Electric cars

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  1. #1401
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    By making hydrogen batteries interchangeable with lithium batteries according to this organisation: HYDROGEN OFFICIAL FUEL CELL UNIVERSAL BATTERIES
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    Interesting article, Logically, the governments should legislate for a set of standard battery pack formats/connections. Its got enormous benefits for the end consumer from a cost and support perspective.

    In addition, as EVs overtake IC vehicles in numbers, there will be thousands of battery failures, and fuel cells and batteries only have a finite life. Meaning that there will be millions of vehicles requiring servicing, where at the moment that would mean dealing with hundreds of different energy pack formats. Complicating the heck out of EV infrastructure sustainability and challenging the ultimate goal, being the creation of a circular economy. Competitive stakeholders (OEMs, OESs) are unlikely to want to cooperate, it will probably need additional legislation to make them even consider changing their ways.

  3. #1403
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    Manufacturers could follow the ICE historical standardisation process, given the 100 years the industry has had to sort out standard engines, spark plugs, gearboxes, fuels, etc, to make them all interchangeable (sarcasm).
    Before you speak, ask yourself: Is it necessary, it is true, does it improve on the silence? - Baba

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    Yes, biggest bug bear. Want an oil or fuel filter, which one of a 100 types, sizes do you require. Surely as an industry they could have agreed on ~6 types ranging from small to large. I'd hate the EV's to go down the same path as most other battery operated equipment with thousands of pack variations to essentially accommodate the same cells inside.

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    I bought a 3 year old 30 kWh battery Leaf at auction in Japan for $12,000 with 30,000km and battery state of health at 85%. It cost another $8,000 for freight, compliance, customs, GST, etc. I've driven 35,000km and the battery state of health is now 80%. Once the SOH gets down to 75%, the range will slowly begin to reduce, and that will eventually make the car impractical for me given my remote location. So I expect to drive it for another few years and then import a 40kW battery from a wreck (all of the Nissan batteries are physically interchangeable). The extra 25% of capacity of the 40kWh will make it more convenient and at the same time improve the ageing characteristic of the battery. Then I'll sell my old battery to the owner of an old 24kW Leaf who needs a battery and who will in all practical terms be getting a new battery will full range for that model.

    Now that I know a bit more about battery issues, I would only buy a used car/battery with +95% SOH. The condition of every individual one of the 96 cells in the Leaf's propulsion battery is available through the OBD2 port. When an individual cell fails in a battery pack, it is possible to replace that a cell with cell of matching SOH to the battery to restore the battery. That is commonly done in New Zealand where Leafs are quite popular. Wrecks are a popular source for good individual cell packs.

    The total lifetime number of kilometres you get out of a battery depends on both the battery capacity and the way it is used. Unfortunately the car I bought had only every had fast charges (daily in fact) and that is why the battery SOH had dropped to 85% in the first 30,000km. I almost always charge at home, not at fast charging stations, hence the slowing of battery ageing since I got the car.

    I understand that new Nissan Leafs have an 8 year 120,000km guarantee on the battery; if the battery SOH drops below 70% it will be replaced under warranty. There has been a trickle of batteries replaced by Nissan under warranty in Australia. There are old 24kWh battery Nissan Leafs from ~2011 still on the original battery with over 200,000km on the clock.

    Only around two thirds of the capacity of the battery is initially used, so there is no impact on range until the SOH has dropped to <70%. When Tesla gave owners a range boost to escape California fires by an over the air firmware update, all they were doing is allowing the car battery to be more deeply discharged, but still nowhere near to completely empty.

    Owning a BEV is not an ALL or NOTHING situation. Most households have at least two vehicles and usually they are not exactly the same. I have both corded 240 volt tools and rechargeable battery tools. It's usually pretty obvious which tool is appropriate for a given job. As rechargeable tools have got better over the years, the corded tools are getting left more often on the shelf. When I go bush I take the diesel 4WD, not the BEV city car. I would love to have a BEV off-roader but I can't see that being practical anytime soon. I've needed to arrange for fuel dumps in remote locations but there isn't a way I know of to drop off a 44 of electrons.
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  6. #1406
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    Default Electric cars

    A few things tweak my interest with EV’s

    First one is they are very quiet, does this create issues in car parks etc where pedestrians are moving between cars?

