fanuc2013 · 51-55, F
Our current freight trains are diesel- electric like a hybrid car, also many big ships use this method
zonavar68 · 56-60, M
@fanuc2013 Sorry when I said 'electric' I meant battery-electric. Not diesel electrc, or hybrid of any sort (internal combustion + battery powered) or anything using an internal combustion engine for primary propulsion.
ie. machines that require 'plugging in' or otherwise connecting to an electrical power source to recharge and be ready for more work.
ie. machines that require 'plugging in' or otherwise connecting to an electrical power source to recharge and be ready for more work.
swirlie · 31-35, F
I have already taken a ride in a Cessna 152 fully electric two-seater training airplane which arrived in Canada last summer. It has 4 hours of flight range which is exactly what it offers as a gasoline version and looks exactly the same.
The batteries are located inside both wings adjacent the fuselage and the airplane cruises just as fast as the gas version... about 100 mph, 160 Kph.
The batteries are located inside both wings adjacent the fuselage and the airplane cruises just as fast as the gas version... about 100 mph, 160 Kph.
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ArishMell · 70-79, M
@swirlie Thankyou for explaining it.
I'd also not realised the point in your reply to Zonavar, regarding landing weight.
The matter of a ship carrying less mass as the voyage decreases, somewhat echoes the introduction of mechanically powered ships in the 19C. Although they were fuelled by coal - shovelled by hand into boiler furnaces - many people at the time thought a trans-oceanic ship not possible because of the bulk and tonnage of the fuel needed.
I'd also not realised the point in your reply to Zonavar, regarding landing weight.
The matter of a ship carrying less mass as the voyage decreases, somewhat echoes the introduction of mechanically powered ships in the 19C. Although they were fuelled by coal - shovelled by hand into boiler furnaces - many people at the time thought a trans-oceanic ship not possible because of the bulk and tonnage of the fuel needed.
swirlie · 31-35, F
@ArishMell
Thanks for pointing that out. Let's try that one again here...
Is there anything in particular that you don't see clearly?
I'd also not realized the point in your reply to Zonavar, regarding landing weight.
Thanks for pointing that out. Let's try that one again here...
Electric charge is not tangible because it cannot be seen nor felt, which means the battery weight does not reduce as the charge is depleted, unlike diesel fuel tanks which slowly become empty on an ocean cargo vessel and therefore the weight of diesel is no longer carried.
The weight of a gallon of diesel fuel is about 8.5 pounds per Imperial gallon.
Military (or commercial) transport aircraft have the same issue. A transport aircraft has a maximum take-off weight (MTOW) that is far greater than it's maximum landing weight (MLW). This means that a transport category aircraft can takeoff overweight, but it cannot turn around and immediately land overweight without dumping fuel overboard. This is because landing overweight exceeds the maximum design capability of the aircraft should the aircraft touchdown with a vertical velocity greater than 2Gs, which would be categorized as a 'hard landing'.
When a jet fuel powered transport aircraft takes off fully loaded, it's gross weight diminishes as it's journey progresses, thereby making it easier for the aircraft to climb to higher altitudes where the cost per mile is significantly reduced do to the rarified air, hence less drag imposed upon the airframe, hence cheaper operating cost and longer range resulting.
If that transport aircraft were to be fitted with EV batteries instead of liquid fuel, the gross weight of the aircraft would never change because no solid EV battery fuel is being spent and therefore, the weight of the aircraft does not get lighter as the journey continues.
This means the aircraft would end up having a much SHORTER range capability than a jet-fuel based aircraft because it would not be getting lighter as the journey progressed and would therefore land at the same gross weight it took off at.
EV therefore, only works in pleasure craft where the efficiency of the craft in question is not based on the gross weight of the unit reducing as the journey progresses.
The weight of a gallon of diesel fuel is about 8.5 pounds per Imperial gallon.
Military (or commercial) transport aircraft have the same issue. A transport aircraft has a maximum take-off weight (MTOW) that is far greater than it's maximum landing weight (MLW). This means that a transport category aircraft can takeoff overweight, but it cannot turn around and immediately land overweight without dumping fuel overboard. This is because landing overweight exceeds the maximum design capability of the aircraft should the aircraft touchdown with a vertical velocity greater than 2Gs, which would be categorized as a 'hard landing'.
