Rail advocates say we need to spend hundreds of billions of dollars on high-speed rail to reduce the greenhouse gas emissions from flying. But there is probably a more cost-effective way of reducing the greenhouse gas emissions from flying, such as using aviation fuel that emits fewer net greenhouse gases.
Of course, there’s no reason to think that high-speed rail would reduce greenhouse gas emissions anyway. The best study on the issue found that the huge amount of greenhouse gases emitted during construction would require 71 years of savings to balance out. But rail lines must be extensively rebuilt every 20 to 30 years, and I don’t see that the study factored the greenhouse gas emissions of such reconstruction into the analysis.
Even if high-speed rail could be built without emitting any greenhouse gases, there are ways of reducing greenhouse gases that are far less expensive. Recently, United Airlines flew a regularly scheduled plane from Chicago to Washington that exclusively used biofuels — known as sustainable aviation fuels — in one of its two engines. Federal Aviation Administration rules limit the use of biofuels to half the fuel on a commercial plane, but biofuels have been used for 100 percent of the fuels for some non-commercial test flights.
A skeptical view of sustainable aviation fuels points out that United got its fuel from corn that was grown for that purpose. It worries that “there is not enough land to keep us all up in the air.”
That’s an exaggeration: an acre of corn can produce around 460 gallons of fuel, so it would take a little more than 56 million acres of land to produce the 26 billion gallons of fuel used by domestic airlines in 2019. Considering that the United States has more than a billion acres of agricultural lands and we only grow crops on about a third of them, we have land to spare for growing corn. But growing corn for biofuels ends up emitting greenhouse gases too, so may not be the most efficient way to do it.
The same article suggests the other source of biofuels is “fats, oil, and grease,” but adds that “there is limited waste grease and oil out there, and only so much lard and beef tallow available.” However, a third source of biofuels could come from waste or by-products of agriculture and forestry, such as the branches leftover after cutting trees or the small trees thinned from a forest to allow the remaining trees grow faster.
This report from the Department of Energy estimates that, at a price of $60 a ton, U.S. forests and farms would provide more than 340 million tons of such by-products per year. At a conservative 50 gallons of biofuel per ton of wood or other organic material, that could supply about 17 million gallons of fuel per year, or about two-thirds of what was used for domestic air travel in 2019. With a raw material price of $1.20 per gallon, biofuels will cost more than petroleum-based fuels, but this Department of Energy report explores ways of reducing that cost.
Thus, a combination of corn and forest/agricultural waste could provide enough sustainable aviation fuels to meet our present and future needs without devoting too many acres to corn production. The fuel produced from such wastes might cost more than petroleum-based aviation fuel, but that extra cost would be a lot less than the cost of building high-speed rail lines all over the United States.
Burning crop residue to fly from Chicago to Denver is no different than burning trees to generate electricity which is almost the same as (the time scales differ) burning coal or oil to generate electricity. The crop (trees, corn) removed CO2 from the atmosphere and burning the crop (trees, corn) returns it to the atmosphere.
If the crop (trees, corn) is left on the ground it will ultimately sequester carbon.
All of this burning trees and crops just delays the ultimate solution — nuclear power. But it makes some people feel better.
We should never do anything so foolish as use food for fuel.
a) Ethanol has half the energy consent of jet fuel. If US airlines used 26 billion gallons of jet fuel, you’ll need ~50+ billion gallons of ethanol.
b) There isn’t any new arable farm land available. It’s maxed out. The only wiggle room are small productivity gains that happen. Most entirely, you’re just taking food out of the supply and throwing it at fuel.
c) The US around 3/4 of a trillion acres of arable land.
If one were to replace jet fuel with ethanol, you’re looking at dedicating 10%-20% of arable land in the US not to producing food to eat but to fly people in Nashville for a bachelorette party.
WHat we’d be doing is taking a system that has a lot of wiggle room, one we can NOT live without, food, and shrinking that food supply 10-20%. And that’s assuming good weather.
Worse, you’ll have taken a 2nd system and made it subject to the whims of the weather.
You’ll have made not one but 2 system way more randomly fragile. Not wise; not wise at all.
a) The above is probably off by a zero
b) The above is off in that this USDA report claims there’s 400,000,000 acres of cropland.
https://www.nass.usda.gov/Publications/Highlights/2014/Highlights_Farms_and_Farmland.pdf
There’s all sorts of numbers & there all look like a huge chunk of food would be used for fuel.
