Andrew D. Todd

Mini-Blog #1

I do not propose to make this a public blog, and I am therefore not going to enable comments or use blog software. It will be primarily a place where I can conveniently respond at a length of two thousand words to magazine articles of ten thousand words.  I may possibly use it as a place to post book reviews.

Andrew D. Todd
1249 Pineview Dr., Apt 4
Morgantown, WV 26505

adtodd@mail.wvnet.edu

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Energy and Transportation
October 26, 2009

The following are a series of critiques of articles dealing with  energy and transportation. The people involved, both authors and the  businessmen they  report on, have their hearts in the  right place. But good intentions are no substitute  for knowing what  one is doing.


Tony Long, "Science:  Discoveries: Aug. 22, 1962: First Nuke-Powered Cargo Ship Docks" (Aug.22.2008)
 http://www.wired.com/science/discoveries/news/2008/08/dayintech_0822

This is a discussion of the nuclear cargo ship Savannah. Tony Long concludes that the Savannah was uneconomic-- which was true-- but proceeds to the faulty conclusion that a nuclear-powered cargo ship is impossible. The basic problem of the Savannah was that  it was much too small to have an efficient nuclear power installation. The one class of ships which were in the right power range (150,000 hp-200,000 hp), the  ocean liners, were being superseded by the airliner. At about the time the Savannah was built, the Navy had adopted a policy of using nuclear power in surface ships of at least 80,000 hp  (aircraft carriers and cruisers), and in submarines, of course; oil-powered  gas turbines in surface ships of  30,000 hp-80,000 hp (destroyers and frigates);  and diesels  in ships of  20,000 hp or less (typically fleet auxiliaries). The nuclear-powered merchant ship Savannah, with only 20,000 hp, was an extremely  marginal proposition, even by naval standards.

The Savannah was an artifact of economic protectionism, designed around the assumption that cheap labor goods might not be imported, and that the only things which it was permissible to import were things which could not be made in America and which did not compete with American products, eg. bananas from Central America, and certain classes of high-end manufactures from Western Europe, such as Rolls-Royce automobiles. A nuclear cargo ship big enough and fast enough to be efficient would have broken the  economic rules.

Now, however, merchant ships are getting bigger and faster than they  used to  be. A big and fast containership, on the order of a Nimitz-class aircraft carrier (80,000-100,000 tons, 300,000 hp, 35 knots), operating between China and North America, might very well employ nuclear power. Given its emphasis on speed, it would probably dock at Prince Rupert in northern British  Columbia, so as to move cargo by rail as much as possible. The Canadian railroads running  to Minneapolis, Chicago, Detroit, and New England could be electrified, of course. 


Daniel Roth, "Driven: Shai Agassi's Audacious Plan to Put Electric Cars on the Road," WIRED MAGAZINE: 16.09
 http://www.wired.com/cars/futuretransport/magazine/16-09/ff_agassi?currentPage=all

See also: Chuck Squatriglia, "Better Place Unveils an Electric Car Battery Swap Station"
http://www.wired.com/autopia/2009/05/better-place/

Roth's article  is largely a profile of Shai Agassi, a software executive who wants to build a system of electric automobiles along lines derived from the consumer electronics industry. Agassi's primary test market is the state of Israel, a kind of de-facto island, where it is only possible to drive limited distances in any direction. His alternative test market  is Hawaii, or, more specifically,  the city of Honolulu on the island of Oahu. His emphasis is on using computer systems to efficiently allocate electric automobiles needing  recharging to parking spaces fitted with rechargers, and, more recently,  to available interchangeable battery packs in service stations. Shai Agassi is not an arrogant twit like Elon Musk (*), but he suffers from a tendency to force the lessons of his previous experience into places where they are not  applicable. Daniel  Roth, acting as a kind of cheerleader, does not raise the kinds of questions which need to  be raised.

Back during the 1970's oil crisis, there were a whole series of land transportation projects funded by the  United States government.  An inordinate number of these projects were contracted out to aerospace companies with no knowledge of land transportation.  These companies were in a depressed state as a result of  the spending  drawdown at the end  of the Vietnam War. There was an element of corporate welfare. More seriously, the aerospace people tended to become enraptured with the idea of their own technological superiority, and to proceed in deep ignorance of the proven practices of  railroading, etc. This meant that they were always doing things the hard way, admittedly with great technical virtuosity, but with  very little in the way of practical results.

