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Electric buses at waterloo
On Mon, 16 Jul 2018 12:29:16 +0100, Roland Perry wrote:
In message , at 12:08:38 on Mon, 16 Jul 2018, David Cantrell remarked: What's important for the EV-charging scenario is that is if several dozen houses are supplied by an 200A street main at 230v from the local substation, how can more than a handful charge an EV overnight at 50 amps? They won't all need to fully recharge a car every night. Of the many cars parked on a street, plenty of them just aren't used most days. And of those that are used on any given day, plenty aren't used much - just a trip to the shops, or the school run, or to a nearby employer. This depends a lot on the local demographic. There are plenty of estates where at least one breadwinner per household is likely to drive to work (and the national average commute is 67% by car, 30mins). Where I live that's dominated by the 35 mile round trip to Cambridge, unless they take the fastest route which is 50 miles round trip. So with a 35 mile round trip, maybe averaging 35mph, that's one hour per day, or five hours usage a week, add on another hours usage for bit for shopping etc and a day off on sunday and that leaves some 162 hours a week for a charge to take place. 210 miles in a week is just under 11000 miles a year which is high by average private motorist standards (see below) At 18kWh/100 miles for a Nissan Leaf (BMW i3 is similar as is the claimed performance for the Tesla Model 3) then it needs some 1980kWh per annum of charge. If 100% of that charge takes place at home then it can take place spread across 100 hours a week (12 hours a day weekdays + 24 hours sunday + 16 hours on a saturday) It needs 38 kWh per week to do those 210 miles Ignoring charging losses that equates to an average mains supply load when on charge of around 380W, or 1.6A at 240v As it is the average UK private mileage is (was) 7900 miles in 2013, down from 9200 miles in 2002 https://www.bbc.co.uk/news/uk-england-28546589 So for the 'average private motorist' the average mains supply load when on charge, for charging purely at home, drops to around 270W or 1.125A at 240v -- |
Electric buses at waterloo
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Electric buses at waterloo
On 17/07/2018 11:50, The Other Mike wrote:
On Mon, 16 Jul 2018 08:59:01 +0000 (UTC), wrote: It seems to me the whole charging problem of mass ownership of electric cars has been kicked into the long grass. As usual politicians will only react when they have to when the load on the grid either local or national becomes critical whereupon headless chicken mode will be engaged. Maybe you'll throw in the argument about cables draped across pavements but a couple of hours of work on the legislation would see that dangerous and unsociable practive outlawed overnight. So outlawing electric cars for something approaching 50% of the population who can only afford a flat or terraced house. The 'poor' without places to park offroad will have to do without personal transport charged at home somewhere around 2050-2060 They better get planning now because there are only 22 years to change habits if they are to buy a new hydrocarbon fuelled car. Maybe they could start saving now to buy a bigger property or in the intervening period public transport could fill the gap and get the vast majority of cars off the road regardless of their fuelling. Oh, boy. "Start saving now to buy a bigger property". I'd love to, would you like to persuade my boss to double my wages in real terms? As for public transport picking up the load, I live in the best place I can afford, and while until the firm moved recently it took ten minutes to drive to work, doing the same trip by public transport took at least 40 minutes with two longish walks and an average ten minute waitfor a bus halfway, or a short walk, and a direct bus that takes 58 minutes. Now they've moved, it still takes ten minutes to drive, but well over an hour to get there by public transport. Now consider, I often work a 14 hour day, and consider I need at least 8 hours at home every night for sleep and personal hygiene... See this for a worked example on electricity usage for the 'average UK motorist' Link? All I see is a message ID. -- Tciao for Now! John. |
Electric buses at waterloo
On Tue, 17 Jul 2018 11:50:18 +0100