    I have never driven an EV but I have driven old electric forklifts and the torque was amazing. I am guessing this is basically a given for any EV independent of the cost or model.


    The risk of batteries catching fire is the only real concern I have especially in a crash but is this valid concern or just feat of the unknown?


    o

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    I haven't run over any pedestrians yet, but sure, some people are caught unawares of your presence. As I posted above here #1387 in reality ICE cars are about ten times more likely to end up in a fireball thanks to liquid fuel igniting so easily in the presence of sparks.
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    Default Electric cars

    Thanks John

    If you are unaware of pedestrian issues is is not likely to be an issue. I often wonder what the world would sound like without the hum of the the ICE we will find out soon.

    I am not sure of the statistics given on ice verse ev’s in regard to fires as EV’s are on average much younger and don’t have issues with ageing wires.


    ro

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    Quote Originally Posted by Forrestmount View Post
    ... I often wonder what the world would sound like without the hum of the the ICE
    ...
    You should have been in Melbourne during Stage 4 lockdown

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    Quote Originally Posted by Forrestmount View Post
    I am not sure of the statistics given on ice verse ev’s in regard to fires as EV’s are on average much younger and don’t have issues with ageing wires.
    Batteries are not really that flammable. Have you heard of house fires caused by laptops or mobile phones? In fact, who would dare put a phone in their pocket given the risk of lithium battery fires?
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    Default Electric cars

    Quote Originally Posted by John2b View Post
    Batteries are not really that flammable. Have you heard of house fires caused by laptops or mobile phones? In fact, who would dare put a phone in their pocket given the risk of lithium battery fires?
    Great response

    We have a special charging area at work for recharging as we have had fires in the past. But I don’t know if these fires were the charger or the batteries. I did draw conclusions as the fires occurred at the same time as the airline announced a crackdown on battery packs. But this was an assumption based on coincidence only.

    It is entirely likely they are as safe as you say John )


    PaT

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    Quote Originally Posted by John2b View Post
    Batteries are not really that flammable. Have you heard of ... fires caused by laptops ...? ...
    Yes. In recent past deployments of laptops, staff of a certain major Australian company had been advised not to transport their laptops in Sleep mode due to fires in company cars. This was in the lithium battery era. Rare, and the requirement was likely highly precautionary, but it has happened

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    Quote Originally Posted by r3nov8or View Post
    Rare ... but it has happened
    Sure, and why souvenir book matches were banned years ago. Of course Australian companies were happy for everyone to take jerrycans of petrol with them in company cars in the fossil energy era, not! And why gas cigarette lighters have been banned on flights for decades, not that anyone took any notice of the ban.
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    Quote Originally Posted by John2b View Post
    Sure, and why souvenir book matches were banned years ago. Of course Australian companies were happy for everyone to take jerrycans of petrol with them in company cars in the fossil energy era, not! And why gas cigarette lighters have been banned on flights for decades, not that anyone took any notice of the ban.
    Why so bitter and twisted? Sheesh!

  15. #1415
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    "Huawei has launched its first car, marketed as part of a collaboration with auto brand Seres – offering more than 1000km of range and a sub-five-second 0-100km/h time."

    https://www.caradvice.com.au/946470/...021-seres-sf5/

  16. #1416
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    Quote Originally Posted by r3nov8or View Post
    Why so bitter and twisted? Sheesh!
    Just saying things like they are. Perhaps being an 'idiot' subject of this thread doesn't help; by all means amuse yourself by reading from the start.
    Before you speak, ask yourself: Is it necessary, it is true, does it improve on the silence? - Baba

  17. #1417
    4K Club Member Marc's Avatar
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    Why do people buy electric cars?
    "Because they are idiots" would be my comment, but no, let's be honest, they deep down believe that they have a moral obligation towards "the environment".
    So they ignore and look the other way of the hundreds of components that pollute the many other countries that manufacture them, ignore the price tag that makes it an impossible proposition, ignore it's enormous limitations and trade ins, and then ... they run out of juice.
    Not to worry, there is always the generator.



    This was my tongue in cheek opening post, and I stand by it.

    The problem with any debate that involves so called renewables, electric cars and environmental issues, is that they are not technical discussions... (edited out: climate trolling)

    If you want to have a debate about excavators, different sizes, attachment, brands, and the latest wave of crap chinese knock offs, you have a technical discussion. I am a Takeuchi man, best excavator on the planet.
    Can you have a similar debate on electric cars?


