Enthalpic + 1,496 June 16, 2020 (edited) 20 minutes ago, Dan Clemmensen said: Those are DC "super chargers", which really do go up to 250 kW. The two DC conductors in the charging cable are really big, and the DC voltage in that cable is 480 V. I have no idea what is behind that plug inside the supercharger, but I very much doubt it's a 240 VAC input. See https://en.wikipedia.org/wiki/Tesla_Supercharger Very few types of EV have the internal busses required to actually draw 150 kW. New Teslas can do it. There is no way that Germany can mandate a DC super charger for every petrol station. They have probably mandated a SAE 1772 level 2 charger. Wow. Mandate, maybe not, but if the stations can make money market forces might get them installed. Get enough people leaving their cars for too long and you could make good money off parking spaces ($0.50 - $1.00/ minute). Just have one station and it's 100% full with only one car! hehe. "Fees for remaining connected after being fully charged Since December 16, 2016, any car that remains connected to a Supercharger after being fully charged may be fined. In the United States, there is no fine if the Supercharger station is less than half full, a fine of $0.50 per minute if the station is at least 50% full, and a fine of $1.00 per minute when the station is 100% full (these fees may vary by country).[60] This fee is waived if the car is removed in five minutes. Any incurred fees must be paid by the time of the next service visit.[61]" https://en.wikipedia.org/wiki/Tesla_Supercharger#Fees_for_using_Superchargers Edited June 16, 2020 by Enthalpic 1 Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 16, 2020 (edited) 23 hours ago, footeab@yahoo.com said: 🤣😂 What are you? A dinosaur from the 1940's? Holy Shit... Hell, relay computers from the 1950's are more than enough for this VERY simple amperage, voltage, capacity, temperature, cycles slope curve hard wired into memory. The "computer" on your microwave is more than powerful enough to operate said charger. If you want to hit the "BIG TIME", then a hand calculator from 1985 can do it. OK, I think I figured it out. The car might be "smart" enough to connect to a 250 kW 480 VDC circuit, but if it's a Tesla, it does not have the internal circuitry to current-limit the DC voltage: such circuitry would be expensive and heavy. The DC input contacts in the cable are directly connected to the car's DC battery bus! Tesla is apparently arrogant enough to believe this is safe, but only if they are certain they have control of both ends of the connection. The super charger must already have a AC-to-DC convertor with large controllable rectifiers, so the station can rate-limit with no additional high-power equipment. Sure, you could create an open-standard protocol to allow the car's computer to control the station, but a screw-up that caused a fire would have "consequences". By contrast, a SAE 1772 connection depends on the car to control the AC current, and the AC is converted to DC in an converter inside the car. The spec maxes out at 22 kW. The charger is very, very dumb. If the car catches on fire, it's not the charger's fault. If the charger catches on fire, it's not the car's fault. The charger provides basically one signal to the car: an analog sine wave whose frequency tells teh car the max amperage the charger will provide. If the car tries to pull more current, the charger uses the highly sophisticated technique of blowing its circuit breaker. Edited June 16, 2020 by Dan Clemmensen spelling 1 Quote Share this post Link to post Share on other sites
footeab@yahoo.com + 2,190 June 16, 2020 13 minutes ago, Dan Clemmensen said: OK, I think I figured it out. The car might be "smart" enough to connect to a 250 kW 480 VDC circuit, but if it's a Tesla, it does not have the internal circuitry to current-limit the DC voltage: such circuitry would be expensive and heavy. The DC input contacts in the cable are directly connected to the car's DC battery bus! Tesla is apparently arrogant enough to believe this is safe, but only if they are certain they have control of both ends of the connection. The super charger must already have a AC-to-DC convertor with large controllable rectifiers, so the station can rate-limit with no additional high-power equipment. Sure, you could create an open-standard protocol to allow the car's computer to control the station, but a screw-up that caused a fire would have "consequences". By contrast, a SAE 1772 connection depends on They aren't using rectifiers in AC to DC conversion, could but is inefficient. 