4 ms·

Do you have any source or more information on the $100/hr figure? That seems shockingly high to me. It only costs about twice or three times that to run a small

by aftbit 1y ago

Do you have any source or more information on the $100/hr figure? That seems shockingly high to me. It only costs about twice or three times that to run a small airplane or a farming combine.

mousethatroared 1y ago
Is it surprising though? Without looking up the data, off the top of my head. The bus driver needs a commercial license with air brakes, is a public employee and has benefits. He has to be making 75k/year + overhead. Let's say overhead is 50% $56.25 / hr. Then there's the diesel cost. A large bus must get ~ 10 mpg highway, but a city bus is all stop and go - disastrous for a vehicle as massive as a bus. Let's say it gets 4 mpg. $4/gal diesel * 30 mph average speed / 4 mpg = $30 / hr on diesel. We're at $86.26/hr. You could argue my driver makes too much, and my mpg is too low, but I havent included: - routine maintenance - fixing broken vehicles - cleaning - amortization So, play with the numbers if you will; but $100/hr has to be a good, round estimate, for running costs.
- rsynnott 1y ago
  > Then there's the diesel cost. A large bus must get ~ 10 mpg highway, but a city bus is all stop and go - disastrous for a vehicle as massive as a bus. Let's say it gets 4 mpg. Increasingly, most buses would be either electric, or heavy hybrid (ie electric with a diesel generator). But also, consider the money they take in. My local bus system's buses take up to 100 people. The charge is 2 euro for a journey where the last leg starts within 90 minutes of the first leg, on any mode of transport. However in practice the average journey would be in the 30 min range. So if the buses are constantly full, that's 400 euro per hour takings! Of course, it's not really that high; the buses are not always full, some people are using monthly or annual tickets, which are cheaper, some people are kids or over 65 or otherwise get cheap or free travel, the trains and trams also have to be paid for, and so on. But it's sufficient that they were actually able to cut the price (it used to be up to 3.50 for a single bus journey); the increased use from the cheaper simpler system offset the reduction in revenue per journey.
  - mousethatroared 1y ago
    The problem with buses is that utilization is very low. Most buses, most of the time, run near empty. This also significantly i creases their overall passenger mile GHG emissions. Hybrid buses and CNG probably make sense. But I doubt, fully electric buses make sense: as long as dispatch-able power (ie your marginal producer) is a thermal plant you get 60ish% thermal efficiency at best minus transformer and transmission losses. A bus engine for use in a hybrid can be made more than 40% efficient (miller cycle, high compression, high octane CNG, full throttle PWM operation, etc).
    - rsynnott 1y ago
      > The problem with buses is that utilization is very low. Most buses, most of the time, run near empty. Huh. That doesn't resemble my experience, except for rural/small-town services, which are very much provided as a form of subsidy, not a viable business. > But I doubt, fully electric buses make sense: as long as dispatch-able power (ie your marginal producer) is a thermal plant you get 60ish% thermal efficiency at best minus transformer and transmission losses. That's still quite a bit better than diesel engines, where for realistic engines you're talking about 40% _in ideal conditions_, but much worse in stop-start conditions (you will do better with hybrids, granted). Gas also have considerably