    With such a background, discussions are far from technical and slip way too easily in the electric vs petrol and how the bad capitalists have had 100 years and the poor electric beggar is just starting to pollute just now etc etc etc.
    Let's face it, as much as electric cars are interesting animals and will inevitably rise in numbers, they exist due to commercial and political interest, not to make the planet a better place. So any allusion to the real or imaginary sins of the petrol or (god forbid) diesel vehicles and their evil manufacturers and marketeers, is pure political garbage.

    But I concede that deep down, if you look and scrutinise with a powerful magnifying glass and LED torch, you can probably find someone who is interested in them purely for technical and financial reasons, if his peculiar location and activity makes him the exception to the vast majority.
    You never know.
    For me it is Takeuchi all the way.

    Last edited by phild01; 24th Apr 2021 at 10:59 AM. Reason: climate trolling
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  18. #1418
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    The manufacture of any vehicle uses resources. There's nothing that makes BEV cars worse than ICE cars when you take 'the whole of life' resource use into consideration.

    The irony off the picture of the BMW being charged by a generator is that the BMW will make more efficient use of the fuel consumed by the generator than an ICE vehicle using the fuel, because an ICE vehicle's engine is almost never running anywhere near the ideal load and revs for efficient energy conversion.

    That's one reason why diesel-electric is the dominant locomotive design, the other being the elimination of a gearbox and having full torque at zero revs, also a big advantage for the drivability of electric road vehicles.
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    Hydrogen turbine/ electric will be the dominant technology for heavy transport in the future. Well it will be if we decide to be smart
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  20. #1420
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    Rubbish.
    The petrol used in that piffy generator would go a long way to outstrip any of the many inefficiency of that system if in a modern petrol car, and not converted to electricity with huge losses and then stored in batteries with more losses only to turn into motion with yet again more losses
    And locomotives have diesel generators and electric motors simply because there is no way to make that size gearbox in an acceptable weight. Locomotives diesel engines don't run a generator to charge batteries, they run multiple electric motors directly connected and the load on the diesel is variable according to speed and load of the train they are pulling, like any other diesel engine pulling a load. The combustion in a diesel locomotive is as efficient and as inefficient as it is in a truck or a boat. You only need to watch them take off and see the plume of black soot at take off and listen to the acceleration required to get the ac or dc motors going.
    Once they are at constant speed, the engine combustion is near optimal, not because of the generator, in fact there are substantial losses there too, but because they are usually in rural settings running long distances, just like a truck or a ship.
    For a disel-electric system to work in a start and stop situation like urban train, there would be the need for a third element, batteries, introducing yet another source of losses.
    But since you are an engineer, I am sure you are aware of this.
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    Marc, I have always understood the gen sets in diesel electric make more efficient energy conversion than a a diesel only locomotive.

  22. #1422
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    Yes and no. To begin, diesel only locomotive are a rarity and always on the small side, so hard to compare.

    If diesel electric is more efficient than diesel only, why don't all trucks and busses use it? Why not all cars?
    The answer is not simple. To get the energy transformed by the diesel engine into the wheels for motion, one can use mechanical gearboxes or electric motors powered by a generator. Both incur heavy losses.
    But the scale is the key. Diesel electric is more efficient in large scale, mechanical or hydraulic is more efficient in relatively smaller scale.

    To say that diesel electric is more efficient, implies that it is more efficient because of the use of electric motors, yet that is not true. It is more efficient simply because as the scale increases, the losses from mechanical gearboxes increase exponentially. Somewhere above 1000 HP, diesel electric is more practical

    However the reason outlined by John that diesel electric is more efficient because the diesel engine works at an optimal ratio and converts fuel into energy more efficiently is disingenuous, because unless the diesel engine is charging batteries and running always at the same speed, the normal diesel electric that does not have a battery bank, has to accelerate like any other truck or bus does. The only difference is the way it transmit energy to the wheels.

    The way an electric motor can produce full torque at zero revs, makes it ideal for a diesel engine that has a limited range of 300 to 900 revs, and that would need dozens of gears, to apply full torque to the wheels at different speeds.

