, I experiment with my car-- I measure my fuel economy all the time. Here are some facts about highway driving:



* Reducing highway speed from 70 mph to 65 mph saves about 8% of fuel.

* Reducting speed from 75 mph to 70 mph saves about 10% on fuel.

* At 80 mph, you are throwing fuel away. If you drive over 80 mph and push the pedal any time you feel the need, then you have the potential to save as much as 30% of fuel usage.



Hey, if you are seriously angry about the price of fuel, you can bring it down, if you can just relax a little when you drive. Give it a try. Let me know your results.



Good luck