Germany’s green transition is a disaster. Twenty years ago, Germany had 23 nuclear power plants that generated 30% of the country’s electricity cleanly, cheaply, and reliably. These plants have all been shut by the government as part of a commitment to clean energy. What could be cleaner? Germany has switched to a mix of wind and solar, plus a significant shift to coal power. Wind and solar use a lot of land compared to nuclear, and they break down leaving fields of debris. There is now a lack of electricity to power homes and industries, and what power there is, is unreliable, due to the many dark windless days in Germany.
The lack of reliable electricity is crippling German industry now that Russian gas has been cut off. In this environment, why would the Germans order special trains and boats that burn, hydrogen that’s made from electricity and natural gas? My understanding of the reason is that, Germany sometimes has too much wind power and nothing to do with it. They plan to store this excess by making hydrogen that they can use to power their trains and boats. The cost is high, and the efficiency is poor, but the electricity is free.
Hydrogen is not as compact a fuel as gasoline, nor is it as cheap as electricity, but it’s cleaner than gas, and in some ways it’s better than battery-stored electricity. While hydrogen takes a lot of storage space relative to gasoline, high pressure helps, and the storage is cheaper than with batteries. Also, hydrogen fuel is transferred faster than electric fuels. Trains and ships are chosen for hydrogen because they are good at carrying bulky items. The transition to hydrogen is relatively straightforward with trains, since many are already powered by electricity. Hydrogen fuel cells can make the electricity on board (in theory), while avoiding the need for expensive overhead wires. The idea sort-of makes sense.
Germany’s first hydrogen train. cancelled after 1 year of poor operating.
The first German train to use hydrogen powered them with fuel cells that generated electricity. It began service in October 2022, but the fuel cells proved unreliable. Service ended one year later, October 2023, replaced by polluting diesel (see here). The Hannover line plans to replace these with battery-powered trains over the next few years. There are also plans for a hydrogen-powered ferry, but it is not clear why the ferry should prove more reliable than the train, or cheaper.
San Francisco’s hydrogen-powered ferry, $30 million, 15 knots top speed, 75 passengers, no cars. Long delayed.
In the US, the Biden administration has paid, so far, $30 million for a hydrogen ferry in San Francisco. It’s two years behind schedule and over cost, taking only 75 passengers and no cars at 15 knots, 17mph. In the US, and likely in Germany, most of the hydrogen will be made from natural gas. A better solution, I think would be to power the ferris and trains by natural gas and to store the excess electricity in land-based batteries or as land-based hydrogen for land-based fuel cells.
Germany is committed to electric trains, though, and hydrogen provides a route to power these trains with excess electricity. German customers take the train, in part, because they like them, and in part because German politicians have banned short-hop planes on competing routes, and subsidized electric trains. Yet another option to balance times of excess solar and wind power would be to subsidize electric cars, or at least allow theirs owners to trade electricity: to buy electricity when it’s cheap and resell it to the grid when demand and prices are high.
Per pound mile of material, the transport cost by ship is 1/4 as much as by train, and about 1/8 as much as by truck. Ships are slower, it is true, but they can go where trucks and trains can not. They cross rivers and lakes at ease and can haul weighty freight with ease. I think America could use many more ferries, particularly drive-on, fast ferries. I don’t think we need new fast rail lines, because air travel will always be faster and cheaper. The Biden administration thinks otherwise, and spends accordingly.
Amtrak gets $30 Billion for train infrastructure this year, basically nothing for ferries.
The Biden administration’s infrastructure bill, $1.2 Trillion dollars total, provides $30 Billion this year for new train lines, but includes less than 1% as much for ferries, $220 million, plus $1B for air travel. I think it’s a scandal. The new, fast train lines are shown on the map, above. Among them is a speed upgrade to the “Empire Builder” train running between Chicago and Seattle by way of Milwaukee. I don’t think this will pay off — the few people who take this train, takes it for the scenery, I think, and for the experience, not to get somewhere fast.
There is money for a new line between Cleveland and Detroit, and for completion of the long-delayed, and cost-over-run prone line between LA and San Francisco. Assuming these are built, I expect even lower ridership since the scenery isn’t that great. Even assuming no delays (and there are always delays), 110 mph is vastly slower than flying, and typically more expensive and inconvenient. Driving is yet slower, but when you drive, you arrive with your car. With a train or plane, you need car rental, typically.