🙄 And yes, tying directly to your battery bus is perfectly safe... The ONLY way to connect to a battery... If you really want to throw in a relay/breaker, in the car, ok. Waste of money, as a drop in signal from the car say should stop the operation immediately for power delivery, but interlocks on both ends are pretty much required anyways in the connector. Can't exactly leave upwards of 600V leads hanging out and about for some kid to stick their pinkies into when they steal mommy's key. All it requires is a very simple data port to said charger station with a [yes, hold, no] toggle at interval of say a millisecond for said amperage delivery and 2 yes's in a row increase amperage faster than a single yes, a single no decreases amperage, double no, decreases faster. There is absolutely no need for the charger to know the car model, battery type etc. The car as a safety check, measures the current/voltage(they already do) this will limit total amperage. If you really want to be safe add a second line on data port which the car and charger compare currents so as to contain problem regarding circuitry drift over time, ok(Calibration comparison seems like a good idea to me). Very simple circuitry required here. Off hand a charger with increments of 10A is perfectly acceptable. 1 Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 17, 2020 5 hours ago, footeab@yahoo.com said: They aren't using rectifiers in AC to DC conversion, could but is inefficient. 🙄 And yes, tying directly to your battery bus is perfectly safe... The ONLY way to connect to a battery... If you really want to throw in a relay/breaker, in the car, ok. Waste of money, as a drop in signal from the car say should stop the operation immediately for power delivery, but interlocks on both ends are pretty much required anyways in the connector. Can't exactly leave upwards of 600V leads hanging out and about for some kid to stick their pinkies into when they steal mommy's key. All it requires is a very simple data port to said charger station with a [yes, hold, no] toggle at interval of say a millisecond for said amperage delivery and 2 yes's in a row increase amperage faster than a single yes, a single no decreases amperage, double no, decreases faster. There is absolutely no need for the charger to know the car model, battery type etc. The car as a safety check, measures the current/voltage(they already do) this will limit total amperage. If you really want to be safe add a second line on data port which the car and charger compare currents so as to contain problem regarding circuitry drift over time, ok(Calibration comparison seems like a good idea to me). Very simple circuitry required here. Off hand a charger with increments of 10A is perfectly acceptable. Pretty much my entire 45-year professional career involved communications protocols. I actually designed, developed, and popularized a protocol named OpenAMIP that became an industry standard in the satellite terminal industry. It's not that hard. In today's world, I estimate that circuitry and incremental software and CPU costs would not exceed five cents in the car and in the charger. It would take a week or two to specify and implement the protocol and a year or two to get it through the standards bodies. Sitting in those meetings is tedious. ARINC decided to use a variant instead of the original OpenAMIP because I had required that any implementor of OpenAMIP had to agree that any other implementor must be allowed to publish a compatibility test report about the performance of any product that implemented the protocol. The ARINC protocol was identical except for the name. 1 Quote Share this post Link to post Share on other sites
BradleyPNW + 282 ES June 17, 2020 9 hours ago, Enthalpic said: 600A at 240V? Is that a typo? Isn't that 140,000+ W? Pretty sure 140,000W would melt your car. Haha The biggest energy hogs at the lab used 50A at 240V and even those cords were damn thick and were wired directly to a breaker (no plug). Probably a typo. Tesla: Quote Share this post Link to post Share on other sites
BradleyPNW + 282 ES June 17, 2020 "Currently available DC fast chargers require inputs of 480+ volts and 100+ amps (50-60 kW) and can produce a full charge for an EV with a 100-mile range battery in slightly more than 30 minutes (178 miles of electric drive per hour of charging). However, new generations of DC fast chargers are gaining traction and can produce 150-350 kW of power."https://calevip.org/electric-vehicle-charging-101#:~:text=Currently available DC fast chargers,drive per hour of charging). Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 17, 2020 12 hours ago, BradleyPNW said: "Currently available DC fast chargers require inputs of 480+ volts and 100+ amps (50-60 kW) and can produce a full charge for an EV with a 100-mile range battery in slightly more than 30 minutes (178 miles of electric drive per hour of charging). However, new generations of DC fast chargers are gaining traction and can produce 150-350 kW of power."https://calevip.org/electric-vehicle-charging-101#:~:text=Currently available DC fast chargers,drive per hour of charging). While the latest chargers can put out up to 350 kW, There is no current EV that I know of that can accept more than 150 kW. 1 1 Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 17, 2020 13 hours ago, BradleyPNW said: "Currently available DC fast chargers require inputs of 480+ volts and 100+ amps (50-60 kW) and can produce a full charge for an EV with a 100-mile range battery in slightly more than 30 minutes (178 miles of electric drive per hour of charging). However, new generations of DC fast chargers are gaining