    Both the gearbox and the generator/electric motor, are energy pits, and each has its applications. And their range of application do not overlap.
    https://youtu.be/nxfb78LcWto?t=104
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    Quote Originally Posted by Marc View Post
    But since you are an engineer, I am sure you are aware of this.
    Yes Marc, I started a Bachelors Degree in Electrical Engineering, later changing to Electronic Engineering, and that is why I know my post is correct. I finally specialised in Electro-acoustic Engineering in which field I have been an Australia-wide consultant, but all engineering is based on the same laws of physics, the most notable being the law of conservation of energy which applies directly to energy transformations, such as motion to chemical energy in liquid fuel or electricity stored in batteries.

    There is 39MJ of energy stored in a litre of petrol or diesel that is released in reciprocating engine. 39Mj is the same amount of energy as 10.8kWh. An electric car like my Nissan Leaf gets 8 km/kWh, equivalent to better than 85kpl of energy equivalent liquid fuel. When I run my Honda generator (for which the engine is tuned and runs at maximum energy conversion efficiency) it uses 3.1 litres of fuel to produce 5 kWh of electricity, enough for the Leaf to cover 40 kilometres. Even after allowing 15% loss for the charger and motor controller, it gets better milage than a typical car would if it burnt the fuel my generator used.

    Look at the losses in an ICE vehicle: around 88% of the energy fed into the engine is lost as heat in the radiator and exhaust, noise, valve train, pumping losses, generator, ancillary pumps, torque converter, transmission, etc. It's no wonder a petrol or diesel car gets around 1km/kWh of energy compared to an electric car getting 8km/kWh, or that the petrol/electric Toyota Prius, which runs its ICE at optimum load to charge a small battery that runs the electric propulsion motor, gets better than 25kpl.
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    Quote Originally Posted by phild01 View Post
    Marc, I have always understood the gen sets in diesel electric make more efficient energy conversion than a a diesel only locomotive.
    This quote from a former engineer at GM's Electro Motive Division puts it better than I can:
    Mechanical transmissions cannot match the efficiency of the best electrical transmissions. Except when (a mechanical transmission is) direct coupled and operating at the ideal engine speed with no slippage through the transmission, the diesel electric is more efficient, because it allows the diesel to operate at the most efficient speed for a particular horsepower output, instead of the speed determined by the transmission and the speed of the train (rotation of the wheels). Using the gen-set approach, a diesel electric is even more efficient, since only enough engines to supply the needed horsepower need operate at a particular time.
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    Where's the Atomic batteries promised by all the Science Fiction writers of the 1950s?
    An EV with an unlimited range.
    "A big boy did it and ran away"

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  26. #1426
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    I started a Bachelor's Degree in Electrical Engineering, later changing to Electronic Engineering, and that is why I know my post is correct.
    I am happy for you that you finished your degree, yet such does not make you right. Clearly you are having a bad hair day

    This is the situation: We have two cars: one is the "stupid" electric BMW stranded with no charge ... and we will introduce a Toyota Corolla for comparison.
    Both will require the same energy to travel the same distance if they are of equivalent weight.

    We give each car 5 litres of petrol. One will go straight into the Toyota Corolla that is new and ready to go. Efficiency 30%.

    The other 5L will go into a little screamer Briggs and Stratton that needs to churn a third class generator (efficiency 13%) , push electricity through long cables, charge batteries (charge 80% discharge 90%)and finally end in the electric motor. (88% efficiency)

    In your parallel universe, the energy stored in the 5l of petrol that goes in the generator, actually give more energy than the petrol going into the corolla, despite the cascading losses starting with a petrol motor that is clearly less efficient than the corolla, followed by a string of other losses.
    Fanciful, but the first law of thermodynamics applies even in that particular universe.
    Of course if you can dominate the skill of teleportation, things may go differently. Until then, I am afraid you are wrong. Engineer degree or not.

    As for the diesel electric system used in locomotives, I would be happy to answer if you actually read my post and answer it's points directly without evasions or quotes.
    You are wrong on that account as well. Diesel electric systems with no batteries, vary the power output by opening up the fuel injection or reducing it, the diesel engine varies the revs up and down with the corresponding variations in efficiency. The rest is nonsense or is talking about a different system and not a diesel electric locomotive.

    For whoever is interested, this is how a diesel electric locomotive works.
    https://science.howstuffworks.com/tr...locomotive.htm
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    Nothing beats the smell and sounds of walking through a running shed at a steam locomotive depot.