New Acela train, 150 mph max. 1/4 as fast as flying at the same price.
Drive-on ferries provide a unique advantage in that you get there with your car, often much faster than you would with by driving or by train. Consider Muskegon to Milwaukee (across the lake), or Muskegon to Chicago to Milwaukee, (along the lake). Cleveland to Canada, or Detroit to Cleveland. No land would have to be purchased and no new track would have to be laid and maintained. You’d arrive, rested and fed (they typically sell food on a ferry), with your car.
There’s a wonderful song, “City of New Orleans”, sung here by Arlo Guthrie describing a ride on the historic train of that name on a trip from Chicago to New Orleans, 934 miles in about one day. Including stops but not including delays, the average speed is 48 mph, and there are always delays. On board are, according to the song, “15 restless riders, 3 conductors, and 25 sacks of mail.” The ticket price currently is $200, one way, or about as much as a plane ticket. The line loses money. I’ve argued, here, for more mail use to hep make this profitable, but the trip isn’t that attractive as a way to get somewhere, it’s more of a land-cruise. The line is scheduled for an upgrade this year, but even if upgraded to 100 mph (14 hours to New Orleans including stops?) it’s still going to be far slower than air travel, and likely more expensive, and you still have to park your car before you get on, and then rent another when you get off. And will riders like it more? I doubt it, and doubt the speed upgrade will be to 100 mph.
Lake Express, 30 mph across Lake Michigan
Ferry travel tends to cost less than train or plane travel because water traffic is high volume per trip with few conductors per passenger. At present, there are only two ferryboats traveling across Lake Michigan, between Michigan and Wisconsin, Milwaulkee to Muskegon. They are privately owned, and presumably make money. The faster is the Lake Express, 30 mph. It crosses the lake in 2.5 hours. Passenger tickets cost $52 one way, or $118 for passenger and car. That’s less than the price of an Amtrak ticket or a flight. I think a third boat would make sense and that more lines would be welcome too. Perhaps Grand Haven to Racine or Chicago.
Route of the Lake Express. I’d like to see more like this; St. Joseph to Milwaukee say, and along Lake Erie.
Currently, there are no ferries across Lake Erie. Nor are there any along Lake Erie, or even across Lake St. Clair, or along the Detroit River, Detroit to Toledo or Toledo to Cleveland. These lines would need dock facilities, but they would have ridership, I think. New York’s Staten Island ferry has good ridership, 35,000 riders on a typical day, plus cars and trucks. In charge are roughly 120 engineers, captains and mates, one employee for every 300 passengers or so. By comparison, Amtrak runs 300 trains that carry a total of87,000 passengers on an average day, mostly on the east coast. These 300 trains are run by 17,100 employees as of fiscal year 2021, one employee for every 4 passengers. Even at the slow speeds of our trains the cost is far higher per passenger and per passenger mile.
The Staten Island ferry is slow, 18.5 mph, but folks don’t seem to mind. The trip takes 20 minutes, about half as long as most people’s trips on Amtrak. There are also private ferry lines in NY, many of these on longer trips. People would take ferries for day-long trips along our rivers, I think. Fast ferries would be nice, 40 mph or more, but I think even slow ferries would have ridership and would make money. A sea cruise is better than a land cruise, especially if you can have a cabin. On the coal-steam powered, Badger, you can rent a state-room to spend the night in comfort. Truckers seem to like that they cover ground during their mandatory rest hours. The advantage is maximized, I think, for ferry trips that take 12 hours or so, 250 to 350 miles. That’s Pittsburgh to Cincinnatti or Chicago to Memphis.
New York’s Staten Island ferry leaves every 15 minutes during rush hour. Three different sizes of boat are used. The largest carry over 5000 passengers and 100 cars and trucks at a crossing.
A low risk way to promote ferry traffic between the US and Canada would be to negotiate bilateral exemption to The Jones Act and its Canadian equivalent. Currently, we allow only US ships with US crews for US travel within the US.* Cabotage it’s called, and it applies to planes as well, with exemptions. Canada has similar laws and exemptions. A sensible agreement would allow in-country and cross-country travel on both Canadian and US ships, with Canadian and/or US crew. In one stoke, ridership would double, and many lines would be profitable.