Something similar seems to be happening now. There are a  lot of people who have been pushed out of the stagnating computer industry, and who are inclined to use computers in all the wrong ways. In particular, Shai Agassi seems to be attempting to force the false  analogy of the cellphone onto the  electric automobile.

1. The most basic truth about automobile transportation is that different people do not drive the same distance. A minority of people drive much longer distances, and  use up most of the energy involved in automotive transportation. Archetypally, this means someone with a highly skilled job who drives fifty miles to work, and fifty miles  home again, for a total of several hundred miles a week. The nature of his skills means that he cannot just find a job down the street. Someone who merely drives for his own convenience-- a retiree, for example-- will drive a distance which shades over into walking distance, say thirty  miles a week.  Stores, restaurants, etc. locate themselves for the convenience of their customers, not the other  way around. The latter kind of driver does not need special infrastructure to use an electric car. He can have a charger in his garage, and  get a week's supply of electricity in a single night. But in any case, such a driver would only need a gallon of gasoline a week, or possibly even as little as a gallon a month. That  is  not enough to create a problem, so there is no  compelling reason for such a driver to get an electric car. What  this all means is that the electric car  developer has to solve the problems of the long-distance commuter, or he is just wasting  his time.

2. Electric automobiles are not cellphones. You cannot put  an electric automobile in  your pocket and carry it on an airliner. Worldwide standardization is meaningless. Transportation is dependent on geography. A transportation system appropriate for Israel will almost certainly be wrong for Montana.  For what it is worth, the  world has gotten along quite well with different countries either driving on the right side of the road, or  driving on the  left side  of the  road. The kind of people who go back and forth between different countries sufficiently often that they  are likely to become confused are precisely those who can afford to hire drivers anyway.

3. Assuming an automobile has regenerative braking, it does not need much power to  travel  at low speeds.

4. The time constraint means that an automobile cannot go very far at slow speeds.

5. At least in urban areas, it is not safe to drive at high speeds on roads which are not expressly  designed for such a purpose,  such as Interstate Highways, or as  the Europeans call them, motorways.

6. As a consequence of Items 3-5, the transportation energy problem is primarily a problem of high-speed roads, not of side streets and parking places.

7. Experience with previous land transportation systems, such as railroads and stagecoaches, has been that if you need to change out your power system on a regular basis, the best thing is for both the power system and the payload container to have their own wheels, and  to have the  two connected together by a quick-release coupling, which can be unfastened in a minute or less. In  the steam engine era, it was normal for a high-speed express train to change locomotives every hundred miles, or about every hour-and-a-half. For stagecoaches, the norm had been about ten miles between changes of horses, so that a stagecoach might need a herd of a hundred horses to keep it rolling along continuously. An electric automobile can be given a trailer filled  with batteries, with an electric connector built into the  hitch, and there can be two or three trailers for  every automobile, if that is what is required. For  that matter, one can have a trailer with a gasoline engine and gas tank, if the situation calls for it, or a trailer mounting any other specialized apparatus one might  happen to need, such as a trolley pole. On this basis, one does not worry about whether a power system is truly exhausted or not, or whether  it could be replenished in time to go on-- one simply makes an exchange as an ordinary matter  of routine, and makes such credits after the fact as may be appropriate.

8. As a consequence of items 6 and 7, an electric car can have its own internal  battery, in  the golf cart class, good for, say twenty  miles at twenty miles per hour, something easily within current capabilities. The car's origin and destination are a reasonable distance from high-speed routes, let  us say, not more than five miles (at most), and probably more like one mile,  on average. When the car gets on a high-speed route, it replenishes its internal battery from the power systems provided for the high-speed route. One does not need a lot of recharging stations-- instead, what one needs is the means to attach or activate a power supply in some fashion to  large numbers of vehicles as they go up the freeway  on-ramp. There are, of course, a number of different ways to do this.

a. One can use battery-trailers and stop to change them every  half-hour or so, at something like an American truck stop; b.  one can fit the automobile with an extensible trolley  (or the equivalent) to draw power from  overhead wires; or, c.  one can drive the automobile onto a transporter vehicle which stays on the  highway, and carries automobiles from one exit or interchange to another. This system has the advantage of being compatible with existing gasoline-powered automobiles.
There are a lot of minor variations within these three general options. However, what is necessary is to arrive at a plan for rebuilding the freeway, a piece of government property.