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    Good alternators should be about 75 to 80% efficient and to quote your own link the diesel engine runs at a constant speed Marc
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    Quote Originally Posted by Marc View Post
    We give each car 5 litres of petrol.
    The problem with your statement is that you have the efficiencies the wrong way around. An ICE engine propelling a passenger vehicle will struggle to convert 15% of the liquid fuel consumed into energy used for propulsion. There are lots of reasons for this, the main one being that the engine is rarely, if ever, at optimum speed and load for efficiency of energy conversion for very long. It also has many parasitic loads and needs to burn fuel even when idling, coasting and braking. Contrast that with a BEV electric motor that does not have parasitic loads, nor use energy to idle or coast, and actually recovers energy into the battery when braking.

    Compare the circumstances of an engine in a vehicle with the ' little screamer ' engine, which is in fact running continuously at, or very near, peak Otto cycle efficiency, and not losing energy into a heap of parasitic loads - there is no auxiliary generator, water pump, oil pump, etc, etc attached, just the alternator load. The alternator driven by the ' little screamer ' would be very primitive if it didn't have an efficiency above 95%, even a very basic cheapie is highly efficient, so the total efficiency of even a basic petrol genset will be around 25% or more.

    The charge/discharge efficiency of lithium batteries of the type used in cars is ~98-99%, not the 72% (80% x 90%) you quote, and the efficiency of the traction controller/motor is typically in the 92 - 95% range, and sometimes higher.

    The Nissan Leaf is at the bottom of the pile of BEVs when it comes to efficiency yet it is still at least on par with a similar ICE vehicle for fuel efficiency when charged from a basic petrol generator. I know this I have actually done it a couple of times. I know how many kilometres of range I get from the 6 litre fuel tank on my genset. If you have charged an electric car from a petrol or diesel generator and have different data, please post it.
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    What nonsense, where do you guys get your facts?

    This magic "constant speed" is supposed to make a B&S more efficient than a fuel injected new Toyota? Are you kidding? And just in case someone missed this, both cars are of the same size and must travel the same distance, so they will use the exact same amount of energy.
    The source of energy for both cars comes from the same amount of fuel. One is converted by a modern fuel injected engine, the other by a splattering carbureted little toy engine, that has to pass it's litle excuse of a work, to generator and batteries and electric motor ... come ooooon!

    Regardless ... your engineer instinct should have kicked in way before you typed this and the previous post.
    We are comparing an ICE in ordinary circumstances with a system composed from a ICE, coupled to a generator connected with long cables to a battery that in turn will power an electric motor. If you want me to believe the latter is more efficient than the former, because "the B&S runs at constant speed," you have something else coming.

    Even if we disregard all the multiple and severe losses in the system after the generaotr, clearly the toyota engine is more efficient than the B&S and so your assumption is wrong from the start.

    As for the locomotive:
    The throttle control has eight positions, plus an idle position. Each of the throttle positions is called a "notch." Notch 1 is the slowest speed, and notch 8 is the highest speed. To get the train moving, the engineer releases the brakes and puts the throttle into notch 1.
    In this General Motors EMD 710 series engine, putting the throttle into notch 1 engages a set of contactors (giant electrical relays). These contactors hook the main generator to the traction motors. Each notch engages a different combination of contactors, producing a different voltage. Some combinations of contactors put certain parts of the generator winding into a series configuration that results in a higher voltage. Others put certain parts in parallel, resulting in a lower voltage. The traction motors produce more power at higher voltages.
    As the contactors engage, the computerized engine controls adjust the fuel injectors to start producing more engine power.
    The brake control varies the air pressure in the brake cylinders to apply pressure to the brake shoes. At the same time, it blends in the dynamic braking, using the motors to slow the train down as well