lower CO2 intensity per thermal watt than diesel does (your fossil fuel electricity production is probably mostly gas in most countries). But, also, in countries with a lot of unreliable renewables, buses charging overnight can be used as a power sink. For instance, in Ireland, our wind generation can be anything from almost nothing to greater than total system demand; reasonably often, wind turbines actually have to be stopped to reduce output, especially at night. At that point, charging the bus is for practical purposes free, or may even have a modest negative cost (the network will sometimes pay for power consumption).
      - mousethatroared 1y ago
        "That's still quite a bit better than diesel engines, where for realistic engines you're talking about 40% _in ideal conditions_" and so on Which is where hybrid drive trains and PWM comes in. Run the engine at its ideal and only at its ideal with no care for the actual load requested. Furthermore I mentioned CNG - ie methane. Methane has more energy per CO2 gram than any hydrocarbon and has an insanely high octane number -> it can run an Otto cycle at diesel compression ratios. Run it as a miller cycle and the thermal efficiency starts to go up even highed. Really my 40% is a low ball of what is possible in ICEs to not offend anyone's preconceptions. F1 claims to have achieved >50% thermal efficiency in a race engine but Im usually loath to mention that because of their secrecy and therefore lack of indee verification. And no one talks that lines and transmission is lossy. No one talks that dispach-able power is often coal or oil. No one talks about the environmental and social cost of batteries. Hybrids ameliorate (the most, btw) just about every aspect of this while minimizing external costs
- mapt 1y ago
  > Then there's the diesel cost. A large bus must get ~ 10 mpg highway, but a city bus is all stop and go - disastrous for a vehicle as massive as a bus. Let's say it gets 4 mpg. $4/gal diesel * 30 mph average speed / 4 mpg = $30 / hr on diesel. We've already got decent electric bus options implemented in a number of cities, and they're only going to get better. That's before you consider hooking them up to wires like a sensible transit network. Municipal fleets often make it a point to use alternative energy with buses, like CNG before batteries were a practical option. They do it for public image, because of the urban air quality issues with old-school diesel exhaust, and for cost reasons. A more interesting point is pavement. Public buses, garbage trucks, and schoolbuses are some of the most significant non-weather-related causes of road wear, and this is only going to get worse the heavier the axle weight if you try to run long-range battery banks. Road wear scales with axle weight raised to the fourth power. Arguably there is a case to be made for the articulated or even bi-articulated designs if it allowed you to drop axle weight, with significant benefit to the Packed Like Sardines problem. Articulated EVs have a lot more freedom to redistribute the weight and to power individual axles more intelligently.
  - mousethatroared 1y ago
    Its not obvious to me that EV buses (or any EV vehicle, frankly) make sense. [1] Hybrid and CNG make a lot of sense though. [1] Run the math and hybrids come ahead of EVs in personal vehicles for GHG emissions. For buses it would be more skewed in favor of hybrids.
bluGill 1y ago
In the US every transit agency published their costs to the FTA. I looked that data up about 5 years ago, and I can't remember how to search it, but it should be online if you want to figure it out. (unless Trump has removed that?)