“Ben.”
“Mr. McGuire.”
“I want to say one word to you. Just one word.”
“Yes, sir?”
“Hydrogen.”
why not just use Zoom?
It doesn’t matter…….namely the biggest difference is
Whatever technology the aviation industry works on, will be financed by it’s own endeavors using their own capital. If it fails it’s money down the drain, but not taxpayer money…..
The 1930’s saw the end of the airship era. Blimps and Airships however may make a comeback. An Ohio company Ohio Airships, combines the advantages of air cargo while significantly reducing ecological problems. They achieve this by designing slow cargo airships, called “Dynalifters”. These air vessels mix the travel concepts of planes and Zeppelins. The company completed 4 conceptual designs for four different sizes. All designs are equipped with detachable cargo pods for rapid loading and off-loading, and a prototype with a length of 37 metres has already been built and tested.
They’re not blimps, they do not float away without a tether. The Dynalift is a airship/plane hybrid, it uses the helium/air mixed bag buoyancy to reduce most of the aircrafts weight penalty but it’s not light enough to float. The airship has wings and engines and wheels and takes off and lands as passenger aircrafts do albeit at a slower pace. The aircraft do not fly at stratospheric altitudes and can navigate safely in as little as 2,000 feet or less. It’s prototype top speed is 200 km/h or 124 miles an hour, while four times slower than a jet it uses a fraction of the fuel to travel the same distances. The passenger gondola offers wider floor plans than jet’s, a 747 is 240 inches wide (20+ feet) a passenger gondola can be over 25 feet wide and windows the size of house windows because cabins don’t require pressurization and open floor plans means no coach style seating.
Speed’s approaching 150-200 mph are doable, but the biggest advantage is efficiency. A dynalifter for comparisons say can use the a C130’s engines and wings and for the same fuel volume move 12x the cargo volume the same distance. In otherwords, per passenger mile, 6x more fuel efficient. Where 1/3 to half the price of a flight ticket is fuel consumed….
I’ve repeated before, but reason I bring it up is technological investment is minimal but the gains are substantial. A six fold increase in fuel economy savings is a 6 fold CO2 emissions reduction. Antiplanner mentions customers wont sacrifice “Time” for efficiency. They would if it saves money…….why else do people ride buses, buses are slower than trains and planes but they are cheaper. Dynalifter cuts fuel consumption considerably……1/3 to half the price of a plane ticket is the fuel consumed and fuel taxes.
It’s 1.85 tons of CO2 per ton of steel produced.
It’s 0.9 tons per ton of concrete produced.
A concrete railroad tie weighs 200 lbs average (1/10th of a short ton) with an average distance of 19 inches, requires 264,000 per 100 miles (33,000 tons of concrete) producing just shy of 30,000 tons of CO2 or 264 tons per mile. Steel rail weigh 115 lbs per yard, or 101 tons per mile or 374 tons of co2 per mile for the steel track. Laying HSR track; In other words 638 tons per mile (NOT including welding, transport, etc) average it 1000 tons per mile.
Aluminum (Planes) 11.5 tons CO2 per ton of aluminum with an airplane weighing 80 tons mostly aluminum, Boeing having delivered over 15,000 737’s.
The global aviation industry produces around 2% of all human-induced carbon dioxide.
Rail transportation emits about 0.2 pounds of greenhouse gases per passenger mile.
On average, a plane produces a little over 53 pounds per mile. Air travel produces 265 times the emissions per mile. US Airlines alone used 18.27 billion gallons of aviation fuel in 2019 producing 191 Million tons of emissions. That’s FAR greater than the construction co2 deficit of rail construction. GLOBAL Aviation emissions produce 1 Billion tons a year.