When a jet fuel powered transport aircraft takes off fully loaded, it's gross weight diminishes as it's journey progresses, thereby making it easier for the aircraft to climb to higher altitudes where the cost per mile is significantly reduced do to the rarified air, hence less drag imposed upon the airframe, hence cheaper operating cost and longer range resulting.
If that transport aircraft were to be fitted with EV batteries instead of liquid fuel, the gross weight of the aircraft would never change because no solid EV battery fuel is being spent and therefore, the weight of the aircraft does not get lighter as the journey continues.
This means the aircraft would end up having a much SHORTER range capability than a jet-fuel based aircraft because it would not be getting lighter as the journey progressed and would therefore land at the same gross weight it took off at.
EV therefore, only works in pleasure craft where the efficiency of the craft in question is not based on the gross weight of the unit reducing as the journey progresses.
Is there anything in particular that you don't see clearly?
swirlie · 31-35, F
@zonavar68
zonavar68, I wrote 15 full paragraphs explaining the answer to your question and you responded to my reply with a cursory 'push' of your heart button.
Did you understand even a single sentence that I wrote in response to your question?
How do you scale that up to full-size commercial or military transport aircraft? Remember that with small things (same with EV light vehicles) it can work ok with a few trade-off's, but for large scale transportation those trade-off's become massive problems to overcome.
zonavar68, I wrote 15 full paragraphs explaining the answer to your question and you responded to my reply with a cursory 'push' of your heart button.
Did you understand even a single sentence that I wrote in response to your question?
ArishMell · 70-79, M
I assume you mean by pure battery power.
Long-distance heavy goods vehicles: probably not although companies like Scania are developing them.
Ironically, small (up to about 3t) battery-electric wagons were common in many European and American cities in the 1890s-1900s, mainly used to shuttle freight between railway goods-yards and local businesses.
Among them were many battery-electric, private cars, too; and those were allowed on the roads in London's Royal Parks from which these new-fangled, noisy, smelly, petroleum-spirit fueled equivalents were barred!
Trains. Yes, at least for passenger-trains. It takes far less power to accelerate a given load from rest to a set speed, and maintain that speed, on rails than on roads; and experiments with battery-electric traction are under way.
The world's first public-carrying trials of such started recently on a short line in the London suburbs.
Since Diesel multiple-unit trains with the engines under the coach floors are already commonplace, I see no reason against battery-electric equivalents replacing the DMU for inter-city and suburban routes.
Whether a BEMU carrying, say, 200 passengers would manage the Nullarbor Straight on a single charge, at night with the coach lights and heaters on, remains to be seen! (Steam locomotives had to stop for water part-way, so why not a recharging stop?)
Aircraft: There are already experiments, mainly in Sweden I think, on electrically-powered aeroplanes of limited capacity for short flights. No-one proposes such for intercontinental flight; but the real question there is need for so many flights in the first place.
Ships: Not batteries but fuel-cells perhaps. A large ship requires enormous power to push it through the water, and so far, using batteries for vessels is limited to slow-moving leisure and tourist craft on inland waterways.
Long-distance heavy goods vehicles: probably not although companies like Scania are developing them.
Ironically, small (up to about 3t) battery-electric wagons were common in many European and American cities in the 1890s-1900s, mainly used to shuttle freight between railway goods-yards and local businesses.
Among them were many battery-electric, private cars, too; and those were allowed on the roads in London's Royal Parks from which these new-fangled, noisy, smelly, petroleum-spirit fueled equivalents were barred!
Trains. Yes, at least for passenger-trains. It takes far less power to accelerate a given load from rest to a set speed, and maintain that speed, on rails than on roads; and experiments with battery-electric traction are under way.
The world's first public-carrying trials of such started recently on a short line in the London suburbs.
Since Diesel multiple-unit trains with the engines under the coach floors are already commonplace, I see no reason against battery-electric equivalents replacing the DMU for inter-city and suburban routes.
Whether a BEMU carrying, say, 200 passengers would manage the Nullarbor Straight on a single charge, at night with the coach lights and heaters on, remains to be seen! (Steam locomotives had to stop for water part-way, so why not a recharging stop?)
Aircraft: There are already experiments, mainly in Sweden I think, on electrically-powered aeroplanes of limited capacity for short flights. No-one proposes such for intercontinental flight; but the real question there is need for so many flights in the first place.
Ships: Not batteries but fuel-cells perhaps. A large ship requires enormous power to push it through the water, and so far, using batteries for vessels is limited to slow-moving leisure and tourist craft on inland waterways.