The Other Mike wrote: On Mon, 16 Jul 2018 08:59:01 +0000 (UTC), wrote: It seems to me the whole charging problem of mass ownership of electric cars has been kicked into the long grass. As usual politicians will only react when they have to when the load on the grid either local or national becomes critical whereupon headless chicken mode will be engaged. We've already been here before and there is NO problem. The additonal supply requirements are negligible if you take your head out of the sand, forget this idea of a two minute charge because thats how long it takes for your hydrocarbon car to refuel to do 600 miles to the back end of nowhere without stopping for urinating or whatever and realise the average car is, with absolute certainty, sat doing absolutely nothing but depreciating for many thousands of hours a year. Around half of that almost certainly at home. So what? Its the energy that it uses when it is moving thats the issue. When I last commuted to work by car it was a round trip of about 40 miles, say 2 gallons of diesel which is approx 300 million joules of energy. Assuming for ease of calculation my car is around 33% efficient that'll be 100M joules used for moving. Electric cars are (according to google) around 50-60% efficient from grid to wheel so say an electric car needed 200M to do the same job. With a 30 amp supply that'll take 200,000,000 / (240 * 30) = 27777 seconds = 7.7 hours to charge. Now I don't know about you, but I suspect an extra 240 * 30 = 7.2KW load multiplied by however many houses have electric cars multiplied by 7 hours will be quite a bit extra for the local substation to cope with. |
Electric buses at waterloo
On Tue, 17 Jul 2018 12:25:25 +0100, John Williamson
wrote: On 17/07/2018 11:50, The Other Mike wrote: On Mon, 16 Jul 2018 08:59:01 +0000 (UTC), wrote: It seems to me the whole charging problem of mass ownership of electric cars has been kicked into the long grass. As usual politicians will only react when they have to when the load on the grid either local or national becomes critical whereupon headless chicken mode will be engaged. Maybe you'll throw in the argument about cables draped across pavements but a couple of hours of work on the legislation would see that dangerous and unsociable practive outlawed overnight. So outlawing electric cars for something approaching 50% of the population who can only afford a flat or terraced house. The 'poor' without places to park offroad will have to do without personal transport charged at home somewhere around 2050-2060 They better get planning now because there are only 22 years to change habits if they are to buy a new hydrocarbon fuelled car. Maybe they could start saving now to buy a bigger property or in the intervening period public transport could fill the gap and get the vast majority of cars off the road regardless of their fuelling. Oh, boy. "Start saving now to buy a bigger property". I'd love to, would you like to persuade my boss to double my wages in real terms? As for public transport picking up the load, I live in the best place I can afford, and while until the firm moved recently it took ten minutes to drive to work, doing the same trip by public transport took at least 40 minutes with two longish walks and an average ten minute waitfor a bus halfway, or a short walk, and a direct bus that takes 58 minutes. Now they've moved, it still takes ten minutes to drive, but well over an hour to get there by public transport. Now consider, I often work a 14 hour day, and consider I need at least 8 hours at home every night for sleep and personal hygiene... See this for a worked example on electricity usage for the 'average UK motorist' Link? All I see is a message ID. Yes it's message id, to another posting here It's usable by most newsreader for decades, failing that == So with a 35 mile round trip, maybe averaging 35mph, that's one hour per day, or five hours usage a week, add on another hours usage for bit for shopping etc and a day off on sunday and that leaves some 162 hours a week for a charge to take place. 210 miles in a week is just under 11000 miles a year which is high by average private motorist standards (see below) At 18kWh/100 miles for a Nissan Leaf (BMW i3 is similar as is the claimed performance for the Tesla Model 3) then it needs some 1980kWh per annum of charge. If 100% of that charge takes place at home then it can take place spread across 100 hours a week (12 hours a day weekdays + 24 hours sunday + 16 hours on a saturday) It needs 38 kWh per week to do those 210 miles Ignoring charging losses that equates to an average mains supply load when on charge of around 380W, or 1.6A at 240v As it is the average UK private mileage is (was) 7900 miles in 2013, down from 9200 miles in 2002 https://www.bbc.co.uk/news/uk-england-28546589 So for the 'average private motorist' the average mains supply load when on charge, for charging purely at home, drops to around 270W or 1.125A at 240v == -- |
Electric buses at waterloo
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Electric buses at waterloo
On Tue, 17 Jul 2018 12:25:25 +0100, John Williamson