Politicians of a certain stripe support trains because they look futuristic and allow money to go to friends. Europeans brag of their fast trains, but they all lose money, and Europe had to ban many short hop flights to help their trains compete. Without this, Europeans would fly. There is room to help a friend with a new ferry, but not as much as when you buy land and lay track. We could try to lead in fancy ferries going 40 mph or faster, providing good docks, and some insurance. Investors would take little risk since a ferry route can be moved**. Don’t try that with a train.
In Detroit we have a close up of train mismanagement involving the “People Mover.” It has no ridership to speak of. Our politicians then added “The Q line” to connect to it. People avoid both lines. I think people would use a ferry along the Detroit river, though, St. Claire to Wyandotte, Detroit, Toledo — and to Cleveland or Buffalo. Our lakes and rivers are near-empty superhighways. Let’s use them.
Robert Buxbaum, January 2, 2024. *The US air cabotage act (49 U.S.C. 41703) prohibits the transportation of persons, property, or mail for compensation or hire between points of the U.S. in a foreign civil aircraft. We’ve managed exemptions, though, e.g. for US air traffic with Airbus and Embraer planes. We can do the same with ferries.
** I notice that it was New York’s ferries, and their captains, that rescued the people on Sullenberger’s plane when it went down in the Hudson River — added Jan. 6.
It’s good to have hero, someone whose approach to life, family and business you admire that you might reasonably be able to follow. As an engineer, inventor, I came to regard Peter Cooper of New York as a hero. He made his own business and was a success, in business and with his family without being crooked. This is something that is not as common as you might think. When I was in 4th grade, we got weekly assignments to read a biography and write about it. I tended to read about scientists and inventors then and after. I quickly discovered that successful inventors tended to die broke, estranged from their family and friends. Edison, Tesla, Salk, Goodyear, and Ford are examples. Tesla didn’t marry. Henry Ford’s children were messed up. Salk had a miserable marriage. Almost everyone working on the Atom Bomb had issues with the government. Most didn’t benefit financially. They died hated by the press as mass-murderers, and pursued by the FBI as potential spies. It was a sad pattern for someone who hoped to be an inventor -engineer.
The one major exception I found was Peter Cooper, an inventor, industrialist, and New York politician who was honest, and who died wealthy and liked with a good family. One result of reading about him was to conclude that some engineering areas are better than others; generally making weapons is not a path to personal success.
Tom Thumb, the blower at right is the secret to its light weight per power.
Peter Cooper was different, both in operation and outcome. Though he made some weapons (gun barrels) and inverted a remote control torpedo, these were not weapons of mass killing. Besides he but thee for “the good side” of the Civil War. And, when Cooper made an invention or a product, he made sure to have the capital available to make a profit on it too. He worked hard to make sure his products were monopolies, using a combination of patents and publicity to secure their position.
Brand management helps.
Cooper was a strong family man who made sure to own his own business, and made sure to control the sources of key materials too. He liked to invest in other businesses, but only as the controlling share-holder, or as a bond holder, believing that minor share-holders tend to be cheated. He was pro monopoly, pro trusts, and a big proponet of detailed contracts, so everyone knew where they stood. A famous invention of Cooper’s was Jello, a flavored, light version of his hide-glue, see the patent here. Besides patenting it, he sold the product with his brand, thus helping to maintain the monopoly.
Cooper was generous with donations to the poor, but not to everyone, and not with loans. And he would not sign anyone’s note as a guarantor. Borrowers tended to renege, he found, and they resent you besides. You lose your money, and lost them as a friend. He founded two free colleges, Cooper Union, and the Cooper-Limestone Institute, plus an inventor’s institute. (I got my education, free from Cooper Union.) Cooper ran these institutions in his lifetime, not waiting till he was dead to part with his money. Many do this in the vain hope that others will run the institution as they would.
Peter Cooper always sought a monopoly, or a near monopoly, patenting his own inventions, or buying the rights to others’ patents to help make it so. He believed that monopolies were good, saying they were the only sort of business that made money while allowing him to treat his workers well. If an invention would not result in a monopoly, Peter Cooper gave the rights away.