by aftbit 1y ago

Do you have any source or more information on the $100/hr figure? That seems shockingly high to me. It only costs about twice or three times that to run a small airplane or a farming combine.

mousethatroared 1y ago

Is it surprising though? Without looking up the data, off the top of my head. The bus driver needs a commercial license with air brakes, is a public employee and has benefits. He has to be making 75k/year + overhead. Let's say overhead is 50% $56.25 / hr. Then there's the diesel cost. A large bus must get ~ 10 mpg highway, but a city bus is all stop and go - disastrous for a vehicle as massive as a bus. Let's say it gets 4 mpg. $4/gal diesel * 30 mph average speed / 4 mpg = $30 / hr on diesel. We're at $86.26/hr. You could argue my driver makes too much, and my mpg is too low, but I havent included: - routine maintenance - fixing broken vehicles - cleaning - amortization So, play with the numbers if you will; but $100/hr has to be a good, round estimate, for running costs.

rsynnott 1y ago
> Then there's the diesel cost. A large bus must get ~ 10 mpg highway, but a city bus is all stop and go - disastrous for a vehicle as massive as a bus. Let's say it gets 4 mpg. Increasingly, most buses would be either electric, or heavy hybrid (ie electric with a diesel generator). But also, consider the money they take in. My local bus system's buses take up to 100 people. The charge is 2 euro for a journey where the last leg starts within 90 minutes of the first leg, on any mode of transport. However in practice the average journey would be in the 30 min range. So if the buses are constantly full, that's 400 euro per hour takings! Of course, it's not really that high; the buses are not always full, some people are using monthly or annual tickets, which are cheaper, some people are kids or over 65 or otherwise get cheap or free travel, the trains and trams also have to be paid for, and so on. But it's sufficient that they were actually able to cut the price (it used to be up to 3.50 for a single bus journey); the increased use from the cheaper simpler system offset the reduction in revenue per journey.
- mousethatroared 1y ago
  The problem with buses is that utilization is very low. Most buses, most of the time, run near empty. This also significantly i creases their overall passenger mile GHG emissions. Hybrid buses and CNG probably make sense. But I doubt, fully electric buses make sense: as long as dispatch-able power (ie your marginal producer) is a thermal plant you get 60ish% thermal efficiency at best minus transformer and transmission losses. A bus engine for use in a hybrid can be made more than 40% efficient (miller cycle, high compression, high octane CNG, full throttle PWM operation, etc).
  - rsynnott 1y ago
    > The problem with buses is that utilization is very low. Most buses, most of the time, run near empty. Huh. That doesn't resemble my experience, except for rural/small-town services, which are very much provided as a form of subsidy, not a viable business. > But I doubt, fully electric buses make sense: as long as dispatch-able power (ie your marginal producer) is a thermal plant you get 60ish% thermal efficiency at best minus transformer and transmission losses. That's still quite a bit better than diesel engines, where for realistic engines you're talking about 40% _in ideal conditions_, but much worse in stop-start conditions (you will do better with hybrids, granted). Gas also have considerably lower CO2 intensity per thermal watt than diesel does (your fossil fuel electricity production is probably mostly gas in most countries). But, also, in countries with a lot of unreliable renewables, buses charging overnight can be used as a power sink. For instance, in Ireland, our wind generation can be anything from almost nothing to greater than total system demand; reasonably often, wind turbines actually have to be stopped to reduce output, especially at night. At that point, charging the bus is for practical purposes free, or may even have a modest negative cost (the network will sometimes pay for power consumption).
    - mousethatroared 1y ago
      "That's still quite a bit better than diesel engines, where for realistic engines you're talking about 40% _in ideal conditions_" and so on Which is where hybrid drive trains and PWM comes in. Run the engine at its ideal and only at its ideal with no care for the actual load requested. Furthermore I mentioned CNG - ie methane. Methane has more energy per CO2 gram than any hydrocarbon and has an insanely high octane number -> it can run an Otto cycle at diesel compression ratios. Run it as a miller cycle and the thermal efficiency starts to go up even highed. Really my 40% is a low ball of what is possible in ICEs to not offend anyone's preconceptions. F1 claims to have achieved >50% thermal efficiency in a race engine but Im usually loath to mention that because of their secrecy and therefore lack of indee verification. And no one talks that lines and transmission is lossy. No one talks that dispach-able power is often coal or oil. No one talks about the environmental and social cost of batteries. Hybrids ameliorate (the most, btw) just about every aspect of this while minimizing external costs
mapt 1y ago
> Then there's the diesel cost. A large bus must get ~ 10 mpg highway, but a city bus is all stop and go - disastrous for a vehicle as massive as a bus. Let's say it gets 4 mpg. $4/gal diesel * 30 mph average speed / 4 mpg = $30 / hr on diesel. We've already got decent electric bus options implemented in a number of cities, and they're only going to get better. That's before you consider hooking them up to wires like a sensible transit network. Municipal fleets often make it a point to use alternative energy with buses, like CNG before batteries were a practical option. They do it for public image, because of the urban air quality issues with old-school diesel exhaust, and for cost reasons. A more interesting point is pavement. Public buses, garbage trucks, and schoolbuses are some of the most significant non-weather-related causes of road wear, and this is only going to get worse the heavier the axle weight if you try to run long-range battery banks. Road wear scales with axle weight raised to the fourth power. Arguably there is a case to be made for the articulated or even bi-articulated designs if it allowed you to drop axle weight, with significant benefit to the Packed Like Sardines problem. Articulated EVs have a lot more freedom to redistribute the weight and to power individual axles more intelligently.
- mousethatroared 1y ago
  Its not obvious to me that EV buses (or any EV vehicle, frankly) make sense. [1] Hybrid and CNG make a lot of sense though. [1] Run the math and hybrids come ahead of EVs in personal vehicles for GHG emissions. For buses it would be more skewed in favor of hybrids.

bluGill 1y ago

In the US every transit agency published their costs to the FTA. I looked that data up about 5 years ago, and I can't remember how to search it, but it should be online if you want to figure it out. (unless Trump has removed that?)