wrote: On 17/07/2018 11:50, The Other Mike wrote: On Mon, 16 Jul 2018 08:59:01 +0000 (UTC), wrote: It seems to me the whole charging problem of mass ownership of electric cars has been kicked into the long grass. As usual politicians will only react when they have to when the load on the grid either local or national becomes critical whereupon headless chicken mode will be engaged. Maybe you'll throw in the argument about cables draped across pavements but a couple of hours of work on the legislation would see that dangerous and unsociable practive outlawed overnight. So outlawing electric cars for something approaching 50% of the population who can only afford a flat or terraced house. No, of course not. There will be plenty of other places to recharge, whether in car parks, roadside chargers, motorway services, fast charger stations, etc. As the number of EVs increases, there will be a growing network of chargers. Even the major oil companies see it as an attractive market: https://www.theguardian.com/business/2018/jun/28/bp-buys-uks-biggest-electric-car-charger-network-for-130m https://uk.reuters.com/article/uk-newmotion-m-a-shell/shell-buys-newmotion-charging-network-in-first-electric-vehicle-deal-idUKKBN1CH1R5 Consortia of car companies are doing the same: https://electrek.co/2017/11/03/ultra-fast-electric-car-charging-network-unveiled-by-bmw-mercedes-ford-volkswagen/ |
Electric buses at waterloo
In message , at 11:41:13 on
Tue, 17 Jul 2018, The Other Mike remarked: What's important for the EV-charging scenario is that is if several dozen houses are supplied by an 200A street main at 230v from the local substation, how can more than a handful charge an EV overnight at 50 amps? They won't all need to fully recharge a car every night. Of the many cars parked on a street, plenty of them just aren't used most days. And of those that are used on any given day, plenty aren't used much - just a trip to the shops, or the school run, or to a nearby employer. This depends a lot on the local demographic. There are plenty of estates where at least one breadwinner per household is likely to drive to work (and the national average commute is 67% by car, 30mins). Where I live that's dominated by the 35 mile round trip to Cambridge, unless they take the fastest route which is 50 miles round trip. So with a 35 mile round trip, maybe averaging 35mph, that's one hour per day, or five hours usage a week, add on another hours usage for bit for shopping etc and a day off on sunday and that leaves some 162 hours a week for a charge to take place. The commuter will typically be at home for 14hrs a working day, that's 98hrs. What they do at weekends is very much a lifestyle issue, but they could never clock up another 64hrs indoors. 210 miles in a week is just under 11000 miles a year which is high by average private motorist standards (see below) Average motorists include those who aren't commuters. At 18kWh/100 miles for a Nissan Leaf (BMW i3 is similar as is the claimed performance for the Tesla Model 3) then it needs some 1980kWh per annum of charge. If 100% of that charge takes place at home then it can take place spread across 100 hours a week (12 hours a day weekdays + 24 hours sunday + 16 hours on a saturday) It needs 38 kWh per week to do those 210 miles Ignoring charging losses that equates to an average mains supply load when on charge of around 380W, or 1.6A at 240v As it is the average UK private mileage is (was) 7900 miles in 2013, down from 9200 miles in 2002 https://www.bbc.co.uk/news/uk-england-28546589 So for the 'average private motorist' the average mains supply load when on charge, for charging purely at home, drops to around 270W or 1.125A at 240v You need to read the National Grid papers on the subject, which suggest that even with reasonable remediation measures the whole thing falls over at about 20% EV penetration by 2030. -- Roland Perry |
Electric buses at waterloo
On Tue, 17 Jul 2018 13:33:55 +0100
Recliner wrote: On Tue, 17 Jul 2018 12:25:25 +0100, John Williamson wrote: On 17/07/2018 11:50, The Other Mike wrote: On Mon, 16 Jul 2018 08:59:01 +0000 (UTC), wrote: It seems to me the whole charging problem of mass ownership of electric cars has been kicked into the long grass. As usual politicians will only react when they have to when the load on the grid either local or national becomes critical whereupon headless chicken mode will be engaged. Maybe you'll throw in the argument about cables draped across pavements but a couple of hours of work on the legislation would see that dangerous and unsociable practive outlawed overnight. So outlawing electric cars for something approaching 50% of the population who can only afford a flat or terraced house. No, of course not. There will be plenty of other places to recharge, whether in car parks, roadside chargers, motorway services, fast charger stations, etc. As the number of EVs increases, there will be a growing network of chargers. Even the major oil companies see it as an attractive market: They'll still take far longer to recharge than an ICE vehicle. Therein lies the problem. |
Electric buses at waterloo
On Tue, 17 Jul 2018 13:33:58 +0100