The list of inventions he didn’t patent include the instruments to test the quality of glue and steel (quality control is important), and a tide-powered ferry in New York. Perhaps his most famous unpainted invention was a lightweight, high power steam locomotive, “The Tom Thumb”, made in 1840. Innovations included beveled wheels to center the carriage on its rails, and a blower on the boiler fire, see photo above. The blower meant he could generate high-power in a small space at light weight. These are significant innovations, but Cooper did not foresee having a monopoly, so he didn’t pursue these ideas. Instead, he focussed on making rails and wire rope; he patented the process to roll steel, and the process for making coke from coal. Also on his glue/jello business. Since he made these items from dead cows and horses, he found he could also sell “foot oil” and steam-pounded leather, “Chamois”. He also pursued a telephone/ telegraph business across the Atlantic, more on that below, but only after getting monopoly rights for 50 years.
Cooper managed to stay friends with those he competed with by paying license fees for any patents he used (he tried to negotiate low rates), or buying or selling the patent rights as seemed appropriate. He also licensed his patents, and rented out buildings he didn’t need. He rented at a rate of 7% of the sale price, a metric I’ve used myself, considering rental to be like buying on loan. There is a theory of stock-buying that matches this.
The story the telegraph cable across the Atlantic is instructive to seeing how the pieces fit together. The first significant underwater cable was not laid by Cooper, by a Canadian inventor, Frederick Gisborne. It was laid in 1852 between Prince Edward Island and New Brunswick. Through personal connections, Gisborne’s company got exclusive rights for 30 years, for this and for a cable that would go to Newfoundland, but he didn’t have the money or baking to make it happen. The first cable failed, and Gisborne ran out of money and support. Only his exclusive rights remained. This is the typical story of an inventor/ engineer/businessman who has to rely on other peoples’ money and patience.
A few months after the failure, a friend of Cooper’s, Cyrus Field, convinced Cooper that good money could be made, and public good could be done, if Cooper could lay such a cable all the way to London. One thing that attracted Cooper to the project was that the cable could be made as an insulated iron-copper rope in Cooper’s own factory. Cooper, Field, and some partners (see painting below) bought Gisborne’s company, along with their exclusive rights, and formed a new company, The New York, Newfoundland & London Telegraph Company, see charter here. The founders are imagined* with a globe and a section of cable sitting on their table. Gisborne, though not shown in the painting, was a charter member, and made chief engineer. Cooper was president. He also traveled on the boat with Gisborne to lay the cable across the St. Lawrence – just to be sure he knew what was going on. This cable provided a trial for The Trans Atlantic cable.
The founding individuals to lay a transatlantic cable. Peter Cooper at left is the chairman, Cyrus Field is standing, Samuel Morse is at the back. Frederic Gisborne, a founder, does not appear in the paining. Typical.
Samuel Morse was hired as an electrician; he is pictured in the painting, but was not a charter member. Part of the problem with Morse was that he owned the patent on Morse-telegraphy, and Cooper didn’t want to pay his “exorbitant” fees. So Cooper and Field bought an alternative telegraph patent from David Hughes, a Kentucky school teacher. This telegraph system used tones instead of clicks and printed whole letters at a time. By hiring Morse, but not his patents, Cooper saved money, while retaining Morse’s friendship and expertise. The alternative could have been a nasty spat. Their telegraph company sub-licensed Hughes’s tone-method a group of western telegraph owners, “The Western Union,” who used it for many years, producing the distinctive Western Union Telegrams. With enough money in hand and credibility from the Canadian trial, the group secured 50 years monopoly rights for a telegraph line across the Atlantic. Laying the cable took many years, with semi-failed attempts in 1857, 1858, and 1865. When the eventual success came in 1866, the 50 years’ monopoly rights they’d secured meant that they made money from the start. They could treat workers fairly. Marconi would discover that Cooper wrote a good contract; his wireless telegraph required a widely different route.
I should also note that Peter Cooper was politically active: he started as a Democrat, helped form the Republican Party, bringing Lincoln to speak in NY for the first time, and ended up founding the Greenback-Labor Party, running for president as a Greenback. He was strongly for tariffs, and strongly against inflation. He said that the dollar should have the same value for all time for the same reason that the foot should have the same length and the pound the same weight. I have written in favor of tariffs off and on. They help keep manufacturing in America, and help insure that those who require French wine or German cars pay the majority of US taxes. They are also a non-violent vehicle for foreign policy.