    Above is a brief description of how the train accelerates or decelerates. The generator in a locomotive is not like your town generator that runs at 50 hz regardless because it is subject to relatively constant load. The locomotive has a huge variation in the load and this reflects in the throttle that the conductor needs to change when wants to go faster or slower. The generator can run at various speeds as opposed to the town generator that needs to stay at constant speed to put out constant voltage.
    The magic "constant speed" when desirable for efficiency, is bogus in this case and the reality is that diesel engines in locomotives are efficient due to size design and the fact that the revolution range is small, from 250 idle and 900 max.
    The way the power of the diesel engine is transferred to the wheels is not the reason for its efficiency, it just happens to be the most feasible way to do it. A much better way would be like in large bulk carriers that have the shaft of the engine directly linked to the shaft of the ship and that need to stop the engine and start in reverse to stop. Not very practical for a train but more efficient because it eliminates the losses from generator and motor. Losses not gains.
    The diesel electric locomotive is a large 3 to 4000HP diesel engine, some 2 stroke some 4 stroke that drives the train. The diese lengine needs to go through different ratio to get the train moving and rise the speed to the top speed. Once at cruising speed, the driver will try to keep the revs at the most efficient revs, but can push it higher or keep it lower according to need, just like in a ship. No "constant speed" to be seen anywhere.
    There are boats and small ships that run diesel engine generators to charge battery banks that drive electric motors to move the ship. They are expensive contraptions that allegedly are more efficient due to the magic constant load on the diesel generator. Are they more efficient? Depend who you ask. If you ask the owner who has to pay for the battery bank replacement, you will get a resounding no. (They do try to mask the bullmanure by having solar panels and sails and mandating that the crew farts always pointing at the stern. )
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  31. #1431
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    Quote Originally Posted by Marc View Post
    And just in case someone missed this, both cars are of the same size and must travel the same distance, so they will use the exact same amount of energy.
    In the real world a vehicles start and stop for intersections and traffic lights, etc. Under many conditions the ICE continues to consume energy when the BEV does not. To slow an ICE vehicle brakes convert kinetic energy into waste heat in the brake disks which is lost to the environment. When a BEV brakes, most of the kinetic energy is converted back into electricity used to recharge the energy stored in the battery. So the notion that the two types of vehicle use the same amount of energy supplied to the vehicleto cover the same distance is patently incorrect.

    Computer engine management has dramatically improved internal combustion engine conversion efficiency under light loads and non-ideal rpms, however the peak efficiency of the Otto cycle in an ICE is set by physics, not whether a motor has fuel injection.
    Before you speak, ask yourself: Is it necessary, it is true, does it improve on the silence? - Baba

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    You said that the petrol used in the generator charging the BMW would make the electric car go further than the same petrol used in a similar ICE car. That is without a question potentially false. If you now want to introduce traffic lights and the driver that misess an intersection and stops to go to the loo, well, very funny I suppose.
    If you want to debate petrol engines that are carbureted vs injected, be my guest.

    Every petrol or diesel engine has a particular load and engine revs combination that is ideal for said engine. Most drivers with minimal experience know what speed their car is more fuel efficient. If you depart from that either up or down, fuel consumption increases.
    The statement that diesel electric is more efficient due to constant revs, is also intrinsically false, because the diesel engine in a locomotive goes through constant changes in revs, to adjust current output and match the load. A diesel locomotive will struggle up a hill and open up fuel injection not to lose ground, resulting in a much higher fuel burn just to catch up. That is how engines work, and under peak load, any engine is less efficient. At cruise speed and ideal conditions all engines, petrol or diesel, manual gearbox, automatic or electric transmission, have a sweet spot where they excel. It has nothing to do with the type of transmission.

    An industrial or domestic generator, is set to work at constant speed purely because it needs to produce constant voltage as opposed to the locomotive that works with a range of voltage. The generator controller set at 50 hz when subject to higher loads, will open up the fuel intake and reduce when the load drops. Does it mean that constant speed/revs makes it more efficient? No, it will be more efficient at a certain range and load that depends of the engine and generator build. pass the ideal capacity and you waste fuel, run ad low load and waste more fuel. Just like any other engine.
    Whenever you find yourself on the side of the majority, it is time to pause and reflect
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    Quote Originally Posted by Moondog55 View Post
    Where's the Atomic batteries promised by all the Science Fiction writers of the 1950s?
    An EV with an unlimited range.
    Nuclear powered “batteries” have existed for many decades. Not super large I grant you but they do exist. I started work as an apprentice at Westland Helicopters in 1964 and after six months in the apprentice school and three months on the production line got transferred to Saunders Roe for six months. Saunders Roe was “owned” by Westland Helicopters and had a production facility co-located with Westland Helicopters producing Betalights. My job was to design and build laboratory equipment.


    https://www.betalight.nl/home/history.html
    “What a fool believes, he sees. No wise man has the power to reason away”- The Doobie Brothers

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    An engine has one revolution rate at which the energy conversion is most efficient. It is often the RPM near or slightly above the peak torque RPM. If the engine is producing a fixed output, say 50% of its rated output, it can also produce that output at higher or lower RPM than the most efficient - at the penalty of energy conversion efficiency!