Like many economists and statisticians; Antiplanner uses per capita and averages but ignores basic concept of Physics. Assuming you mean a tonne – ie a metric tonne, 1000kg – the energy required to lift one tonne to a height of one meter is given by the equation ‘mgh’ – mass times the acceleration due to gravity times the height, so that’s 1000 * 9.8 * 1, or 9,800 Joules. Trains are order of magnitude more fuel efficient than planes, even empty. An electric train uses 30 Kilowatt-hours per train-mile at 12¢ per kWh would have a fuel cost of only $3.60. 30 kwh is about the daily electric use of a US home and equals 108 Megajoules or 20.45 kilojoules to go one foot that weighs over 3000 tons. A modern 737 uses two CFM-6 turbine engines each producing 24000 lbs of thrust That’s over 74,000 horsepower. Or 54 Megawatts or uses 54,000 kilowatt hours or 194.4 gigajoules per hour (at cruise speed of 550 mph or 806.66 feet per second) of flying uses 66.9 kilojoules per foot to move a mere 86 tons only about 6-7 tons are passengers and luggage.
Fact is a plane uses over 1000x more energy to move the same unit of mass the same distance.
The fucking biofuel scam is a subsidized monster tha’ll never die.
While the first generation of biofuels wreaked havoc on food markets by diverting agriculture food staples into our gas tanks.
The second generation wreaked havoc on the environment, by diverting tropical nations into growing palm oils and jatropa to produce in home fuel blends by bulldozing the rainforests.
The third generation of biofuels will ruin both and make matters worse. The taxpayer funded debacles of ethanol and biodiesel made from food crops did more harm than good, the hope for finding a substitute for oil had shifted to algae and cellulose. Both of which are scams……..
plant matter and crops have to be planted, fertilized, harvested, transported, and converted; ALL those stages use energy predominantly using fossil energy.
All plant matter uses cellulose in it’s biology, It is too early to say whether or not cellulosic ethanol can ever be produced with a net energy gain as a result – at the moment, it is impossible. We can only hope that scientists will never succeed, because what we do know for sure is that cellulosic ethanol will be an even larger threat than the first generation of biofuels.
Cellulosic ethanol is made using inedible parts of the plant…stalks, roots and leaves. It can also be made of non-edible plants, like switchgrass or stuff like wood waste, branches, tree trimmings, conifer needles, shit like that…..sounds like a good approach. However this leaves behind one crucial element; THE SOIL. In nature, the concept of waste does not exist. “WASTE” is food in nature. The so-called “waste” that we plan to transform into fuel, is an essential element to keep the soil productive. Leaves, twigs and stalks, even whole fallen trees are decomposed by underground organisms, or munched on by bugs and invertebrates whose wastes (Poo) feed bacteria and fungi; which turn it into humus that can feed a next generation of plants and other organisms. If you take away this material, the soil will become less and less fertile until all you are left with is a mineral laden soil with no organic material, essentially desert soil. A process offset with more fossil based fertilizers, 2nd failure those fertilizers are good for plant growth but bad for soil health.
1st gen biofuels are a reversible, we can decide any time to change our minds and use corn, etc as edibles.
A similar deployment of cellulosic fuels would destroy our agricultural soils, without any chance to repair them afterwards. We will have mined the soil – a process that is largely irreversible except with 2-3 times more fertilizer than we currently use. When the soil is exhausted, even fertilizers are useless. Just ask a soil scientist…
https://www.culturechange.org/cms/index.php?option=com_content&task=view&id=107&Itemid=1
So “Algae” fuels , another croc cooked up by visionaires with no regards for physics. If algae don’t produce more energy than it takes to produce them, driving cars on algal fuel does not make much sense. And if they also use resources that are needed by agriculture, it’s a waste. To grow algae, you also need phosphorus (besides other minerals), an element that is very much needed by agriculture. Algae needs Huge volumes of water which agriculture also already demands. Some have proposed pumping seawater into sunny deserts but that is VERY energy intensive, which is why desalination plants are not built inland to meet Nevada, Arizona water needs. Just for measure it takes 1,400 to 20,000 liters of water to produce ONE liter of biofuel or 5,300 gallons to make ONE gallon of fuel. To make a million gallons a day in a serious manufacturing plant would need huge amounts of water.
@The Antiplanner
You ever hear of this?
https://www.youtube.com/watch?v=hL3AZGw9xZM
Lazyreader,
Your numbers comparing emissions from air and rail apply to freight but not passenger. A full freight car is two-thirds payload, while a full passenger car is 80 percent deadload. Since so much weight must be used to carry so little payload, the emissions from Diesel-powered passenger trains are roughly tied with air. (Electric train emissions depend on the source of electricity.)