The Other Mike wrote: On Tue, 17 Jul 2018 11:46:47 +0000 (UTC), wrote: the sand, forget this idea of a two minute charge because thats how long it takes for your hydrocarbon car to refuel to do 600 miles to the back end of nowhere without stopping for urinating or whatever and realise the average car is, with absolute certainty, sat doing absolutely nothing but depreciating for many thousands of hours a year. Around half of that almost certainly at home. So what? Its the energy that it uses when it is moving thats the issue. Really? No wait, what am I thinking - its the energy they use when they're switched off and not moving that really matters! When I last commuted to work by car it was a round trip of about 40 miles, say 2 gallons of diesel which is approx 300 million joules of energy. 20mpg from a diesel 'car'? I could nearly get that from a UNIMOG This involved heavy traffic and is a real world mpg, not what you might have been suckered into believing in the EU test figures. Now I don't know about you, but I suspect an extra 240 * 30 = 7.2KW load multiplied by however many houses have electric cars multiplied by 7 hours will be quite a bit extra for the local substation to cope with. How about using real world kWh/distance travelled published for all commercially available electric cars rather than 'guessing'? Guessing? Sorry, was that pre-school maths too complex for you? Plus get this idea out of your head that everyone today drives around with a near full tank of hydrocarbon fuel and/or they all need to do x hundred miles a day and they need to emulate anything even remotely resembling your declared 'charging' regime There are enough people who do high mileages for whom an electric car currently is not viable. Sure, for the old lady who only goes to the supermarket once a week or the guy who drives 2 miles to work and back - win. 27kWh spread across 100 hours per week 'at home', or just 270W when on charge Recharge with 270W? LOL , yeah ok, if you hardly went anywhere you could trickle charge on that :) Here's some facts for you - a nissan leaf has a 40kwh battery. So to do a full recharge with 270W assuming no losses would take: 40,000 / 270 / 24 = 6 *DAYS* Feel free to point out where I've made an error in that. Or do you think a 6 day recharge time is reasonable? |
Electric buses at waterloo
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Electric buses at waterloo
On Tue, 17 Jul 2018 16:39:53 +0100
John Williamson wrote: On 17/07/2018 14:01, wrote: There are enough people who do high mileages for whom an electric car currently is not viable. Sure, for the old lady who only goes to the supermarket once a week or the guy who drives 2 miles to work and back - win. If I were only using it to commute, a G-Wiz would have enough range for almost a week, but if I want to go any distance at all, I need a proper ICE car. My brother owns an electric car. When it was new, it did about 100 miles per charge, so it was useful for trips to his kids' sports fixtures in the same county as well as going shopping in the nearest town a few miles away. After less than 5 years, he has to get his Ford Focus out if it's more than a 60 mile round trip. Also, when his electric car was new, he could just plug in to one of the (then rare) charging points and top it up for free while he was shopping. Now, he is not guaranteed a charge when he's away from home as the points are all being hogged by plug in hybrids, and he has to pay to top up due to changes in the systems. Progress... I'm guessing battery life is going to be a serious issue with electric cars unless a viable alternative to lithium ion is found. The amount of waste generated, or altenatively the amount of energy required to recycle them is going to be horrendous. work. The Ford, on the other hand still does the same distance on a tank of fuel that it did when it was new ten years ago, and the same applies to his 45 year old MGB. But I presume the mgb has probably has had some major servicing and repairs done on the engine. Those 60s and 70s engines really didn't last very long without it. |
Electric buses at waterloo
John Williamson wrote:
My brother owns an electric car. When it was new, it did about 100 miles per charge, so it was useful for trips to his kids' sports fixtures in the same county as well as going shopping in the nearest town a few miles away. After less than 5 years, he has to get his Ford Focus out if it's more than a 60 mile round trip. Also, when his electric car was new, he could just plug in to one of the (then rare) charging points and top it up for free while he was shopping. Now, he is not guaranteed a charge when he's away from home as the points are all being hogged by plug in hybrids, and he has to pay to top up due to changes in the systems. Progress... What model of car is it? All are not created equal. The battery lifetimes seem much worse on those without a battery temperature management system (eg Nissan Leaf), against those with liquid cooling. Theo |
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