    Likewise an engine has a load which at the most efficient RPM that will result in the maximum conversion of fuel energy into kinetic energy, usually near 100% of its rated output. The engine can produce less power at this most efficient RPM, but again at the penalty of energy conversion efficiency.

    A properly designed small generator (i.e. an engine who's output is matched the the load presented by the generator) is operating at both its maximum efficiency RPM and at its maximum efficiency load. Under those conditions the addition of a sophisticate fuel injection system doesn't add much to efficiency, because even a simple carburettor that is designed specifically for one set of conditions can be made to work quite well.

    Of course the previous sentence does not apply to variable speed, variable load engines, like a gensets used intermittently on a building site, for example. Nor does it apply to ICE vehicles where the engine is running at variable speeds and variable loads. There are huge gains using sophisticated engine management systems for variable speed, variable load engines. But friction losses in the engine still dominate energy consumption at low engine loads like idling, coasting and cruising, plus all of the ancillary loads that an ICE needs in a vehicle in order to operate consume proportionally more energy at low loads. That is why an ICE in a passenger vehicle will struggle to achieve 15% conversion efficiency of liquid fuel into kinetic energy in real world on-road use.

    Large diesel electric locomotives often have two, three or four diesel engines so that in cruise one or more engines can be turned off, and the remaining engine(s) loaded for greater efficiency. Of course the main benefit of the diesel electric transmission is to completely decouple engine RPM from wheel RPM, using AC inverter technology. The frequency of the generator, which is locked to the engine rpm, is converted by an inverter to the frequency the electric motors need to match the RPM the wheels are turning at; then the Diesel engine, the generator and the electric motors are all able to operate at peak efficiency. This is similar to the principle of inverter technology used in air conditioners and microwaves to maximise energy conversion efficiency.
    Before you speak, ask yourself: Is it necessary, it is true, does it improve on the silence? - Baba

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    Mm ... yes ... therefore ... ?
    Whenever you find yourself on the side of the majority, it is time to pause and reflect
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    Tesla - China honeymoon is over.
    https://youtu.be/5RiZf6t4nG4
    Whenever you find yourself on the side of the majority, it is time to pause and reflect
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    Quote Originally Posted by Marc View Post
    Tesla - China honeymoon is over.
    https://youtu.be/5RiZf6t4nG4
    No surprises

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    What is surprising how seemingly intelligent company CEO keep on making the same mistakes, and assume they will be the exception.
    Whenever you find yourself on the side of the majority, it is time to pause and reflect
    Mark Twain

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    I don't agree with all of the sentiments in this video; consider it 'balance' to Marc's video linked above. It does contain some truths that our guvmint's can't or won't swallow, and where their policies or lack of them runs contrary to the views of between 70% and 80% of the electorate Australia wide. And no need to set aside an afternoon to watch it, the clip is only a couple of minutes long!

    https://youtu.be/fLflYkgnNBY
    Before you speak, ask yourself: Is it necessary, it is true, does it improve on the silence? - Baba

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    What a load of merda
    Whenever you find yourself on the side of the majority, it is time to pause and reflect
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    Lol
    “What a fool believes, he sees. No wise man has the power to reason away”- The Doobie Brothers

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    Quote Originally Posted by John2b View Post
    I don't agree with all of the sentiments in this video; consider it 'balance' to Marc's video linked above. It does contain some truths that our guvmint's can't or won't swallow, and where their policies or lack of them runs contrary to the views of between 70% and 80% of the electorate Australia wide. And no need to set aside an afternoon to watch it, the clip is only a couple of minutes long!

    https://youtu.be/fLflYkgnNBY
    Plagarising UseByDate post?