Operating under these principles, through patents and taxed monopolies, Peter Cooper died wealthy, and liked. Liked by his workers, liked by much of the press, and by his family too, with children who turned out well. The children of rich people often turn out poorly. Carnegie’s children fought each other in court, Ford’s were miserable. Cooper’s children continued in business and politics, successfully and honorably, and in science/ engineering (Peter Coper Hewitt invented the power rectifier, sold to Westinghouse). The success of Peter Cooper’s free college, Cooper Union, influenced many of his friends to open similar institutions. Among his friends who did this were Carnegie, Pratt, Stevens, Rensselaer, and Vanderbilt. He stayed friends with them and with other inventors of the day, despite competing in business and politics. Most rich folks can not do this; they tend to develop big egos, and few principles.
Robert Buxbaum, November 30, 2022. I find the painting interesting. Why was it painted? Why is Gisborne not in it and Morse in the painting — sometimes described as vice President? The charter lists Morse as “electrician”, an employee. Chandler White, holding papers next to Cooper, was Vice President. My guess is that the painting was made to help promote the company and sell stock. They made special cigars with this image too. This essay started as a 5th grade project with my son. See a much earlier version here.
“Riding on the City of New Orleans Illinois Central Monday morning rail Fifteen cars and fifteen restless riders Three conductors and twenty-five sacks of mail All along the southbound odyssey The train pulls out at Kankakee Rolls along past houses, farms and fields Passin’ trains that have no names Freight yards full of old black men And the graveyards of the rusted automobiles…”
Every weekday, this train leaves Chicago at 9:00 PM and gets into New Orleans twenty hours later, at 5:00 PM. It’s a 925 mile trip at a 45 mph average: slow and money-losing, propped up by US taxes. Like much of US passenger rail, it “has the disappearing railroad blues.” It’s a train service that would embarrass the Bulgarians: One train a day?! 45 mph average speed!? It’s little wonder is that there are few riders, and that they are rail-enthusiasts: “the sons of Pullman porters, and the sons of engineers, Ride[ing] their father’s magic carpets made of steel.” The wonder, to me was that there was ever fifteen cars for these, “15 restless riders”.
A sack of mail being picked up on the fly.
I would be happy to see more trips and a faster speed, at an average speed of at least 60 mph. This would require 85 mph or higher between stops, but it would save on salaries, and it would bring in some new customers. But even if these higher speeds cost nothing extra, in net, you’d still need something more to make the trip profitable; a lot more if the goal is to add another train. Air-traffic will always be faster, and the automobile, more convenient. I find a clue to profitability in the fifteen cars of the song and in the sacks of mail.
Unless I’m mistaken, mail traffic was at least as profitable as passenger traffic, and those “twenty-five sacks of mail” were either very large, or just the number on-loaded at Kankakee. Passenger trains like ‘the city of New Orleans’ were the main mail carriers till the late 1970s, a situation that ended when union disputes made it unprofitable. Still, I suspect that mail might be profitable again if we used passenger trains only for fast mail — priority and first class — and if we had real fast mail again. We currently use trucks and freight trans for virtually all US mail, we do not have a direct distribution system. The result is that US mail is vastly slower than it had been. First class mail used to arrive in a day or two, like UPS now. But these days the post office claims 2 to 4 business days for “priority mail,” and ebay guarantees priority delivery time “within eight business days”. That’s two weeks in normal language. Surely there is room for a faster version. It costs $7.35 for a priority envelope and $12.80 for a priority package (medium box, fixed price). That’s hardly less than UPS charges.
Last day of rail post service New York to Washington, DC. .June 30, 1977.
Passenger trains could speed our slow mail a lot, if it were used for this, even with these slow speeds. The City of New Orleans makes this trip in less than a day, with connections available to major cities across the US. If priority mail went north-south in under one day, people would use it more, and that could make the whole operation profitable. Trains are far cheaper than trucks when you are dealing with large volumes; there are fewer drivers per weight, and less energy use per weight. Still there are logistical issues to making this work, and you want to move away from having many post men handling individual sacks, I think. There are logistical advantages to on-loading and off-loading much larger packages and to the use of a system of standard sizes on a moving conveyor.
