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Besides driver salaries (ignored for private cars; major for public transit), the largest ongoing costs of any transportation system are usually fuel (energy usage) and maintenance. So ignoring the convenience factor for riders, SkyTran needs to be both energy-efficient and low-maintenance to reach its goal of profitability with reasonable fares and no subsidies. Does it?
To summarize yes, and yes. As shown below, a two-passenger SkyTran vehicle at 100 MPH needs only 1/10 the energy of a typical car going 65 MPH today. Also, SkyTran vehicles have almost no mechanical contact to cause wear and require regular maintenance.
Aerodynamic
SkyTran promises non-stop 100-MPH or 150-MPH transportation everywhere, making it perhaps the fastest practical local transportation systems ever invented. Since a car at 65 MPH already spends most of its engine's power overcoming air resistance and this "drag" increases quickly with speed; so how can it claim to still be ten times as efficient?
The two other factors in aerodynamic drag a degigner can control are the vehicle’s shape and frontal area. (the area of the vehicle that the oncoming air encounters). The main secret of SkyTran energy efficiency is getting rid of all the wasted area of a car or SUV that isn't carrying people. As the animation on the left humorously shows -- take away our huge unnecessary metal cocoons, and we don't need a whole freeway to travel on -- SkyTran vehicles provide a safe and realistic way to do this. (Note that reducing frontal area is the reason SkyTran's design places the passengers one behind another, similar to how people sit in a motorcycle -- sitting side by side would double the energy consumption.) Shape is much less important; still, SkyTran vehicles get another factor of 2 or so from better streamlining than cars.
Result: the energy required to travel in a 2-passenger SkyTran vehicle at 100 MPH is only 5 horsepower, or 3.6 kilowatts -- a couple of hair dryers.
Electric
Even good internal combustion engines waste two-thirds of the energy in gasoline producing waste heat. Stationary power plants are about twice as efficient, and efficient electric motors waste very little of this -- they can convert 90% of their power to energy of motion. They can also act as generators ("regenerative braking") when the car goes down a hill or slows down, recovering most of the energy used to accelerate them. Modern hybrids like the Prius can reclaim about 50% of the kinetic energy of the vehicle this way. These efficiencies are major motivations for the move to hybrids and electric vehicles, as well as electric trains and subways.
Unfortunately, cars need to carry their power source with them. Gasoline still has a much higher energy capacity per pound than today's best batteries -- this is the biggest efficiency penalty electric cars face today. Batteries with enough capacity to power a car for hundreds of miles are also expensive. For example in the Tesla Roadster which has a range of more than 200 miles, the battery pack alone has a cost of $20,000. SkyTran is powered by electricity from wires in the guideway. SkyTran vehicles each have a small emergency battery, but because SkyTran doesn’t rely on batteries for main power, SkyTran can be electrically powered without the problems associated with batteries.
Because they are powered by the guideway, Skytan vehicle can recapture up to 90% of their kinetic energy when they slow down, feeding the power back into the Skytran electric grid to be used by other vehicles. This "smart grid storage" uses a variety of fluctuating local sources -- the electricity produced by decelerating vehicles, wind power when the wind blows, and solar panels at midday -- to power vehicles, charge electric cars parked at stations, and feed power into the main electrical grid -- amd drawing it out again when needed. There must still be reserve capacity or temporary storage to handle peaks of demand, but it can be located anywhere in a wide vicinity.
Light-Weight
SkyTran vehicles weigh around 200 pounds. The average weight of cars in the US today is 4000 pounds, more than 20 times as heavy! [Source: NY Times]
While low weight is the core reason for SkyTran’s low construction and maintenance costs, weight also plays a part in the energy consumption of the vehicles. The more a vehicle weighs, the more energy is needed to accelerate it. SkyTran minimizes the impact of this consumption because it changes speed very infrequently (only around turns and at your final destination).
Magnetic Levitation
Low maintenance was a primary reason that SkyTran's designers switched from wheels to magnetic levitation suspension. For cars, buses and subway trains to be safe, they need regular maintenance to replace their many mechanical parts when they wear out. Maintenance would be much more of a problem at 100 MPH or even faster. In contrast, magnetic levitation and linear electric motors produce no wear. Vehicles and track need do need inspections (probably mostly automatic) to ensure that they remain in alignment. Whenever a vehicle's 6G emergency brakes are used, both the vehicle and the track will need adjustment (this kind of extreme emergency would probably have resulted in an accident for a car).
The weight of a vehicle also affects its magnetic resistance. In a car, the act of its rubber tires gripping the road and deforming on contact causes a resistive force on the car. This resistive force is called rolling resistance. SkyTran is levitated by magnets, and thus has no rolling resistance; however it does have a magnetic drag which is also a resistive force. The heavier the vehicle is, the more rolling resistance or magnetic drag it will have. Keeping SkyTran vehicles light keeps its magnetic drag down.
Another benefit of SkyTran’s passive maglev system is that the faster the vehicle goes, the less magnetic drag there is. Tires on roads consume about 10% of an automobile's fuel. In comparison, the magnetic drag will consume less than 4% of the energy used by SkyTran at 100 MPH -- an equivalent rolling resistance better than the best hand-sewn bicycle racing tires.