9. In terms  of pure  geography, Israel  is something like one of the world's  ideal  locations for electric railroads. However,  one gathers that railroads were systematically neglected for the first  fifty years of Israel's existence, and Israel is only now beginning to make up for lost time. Railroads can and do carry  automobiles in transporter cars, when that is desired.

http://en.wikipedia.org/wiki/Israel_Railways

However, for a  large office building, or a shopping mall, or a college campus, or a sports stadium, it is effectively impossible to give everyone a good parking  place. Automobiles take  up too much space, and someone or other will have to walk  half a mile to  his car. On the other hand, it  is possible to build a good train station into such a building, and with intelligent organization, the train can carry people to and from parking  lots anything up to fifty miles away, only a short drive from their respective homes.

10. A certain type of Silicon Valley refugee knows how to sell upscale consumer goods, but  does not know how to sell public goods, and this tends to  distort his thinking. In terms of public goods, it  is not possible to  do much of anything as long as the organizer is  thinking about becoming personally wealthy, taking  Bill Gates  (old version) as a role-model. To successfully build large systems involving public property, there  has to be someone more or less like  Robert Moses.
http://en.wikipedia.org/wiki/Robert_Moses

Moses had inherited money, his father having  retired from business when he was nine years old, and had been educated as a professor before going into public administration.  He could get away with doing things only because it could be taken for granted that  he was not  trying to enrich himself at  public expense. Interestingly, the architect of parkways never learned to drive-- that was something that  chauffeurs did. It really does matter that Shai Agassi sounds as if he might be a man on the  make.

(*) For Elon Musk's defenders, the word he used in reference to Randall Stross, which I cannot quite bring myself to repeat, is indubitable evidence of  arrogant twithoot.

Jonathan Rauch, "Electro-Shock Therapy," _The Atlantic Monthly_, August, 2008
http://www.theatlantic.com/doc/200807/general-motors

This is a portrait of the General Motors Volt project. In many respects, it resembles Michael Shnayerson's _The  Car That  Could: The Inside Story of GM's Revolutionary Electric Vehicle_ (1996) about the EV1 project. For practical purposes, Volt  seems to be a continuation of EV1, only with somewhat different design objectives. That is, it is apparently less of a sports car, and more of a family car,  but  the design emphasis is still on achieving  low drag and the  lightest possible weight exclusive of the battery, drawing heavily  on aerospace design practices to achieve these goals.

Jonathan Rauch fails to address the real reasons which underly  General Motors' successive failures to develop an electric car. GM's essential  problem is that the company is organized around gasoline, and  would not have any reason to exist in  the absence of gasoline. GM owns no roads (outside of the proving ground),  nor does it take any responsibility for  roads. On the contrary, GM's most lucrative product until recently, the SUV, has been based around the  tacit claim that roads do not exist.

The special genius of gasoline lies in storage. Gasoline or diesel oil is about the most lightweight, compact, and convenient  non-nuclear means of storing energy there is.  Electric batteries are grossly inferior at  storing energy.  GM's successive attempts at electric car  designs have been failures precisely because  they  have been attempting to force electricity into the  likeness of gasoline. The illusion is brittle. For example, the first Toyota Prius was unsatisfactory because it was slightly underpowered. Japanese engineers could not quite believe how hard and fast Americans drive, and they reduced the power accordingly. This  was not a fundamental  problem, however. It just meant that the  engine  had to be souped  up a bit, and the car would get slightly worse gas  mileage. It is no big deal to add an extra gallon or two to the gas tank. Electric cars, on  the other  hand, tend to  be pushing the limits of their battery technology, and that sort of miscalculation is likely to be  serious. A plug-in hybrid, consistently operated beyond the limits of its battery, might  well get  worse gas  mileage than a standard  hybrid,  because it would have to haul all those batteries around.

The genius of electricity, in distinction to that of gasoline, lies in flow. Successful electric transportation means building an electricity supply into the road, usually via an overhead wire. Far and away the most effective system of electric transportation  is the electric railroad, the most perfect kind of road. There are all kinds of different variations of electric railroads, such as subways, streetcars, trolley-buses,  and people-movers. Lastly,  there is Personal Rapid Transit, where each train is scaled down to the size of a  single automobile to provide the maximum in flexible routing. When passengers want to take automobiles with them, the railroads provide Auto-Trains, driving each automobile onto a transporter car and parking it. Advanced transportation planners thirty and forty years ago drew up schemes in which PRT vehicles could be made to carry single automobiles. It was the standard "redesign with automation" treatment--  give everything a computer, and design for maximum possible versatility. The problem for  GM is that the enlightened railroader arranges to carry an automobile by treating it as a glorified suitcase  with wheels. Any old automobile will do to drive onto  the railroad transporter  car and park there. In fact, a smaller automobile usually has an easier job of finding a parking place, so the ideal vehicle for "piggybacking" on railroads might well be something like an  enclosed golf cart.