traction and can produce 150-350 kW of power."https://calevip.org/electric-vehicle-charging-101#:~:text=Currently available DC fast chargers,drive per hour of charging). The SAE 1772 level 2 chargers in your earlier table are the ones you can put in almost any house in the US: they go up to 11.5 kW if you can provide a 60 A 240VAC circuit. Most of teh tens of thoudands of older charging stations in the US are also of this type. The enormous DC super chargers you mention in this post go from 150 kW on up, But this is usually between two charging stalls. This works out because one of the two cars is likely finishing up its charge (which requires the power to be reduced) while the other one is starting up its charge at full power. There is a third class of charger, at least in the Tesla universe. These are called "destination chargers" and are installed by businesses and usually reserved for their customers. These are DC chargers with power usually between 50 kW and 75 kW. Not too shabby if you are spending 2 hours shopping. 1 Quote Share this post Link to post Share on other sites
footeab@yahoo.com + 2,190 June 17, 2020 14 hours ago, BradleyPNW said: Probably a typo. Tesla: Nope: 600 Amps is just fine... of course no one will install it as the cables required to carry 600amps are 3cm in diameter before we add insulation which means actual diameter will be ~4cm or greater... This is not an exaggeration. Solid cables that size will require overhead crane to move them for granny/grandad and small women. The only way true fast charging happens is if much higher voltage becomes normal. Of course this means semi exotic insulation and rigid conductors as your plastics breakdown over 1000V. Yea yea, officially PVC etc stop at 600V, but there is more to this world than PVC. Of course could go with actively cooled cables, never have problems with that...😃 Or ceramic insulated cables fully rigid where the voltage is 4k, but then the battery itself has to be 4kV as well and at 3.7V/cell that is a tidy~ 1000 cells in series. Of course this generally means smaller cell size to achieve a parallel architecture and even the Old TESLA S had what? 7000 cells? This means only 7 in parallel which means worse cell leveling and shorter lifespan. 1 Quote Share this post Link to post Share on other sites
BradleyPNW + 282 ES June 17, 2020 28 minutes ago, Dan Clemmensen said: The SAE 1772 level 2 chargers in your earlier table are the ones you can put in almost any house in the US: they go up to 11.5 kW if you can provide a 60 A 240VAC circuit. Most of teh tens of thoudands of older charging stations in the US are also of this type. The enormous DC super chargers you mention in this post go from 150 kW on up, But this is usually between two charging stalls. This works out because one of the two cars is likely finishing up its charge (which requires the power to be reduced) while the other one is starting up its charge at full power. There is a third class of charger, at least in the Tesla universe. These are called "destination chargers" and are installed by businesses and usually reserved for their customers. These are DC chargers with power usually between 50 kW and 75 kW. Not too shabby if you are spending 2 hours shopping. With EVs, current driving habits matter and future driving habits more so. By the time EVs are a significant portion of the national vehicle fleet demanding (according to our current models of how people live and work) public charging stations we might not be going to shopping malls anymore. Or the grocery store. Or, if we do go to the grocery store it will only be long enough to pick up the groceries because we already did our shopping online. I suspect our charging demand will be satisfied at home because our driving habits will change. Corporations will drive most of the miles. Walmart and Costco fleets will charge "at home." Or battery swap, I don't know what business model will work for them. Corporate finance will take care of that. In 2035, I think we will be ok with lower power home charging because our lifeways will be different. Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 17, 2020 9 minutes ago, BradleyPNW said: With EVs, current driving habits matter and future driving habits more so. By the time EVs are a significant portion of the national vehicle fleet demanding (according to our current models of how people live and work) public charging stations we might not be going to shopping malls anymore. Or the grocery store. Or, if we do go to the grocery store it will only be long enough to pick up the groceries because we already did our shopping online. I suspect our charging demand will be satisfied at home because our driving habits will change. Corporations will drive most of the miles. Walmart and Costco fleets will charge "at home." Or battery swap, I don't know what business model will work for them. Corporate finance will take care of that. In 2035, I think we will be ok with lower power home charging because our lifeways will be different. Small local delivery trucks (mail, Amazon, UPS, some busses): EVs, charge "at home" but