How would a revised mail service work? I’d suggest using a version of intermodal logistics. Currently this route consists of 20 stops including the first and last, Chicago and New Orleans. This suggests an average distance between stops of 49 Miles. Until the mid 70s, , mail would be dropped off and picked up at every stop, with hand sorting onboard and some additional on-off done on-the-fly using sacks and hooks, see picture above. For a modern version, I would suggest the same number of passenger stops, but fewer mail pick ups and drop offs, perhaps only 1/3 as many. These would be larger weight, a ton or more, with no hand sorting. I’d suggest mail drop offs and pick ups every 155 miles or so, and only of intermodal containers or pods: ten to 40 foot lengths. These containers plus their contents would weigh between 2,500 and 25,000 pounds each. They would travel on flatcars at the rear of the passenger cars, and contain first class and priority mail only. Otherwise, what are you getting for the extra cost?
The city of New Orleans would still leave Chicago with six passenger cars, but now these would be followed by eight to ten flatcars holding six or more containers. They’d drop off one of the containers at a stop around the 150 mile mark, likely Champaign Urbana, and pick up five or so more (they’d now have ten). Champaign Urbana is a major east-west intermodal stop, by the way. I’d suggest the use of six or more heavy forklifts to speed the process. At the next mail-stop, Centralia, two containers might come off and four or more might come on. Centralia is near St. Louis, itself a major rail hub for trains going west. See map below. The next mail stop might be Memphis. Though it’s not shown as such, Memphis is a major east-west rail hub; it’s a hub for freight. A stripped down mail-stop version of passenger train mail like this seems quite do-able — to me at least. It could be quite profitable, too.
Amtrak Passenger rail map. The city of New Orleans is the dark blue line going north-south in the middle of the map.
Intermodal, flat-bed trucks would take the mail to sorting locations, and from there to distribution points. To speed things, the containers might hold pre-sorted sacks of mail. Intermodal trucks might also carry some full containers east and west e.g. from Centralia to St. Louis, and some full flatcars could be switched on and off too. Full cars could be switched at the end, in New Orleans for travel east and west, or in the middle. There is a line about “Changing cars in Memphis Tennessee.” I imagine this relates to full carloads of mail joining or leaving the train in Memphis. Some of these full intermodal containers could take priority mail east and west. One day mail to Atlanta, and Houston would be nice. California in two days. That could be a money maker.
At this point, I would like to mention “super-fast” rail. The top speeds of these TGV’s “Transports of Grande Vitess” are in the range of 160 mph (265 km/hr) but the average speeds are lower because of curves and the need to stop. The average speeds are roughly 125 mph on the major routes in Europe, but they require special rails and rail beds. My sense is that this sort of special-use improvement is not worth the cost for US rail traffic. While 60 -90 mph can be handled on the same rails that carry freight, the need for dedicated track comes with a doubling of land and maintenance costs. And what do you have when you have it? The bullet rail is still less than half as fast as air travel. At an average speed of 125 mph, the trip between Chicago and New Orleans would take seven hours. For business travelers, this is not an attractive alternative to a two hour flight, and it is not well suited for intermodal mail. The fuel costs are unlikely to be lower than air travel, and there is no easy way to put mail on or off a TGV. Mail en-route would slow the 125 mph speed further, and the use of intermodal containers would dramatically increase the drag and fuel cost. Air travel has less drag because air density is lower at high altitude.
Meanwhile, at 60 mph average speeds, train travel can be quite profitable. Energy use is 1/4 as high at 60 mph average as at 120 mph. An increase of average speed to 60 mph would barely raise the energy use compared to TGV, but it would shorten the trip by five hours. The new, 15 hour version of “The City of New Orleans” would not be competitive for business travel, but it would be attractive for tourists, and certainly for mail. Having fewer hours of conductor/ engineer time would save personnel costs, and the extra ridership should allow the price to stay as it is, $135 one-way. A tourist might easily spend $135 for this overnight trip: leaving Chicago after dinner and arriving at noon the next day. This is far nicer than arriving at 5:00 PM, “when the day is done.”
Robert Buxbaum, June 21, 2019. One summer during graduate school, I worked in the mail room of a bank, stamping envelopes and sorting them by zip code into rubber-band tied bundles. The system I propose here is a larger-scale version of that, with pre-sorted mail bags replacing the rubber bands, and intermodal containers replacing the sacks we put them in.