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    Quote Originally Posted by Bros View Post
    Plagarising UseByDate post?
    Oops - missed that! So it seems did Marc.
    Before you speak, ask yourself: Is it necessary, it is true, does it improve on the silence? - Baba

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    Beautiful sound of the 2 stroke Detroit Diesel in a diesel electric locomotive and it's vastly variable load and revs.
    https://youtu.be/ciJqIxLdjyQ
    Whenever you find yourself on the side of the majority, it is time to pause and reflect
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    Victorian government plans to dramatically boost the sale of electric cars by 2030

    https://www.abc.net.au/news/2021-05-...cars/100108626

    Mr Clutterbuck wanted to do his bit to save the planet by buying an electric car.(ABC News: Richard Willingham)
    Good for you Mister Clutterbuck, but,


    Posted by
    John2b
    , And no, BEVs are not going to save the planet, which doesn't need saving anyway.
    Posted by John2b, And no, BEVs are not going to save the planet, which doesn't need saving anyway.

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    Quote Originally Posted by Bedford View Post
    Good for you Mister Clutterbuck, but,
    As best as I can reckon the point of no return for maintaining an environment conducive to human civilisation for the next few generations was around 1980, maybe earlier. Planet Earth will see the back of the human race, electric cars or not, and continue on around the sun for a few more billion years, probably not even slightly affected by the absence of the current human plague.

    Elon Musk will be being driven around Mars by his autopilot electric car long before then, so it's worth Tesla keeping BEV development going for the time being, but I'll keep not buying Tesla shares. For now I will keep driving my electric car simply because it costs less for me to own and is a superior car than an equivalent ICE car.
    And quite likely people who don't own a BEV will continue to 'know' how bad they are.
    Before you speak, ask yourself: Is it necessary, it is true, does it improve on the silence? - Baba

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    Quote Originally Posted by John2b View Post
    ... For now I will keep driving my electric car simply because it costs less for me to own and is a superior car than an equivalent ICE car.
    ...
    Whaaaaat!!? Superior car? What makes a new Nissan Leaf, costing $53k-$65k, superior to just about any other new car in that price range? Performance? Comfort? Range? Driving dynamics? Carrying capacity? Towing capacity? No. But it does have a battery and is bloody ugly.

    screenshot_20210501-221525_carsales.jpg

    Ahhh Wait! I know! It's quiet. That must be it!

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    Quote Originally Posted by r3nov8or View Post
    Whaaaaat!!? Superior car? What makes a Nissan Leaf, costing $53k-$65k, superior to just about any other new car in that price range? Performance? Comfort? Range? Driving dynamics? Carrying capacity? Towing capacity? No. But it does have a battery and is bloody ugly.

    Ahhh Wait! I know! It's quiet. That must be it!
    Consider that John bought his Leaf for a fraction of the new price and can drive comfortably because he lives on an island, and recharges at home or I believe the shopping center for a pittance. I would be talking up my electric car too in such circumstances.

    What needs considering in the electric car market, is the unashamed profiteering by manufacturers and sellers leaning on governments to boost their outrageously overpriced contraptions, with pretenses of (non existing) environmental advantages. It is one more collusion between governments and industry the likes we have seen repeatedly in the last 100 years or more. Nothing to see here.

    "The future" as we all know, is immersed in the fog of change, and those so eager to predict it may or may not fall on their faces. The driver as it is the case once more, for the supporters, advocates and assorted cheerleaders, is not experience, knowledge or scientific acumen, but ideology, preconception and bias, mounted on hidden agendas and foreign interest.

    In the past it was the steam engine first, and then the diesel engine to drive industry. Diesel is still driving the industry today and it is only behind nuclear energy that, ironically, is just the heat to drive steam turbines, so not too far from the modest beginnings. Learning how to produce steam from a volcano would probably be more intelligent than using nuclear crap.

    COnsidering that the electric motor is just the last cog in the machine and that it is completely dependant from the power plants that drive them, to consider electric cars a fundamental and landmark change, is rather absurd. The electric washing machine has probably had more impact than the electric car will.

    New sources of energy is what will mean a real landmark in human history like steam and diesel was.
    I wait for such news with eagerness.
    And screw Tesla and the rest of the electric contraptions.

    PS
    Still awaiting for the cars that were supposed to fly in the year 2000 ...
    https://io9.gizmodo.com/how-our-pred...oughou-5908600
    Whenever you find yourself on the side of the majority, it is time to pause and reflect
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    Isn't Geothermal heat driving steam turbines big in places like New Zealand and Iceland???
    "A big boy did it and ran away"

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