possibly with fairly powerful DC chargers. Heavy local vehicles (garbage, local supply, some busses): maybe H2 fuel cell, charge "at home". Long-haul trucks: eliminate. Use short-haul container-carrying trucks in conjunction with trains. Personal vehicles: charge at home. I have not charged anywhere but at home for more than 2 years. I use an ICE for long trips. The problem with "charge at home" is that not everyone has a parking spot where a charger can be be installed. This may be solvable by (say) 2030 by using autopilot to send your car to its central garage to sit overnight and charge, solving the problem of charging and also getting the cars off the streets. This does not eliminate the need for DC super chargers, which are needed for long trips, but it means that those super chargers provide a tiny percentage of the total charging. 1 Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 17, 2020 51 minutes ago, footeab@yahoo.com said: Nope: 600 Amps is just fine... of course no one will install it as the cables required to carry 600amps are 3cm in diameter before we add insulation which means actual diameter will be ~4cm or greater... This is not an exaggeration. Solid cables that size will require overhead crane to move them for granny/grandad and small women. The only way true fast charging happens is if much higher voltage becomes normal. Of course this means semi exotic insulation and rigid conductors as your plastics breakdown over 1000V. Yea yea, officially PVC etc stop at 600V, but there is more to this world than PVC. Of course could go with actively cooled cables, never have problems with that...😃 Or ceramic insulated cables fully rigid where the voltage is 4k, but then the battery itself has to be 4kV as well and at 3.7V/cell that is a tidy~ 1000 cells in series. Of course this generally means smaller cell size to achieve a parallel architecture and even the Old TESLA S had what? 7000 cells? This means only 7 in parallel which means worse cell leveling and shorter lifespan. The existing Tesla DC "supercharger" stations supply up to at least 150 kW at 480 VDC. That works out to 312.5 Amps, I think. Here is a picture of the cable (from https://commons.wikimedia.org/wiki/File:Tesla_Supercharger.jpg ): Quote Share this post Link to post Share on other sites
footeab@yahoo.com + 2,190 June 17, 2020 25 minutes ago, Dan Clemmensen said: The existing Tesla DC "supercharger" stations supply up to at least 150 kW at 480 VDC. That works out to 312.5 Amps, I think. Here is a picture of the cable (from https://commons.wikimedia.org/wiki/File:Tesla_Supercharger.jpg ): 🤔 Last I checked, they went with liquid cooling. The picture I deleted is of the old Low amperage charger. This is like comparing apples and oranges. You can dump hundreds of amps down a wire till it melts. No problems. You have temperature rating for the insulation is where the problem is. The fact I have to tell you this when you claim to be an electrical engineer, is rather poignant to your claim of being an engineer and an electrical one at that. Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 17, 2020 21 minutes ago, footeab@yahoo.com said: 🤔 Last I checked, they went with liquid cooling. The picture I deleted is of the old Low amperage charger. This is like comparing apples and oranges. You can dump hundreds of amps down a wire till it melts. No problems. You have temperature rating for the insulation is where the problem is. The fact I have to tell you this when you claim to be an electrical engineer, is rather poignant to your claim of being an engineer and an electrical one at that. At no point have I ever claimed to be an EE. In fact, I do not have an engineering degree, so I cannot be a "software engineer" in Canada. The US will let you call yourself an "engineer" based on your job function, but in Canada you must actually have an engineering degree. I am a retired computer systems architect. The picture, as I attributed it to Wikipedia, claimed to be a picture of a supercharger. If it is not, then we need to fix it at Wikipedia. Can you please provide a source? 1 Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 17, 2020 1 hour ago, footeab@yahoo.com said: 🤔 Last I checked, they went with liquid cooling. The picture I deleted is of the old Low amperage charger. This is like comparing apples and oranges. You can dump hundreds of amps down a wire till it melts. No problems. You have temperature rating for the insulation is where the problem is. The fact I have to tell you this when you claim to be an electrical engineer, is rather poignant to your claim of being an engineer and an electrical one at that. Further "research" (i.e., surfing the net) seems to show that the picture is indeed of the newer 150kW supercharger, and that the cable is indeed liquid cooled. The older supercharger stations maxed out at 105 kW, which at 480 VDC is 218.75 amps and (apparently) do not have liquid-cool cables. Quote Share this post Link to post Share on other sites