I’ve come to conclude that airplane travel makes a lot more sense than high-speed trains. Consider the marginal energy cost of a 90kg (200 lb) person getting on a 737-800, the most commonly flown commercial jet in US service. For this plane, the ratio of lift/drag at cruise speed is 19, suggesting an average value of 15 or so for a 1 hr trip when you include take-off and landing. The energy cost of his trip is related to the cost of jet fuel, about $3.20/gallon, or about $1/kg. The heat energy content of jet fuel is 44 MJ/kg. Assuming an average engine efficiency of 21%, we calculate a motive-energy cost of 1.1 x 10-7 $/J. The amount of energy per mile is just force times distance. Force is the person’s weight in (in Newtons) divided by 15, the lift/drag ratio. The energy use per mile (1609 m) is 90*9.8*1609/15 = 94,600 J. Multiplying by the $-per-Joule we find the marginal cost is 1¢ per mile: virtually nothing compared to driving.
The Wright brothers testing their gliders in 1901 (left) and 1902 (right). The angle of the tether reflects a dramatic improvement in lift-to-drag ratio; the marginal cost per mile is inversely proportional to the lift-to-drag ratio.
The marginal cost of 1¢/passenger mile explains why airplanes offer crazy-low, fares to fill seats. But this is just the marginal cost. The average energy cost is higher since it includes the weight of the plane. On a reasonably full 737 flight, the passengers and luggage weigh about 1/4 as much as the plane and its fuel. Effectively, each passenger weighs 800 lbs, suggesting a 4¢/mile energy cost, or $20 of energy per passenger for the 500 mile flight from Detroit to NY. Though the fuel rate of burn is high, about 5000 lbs/hr, the mpg is high because of the high speed and the high number of passengers. The 737 gets somewhat more than 80 passenger miles per gallon, far less than the typical person driving — and the 747 does better yet.
The average passengers must pay more than $20 for a flight to cover wages, capital, interest, profit, taxes, and landing fees. Still, one can see how discount airlines could make money if they have a good deal with a hub airport, one that allows them low landing fees and allows them to buy fuel at near cost.
Compare this to any proposed super-fast or Mag-lev train. Over any significant distance, the plane will be cheaper, faster, and as energy-efficient. Current US passenger trains, when fairly full, boast a fuel economy of 200 passenger miles per gallon, but they are rarely full. Currently, they take some 15 hours to go Detroit to NY, in part because they go slow, and in part because they go via longer routes, visiting Toronto and Montreal in this case, with many stops along the way. With this long route, even if the train got 150 passenger mpg, the 750 mile trip would use 5 gallons per passenger, compared to 6.25 for the flight above. This is a savings of $5, at a cost of 20 hours of a passenger’s life. Even train speeds were doubled, the trip would still take 10 hours including stops, and the energy cost would be higher. As for price, beyond the costs of wages, capital, interest, profit, taxes, and depot fees, trains have to add the cost of new track and track upkeep. Wages too will be higher because the trip takes longer. While I’d be happy to see better train signaling to allow passenger trains to go 100 mph on current, freight-compatible lines, I can’t see the benefit of government-funded super-track for 150+ mph trains that will still take 10 hours and will still be half-full.
Something else removing my enthusiasm for super trains is the appearance of new short take-off and landing jets. Some years ago, I noted that Detroit’s Coleman Young airport no longer has commercial traffic because its runway was too short, 1550 m. I’m happy to report that Bombardier’s new CS100s should make small airports like this usable. A CS100 will hold 120 passengers, requires only 1509m of runway, and is quiet enough for city use. Similarly, the venerable Q-400 carries 72 passengers and requires 1425m. The economics of these planes is such that it’s hard to imagine mag-lev beating them for the proposed US high-speed train routes: Dallas to Houston; LA to San José to San Francisco; or Chicago-Detroit-Toledo-Cleveland-Pittsburgh. So far US has kept out these planes because Boeing claims unfair competition, but I trust that this is just a delay. For shorter trips, I note that modern busses are as fast and energy-efficient as trains, and far cheaper because they share the road costs with cars and trucks.
If the US does want to spend money, I’d suggest improving inner-city airports, and to improve roads for higher speed car and bus traffic. If you want low pollution transport at high efficiency, how about hydrogen hybrid buses? The range is high and the cost per passenger mile remains low because busses use very little energy per passenger mile.
Robert Buxbaum, October 30, 2017. I taught engineering for 10 years at Michigan State, and my company, REB Research, makes hydrogen generators and hydrogen purifiers.