Silicon Valley companies are not especially well-managed. They make as many  mistakes as everyone else.  This  includes Apple and Steve Jobs. Silicon Valley's mistakes are  bailed out by Moore's  Law, by the fact that making an integrated circuit  smaller also  makes it  faster and cheaper at the same time. When one of Steve Jobs' gadgets misses its market, as  they  sometimes do, he has only to wait a year, and then see if there is a market at half the  price, or twice the power. Apple does not even make any of the critical parts of a computer, such as chips and  disk drives, but uses commercially available off-the-shelf components. Apple really does not do much more manufacturing than home hobbyists do. In automotive terms, Apple might be compared  to one of those  importers who, back in the 1950's, brought in various odd European cars, operating at a level one step above used-car dealers, yet introducing  Americans to the radical idea that an automobile did not have to have nonfunctional tail fins. Apple makes its money by teaching people about the exciting new things one can do with microelectronics. The strategy of miniaturization is not applicable to batteries, because batteries are supposed to produce power rather than information. It is a sign of GM's moral desperation that it is looking to Apple for guidance about how to run a manufacturing company.

---------------------------------------
Ref:
http://en.wikipedia.org/wiki/Toyota_Prius


The Tesla

The Tesla Model S is fitted with a lithium-ion battery pack weighing somewhere in the neighborhood of a thousand pounds, and delivering  70 Kw-H, for a claimed range of 160 miles. These figures are broadly compatible with GM's figures for the EV1 with lead-acid batteries of about the same weight (70 miles city, 90 miles highway). That is, the EV1's drag coefficient is about twice as good as that of the Tesla, but the Tesla's lithium  batteries are four times better-- provided they don't burst into flames.

It is claimed that an extended range version will be available, capable of 300  miles. Batteries are compact, and the  major  cause of automobile energy consumption at speed is  aerodynamic drag, not rolling resistance. Because the batteries are compact, they can be stored in such a way as not to require an appreciably bigger body. The implication is that if Tesla lengthens the frame a couple of feet, between the  driver compartment and the front and rear wheels  and sticks in another thousand pounds of batteries, that would  get them a car weighing about five thousand pounds, but with very nearly the same power requirements as the standard model. 

The EPA highway driving cycle assumes substantial adherence to the 55 MPH speed limit. If one actually drives at 70 MPH, in a state  where this is legal, one has to expect that the  gas mileage (assuming an  electric drive, as distinct from a conventional gearbox) would be only about  65% of that for 55 MPH. To drive long distances, with a practical economy of time, one has to drive fast. Thus the Tesla's actual range  would  be a hundred or two hundred miles, according to model. Another point is that battery performance is sensitive to temperature.  What is possible in California is not necessarily possible  in the Midwest, especially in the depths of winter.

The Tesla has a very high claimed horsepower (I believe about  400 hp), though this is matter of nomenclature. Unlike a gasoline engine, or a mechanical gearbox, the limiting factor of electric motors is generally  overheating. As Charles Kettering noted in designing the first  electric starter, one can run a motor at very high power  level for a  burst, provided one does not continue. In the case of accelerating an automobile, the greater the  power, the greater the acceleration, and  the less time before the automobile reaches its designated speed. Since this speed is  restricted by law, the total amount of energy required and consequently, the total surge of heat resulting from acceleration is also limited.

Summing up, the performance of the Tesla is likely to  be marginal. It will depend on the user being willing to carefully plan out his fuel supply, the way airplane pilots do. The car will not respond well to unforeseen events which require transportation. Barring  its price, the Tesla would be a perfectly adequate car for eighty  percent of the population, but-- this eighty percent of the population only uses twenty percent of the gasoline, and is perfectly happy with used cars. The twenty percent of the population which drives long distances,  uses most of the gasoline, and which is disposed to pay substantially more than $20,000 for a new automobile, would not find the Tesla so satisfactory.

http://www.rsportscars.com/tesla/2013-tesla-model-s/