BradleyPNW + 282 ES June 17, 2020 2 hours ago, Dan Clemmensen said: Small local delivery trucks (mail, Amazon, UPS, some busses): EVs, charge "at home" but possibly with fairly powerful DC chargers. Heavy local vehicles (garbage, local supply, some busses): maybe H2 fuel cell, charge "at home". Long-haul trucks: eliminate. Use short-haul container-carrying trucks in conjunction with trains. Personal vehicles: charge at home. I have not charged anywhere but at home for more than 2 years. I use an ICE for long trips. The problem with "charge at home" is that not everyone has a parking spot where a charger can be be installed. This may be solvable by (say) 2030 by using autopilot to send your car to its central garage to sit overnight and charge, solving the problem of charging and also getting the cars off the streets. This does not eliminate the need for DC super chargers, which are needed for long trips, but it means that those super chargers provide a tiny percentage of the total charging. If I was Lord Emperor of a city I'd be tempted to provide free car 240V charging on the street. I don't know how to do it safely, but I'd like to see a cost benefit on free city-wide EV charging. Drop plugs from telephone poles. Quote Share this post Link to post Share on other sites
Enthalpic + 1,496 June 17, 2020 7 minutes ago, BradleyPNW said: If I was Lord Emperor of a city I'd be tempted to provide free car 240V charging on the street. I don't know how to do it safely, but I'd like to see a cost benefit on free city-wide EV charging. Drop plugs from telephone poles. Much of British Columbia has free charging places provided by BC hydro. The little highway rest stops have a washroom, trash can, free charging port, and even free wifi. 1 Quote Share this post Link to post Share on other sites
Bu22ard + 4 GC June 18, 2020 On 6/15/2020 at 10:32 PM, notsonice said: UK looks like the odd duck as in the US we 2 phase power to every house at a minimum (you could not run a dryer or electric stove on single phase) for the rest of Europe...... In northern and central Europe, residential electrical supply is commonly 400 V three-phase electric power, which gives 230 V between any single phase and neutral; house wiring may be a mix of three-phase and single-phase circuits, but three-phase residential use is rare in the UK. High-power appliances such as kitchen stoves, water heaters and maybe household power heavy tools like log splitters may be supplied from the 400 V three-phase power supply. To make us even more of an odd duck from 2025 all new properties will not be allowed to be fitted with a gas boiler. So for one thing gas is about 3p/KWh (granted at 85% efficiency) but elctricity is 16p/KWh. This means an average increase in energy costs of about £3500 per yer. It was trialed on a council estate in Scotland and drove residents from being comfortable to poverty. I don’t know what Kw a domestic electrical boiler would run at but it must be 5/6Kw? so add that to two charging cars and domestic appliances not only is my mind going to be blown but the main fuse too. im expecting to be able to fry eggs out on the tarmac outside my house. 1 Quote Share this post Link to post Share on other sites
Dan Clemmensen + 1,011 June 18, 2020 4 hours ago, Bu22ard said: To make us even more of an odd duck from 2025 all new properties will not be allowed to be fitted with a gas boiler. So for one thing gas is about 3p/KWh (granted at 85% efficiency) but elctricity is 16p/KWh. This means an average increase in energy costs of about £3500 per yer. It was trialed on a council estate in Scotland and drove residents from being comfortable to poverty. I don’t know what Kw a domestic electrical boiler would run at but it must be 5/6Kw? so add that to two charging cars and domestic appliances not only is my mind going to be blown but the main fuse too. im expecting to be able to fry eggs out on the tarmac outside my house. Yes, this is crazy, but I hope new properties will not use resistance electric heat. They will use heat pumps, and if the property is suitable for it they will use ground-source heat pumps. This gives you a lot more kWh thermal per kWh electric. An air-source heat pump will run at maybe 4 kW and a ground-source heat pump at maybe 2 kW for a typical house (varies hugely, just as with gas). Electric charging for 2 cars will be "smart" and not try to charge both at the same time, and can even co-operate with the heat pump to avoid excess instantaneous electrical demand. If your household has two drivers who each have long commutes, you will need to install a bigger electrical service entrance. In the US, the typical service entrance has grown over the years, and I suspect new-build UK homes will have hefty service entrances. Attempting to force a retrofit of existing homes is going to be a disaster. I just don't see it. As you say, the neighborhood distribution lines will need a complete rebuild. Crazy. My dream vision is using otherwise-curtailed wind and solar electricity to make CH4. This permits the older infrastructure to continue to operate, but with no fossil CH4, and this in turn allows for a long and non-crazy transition if warranted. Quote Share this post Link to post Share on other sites