To summarize yes, and yes. As shown below, a two-passenger SkyTran vehicle at 100 MPH needs only 1/10 the energy of a typical car going 65 MPH today. Also, SkyTran vehicles have almost no mechanical contact to cause wear and require regular maintenance.
Aerodynamic
SkyTran promises non-stop 100-MPH or 150-MPH transportation everywhere, making it perhaps the fastest practical local transportation systems ever invented. Since a car at 65 MPH already spends most of its engine's power overcoming air resistance and this "drag" increases quickly with speed; so how can it claim to still be ten times as efficient?
The two other factors in aerodynamic drag a degigner can control are the vehicle’s shape and frontal area. (the area of the vehicle that the oncoming air encounters). The main secret of SkyTran energy efficiency is getting rid of all the wasted area of a car or SUV that isn't carrying people. As the animation on the left humorously shows -- take away our huge unnecessary metal cocoons, and we don't need a whole freeway to travel on -- SkyTran vehicles provide a safe and realistic way to do this. (Note that reducing frontal area is the reason SkyTran's design places the passengers one behind another, similar to how people sit in a motorcycle -- sitting side by side would double the energy consumption.) Shape is much less important; still, SkyTran vehicles get another factor of 2 or so from better streamlining than cars. Result: the energy required to travel in a 2-passenger SkyTran vehicle at 100 MPH is only 5 horsepower, or 3.6 kilowatts -- a couple of hair dryers.
Electric
Even good internal combustion engines waste two-thirds of the energy in gasoline producing waste heat. Stationary power plants are about twice as efficient, and efficient electric motors waste very little of this -- they can convert 90% of their power to energy of motion. They can also act as generators ("regenerative braking") when the car goes down a hill or slows down, recovering most of the energy used to accelerate them. Modern hybrids like the Prius can reclaim about 50% of the kinetic energy of the vehicle this way. These efficiencies are major motivations for the move to hybrids and electric vehicles, as well as electric trains and subways.
Unfortunately, cars need to carry their power source with them. Gasoline still has a much higher energy capacity per pound than today's best batteries -- this is the biggest efficiency penalty electric cars face today. Batteries with enough capacity to power a car for hundreds of miles are also expensive. For example in the Tesla Roadster which has a range of more than 200 miles, the battery pack alone has a cost of $20,000. SkyTran is powered by electricity from wires in the guideway. SkyTran vehicles each have a small emergency battery, but because SkyTran doesn’t rely on batteries for main power, SkyTran can be electrically powered without the problems associated with batteries.
Because they are powered by the guideway, Skytan vehicle can recapture up to 90% of their kinetic energy when they slow down, feeding the power back into the Skytran electric grid to be used by other vehicles. This "smart grid storage" uses a variety of fluctuating local sources -- the electricity produced by decelerating vehicles, wind power when the wind blows, and solar panels at midday -- to power vehicles, charge electric cars parked at stations, and feed power into the main electrical grid -- amd drawing it out again when needed. There must still be reserve capacity or temporary storage to handle peaks of demand, but it can be located anywhere in a wide vicinity.
Light-Weight
SkyTran vehicles weigh around 200 pounds. The average weight of cars in the US today is 4000 pounds, more than 20 times as heavy! [Source: NY Times]
While low weight is the core reason for SkyTran’s low construction and maintenance costs, weight also plays a part in the energy consumption of the vehicles. The more a vehicle weighs, the more energy is needed to accelerate it. SkyTran minimizes the impact of this consumption because it changes speed very infrequently (only around turns and at your final destination).
Magnetic Levitation
Low maintenance was a primary reason that SkyTran's designers switched from wheels to magnetic levitation suspension. For cars, buses and subway trains to be safe, they need regular maintenance to replace their many mechanical parts when they wear out. Maintenance would be much more of a problem at 100 MPH or even faster. In contrast, magnetic levitation and linear electric motors produce no wear. Vehicles and track need do need inspections (probably mostly automatic) to ensure that they remain in alignment. Whenever a vehicle's 6G emergency brakes are used, both the vehicle and the track will need adjustment (this kind of extreme emergency would probably have resulted in an accident for a car).The weight of a vehicle also affects its magnetic resistance. In a car, the act of its rubber tires gripping the road and deforming on contact causes a resistive force on the car. This resistive force is called rolling resistance. SkyTran is levitated by magnets, and thus has no rolling resistance; however it does have a magnetic drag which is also a resistive force. The heavier the vehicle is, the more rolling resistance or magnetic drag it will have. Keeping SkyTran vehicles light keeps its magnetic drag down.
Another benefit of SkyTran’s passive maglev system is that the faster the vehicle goes, the less magnetic drag there is. Tires on roads consume about 10% of an automobile's fuel. In comparison, the magnetic drag will consume less than 4% of the energy used by SkyTran at 100 MPH -- an equivalent rolling resistance better than the best hand-sewn bicycle racing tires.