5 ms·
Car charges overnight. Not wasting any more time on trips to the gas station. On longer trips, charge while eating.
by LarvaFX 6y ago
Car charges overnight. Not wasting any more time on trips to the gas station. On longer trips, charge while eating.
- layoutIfNeeded 6y agoMost people don’t live in houses with garages where they can charge their car.
- londons_explore 6y agoChargers will get cheap and public when electric cars become common. In the same way street lights are pretty much everywhere today. You could imagine a special type of paving stone that has a magsafe socket in, and you just pull a wire from your parked car to the kerb.
- lstodd 6y agoNo way. People can't get lousy fiber pulled to their houses and you're talking about multimegawatt electricity supply.
- londons_explore 6y agoI'm talking about slow chargers - the kind that are 60 amps or so AC. The kind that require no expensive electronics in the charger. The kind that'll take 12 hours for a full charge. Fast DC chargers will always cost more due to the need for expensive power electronics.
- lstodd 6y agoEven just +7 kVA per house means a complete rebuild of the grid. 1 MW would be enough for just ~150 chargers. And where would you get that megawatt at night? More base load, which means nuclear or fossil which means less niche for solar because no one would shut down such amount of base load generation each day. Besides 60 amps isn't exactly cheap in electronics. It might not require active cooling for the cable and the battery, that's true.
- Reason077 6y ago> "Even just +7 kVA per house means a complete rebuild of the grid." Only if every car in your neighbourhood is plugged in and pulling 7 kW at the same time. Smart charging solves this, by reducing charging during demand peaks (ie: 6pm when everyone is arriving home from work and plugging in at the same time), and increasing it later in the night when more capacity is available.
- lstodd 6y agoHowever you slice it, you have to deliver say 40KWh to that many cars overnight, or they fail to charge and thus are useless. So the grid has to handle that and even if you can get rid of extreme peaks with "smartness", you can't lower the cables and switches ratings much.
- Reason077 6y agoFirst of all, the average car does not need 40 kWh every day. The average driver in the USA drives 13,500 miles per year (far more than the average driver in the UK/Europe!) That's about 37 miles per day, so about 12.5 kWh per night on average at ~3 miles per kWh. And remember, those who are driving long distance are probably going to be using fast chargers on-route, so their domestic charging demand will be lower. Secondly, even if they did need 40 kWh every night, that only equates to 4 kW over a 10 hour charging cycle. Easily manageable by avoiding the typical late afternoon / early evening peaks. Most grids have a lot of spare capacity between, say, 9PM and 7AM.
- lstodd 6y agoYou fail to take into account inefficiencies in transmission and charging. That would multiply required input by a factor of two or three, depending where you measure it. So no. Switch most commute to electric - then at first grid goes down, then power plants struggle. "Most grids have a lot of spare capacity between, say, 9PM and 7AM" - that's not the grids we're talking about. HV circuits might not feel it, but something laid down for a suburb was scrupulously designed to carry only just enough, because it's basically burying refined metal, be it copper or aluminium. There is no spare even 4KW for every house and never has been because that would have cost more in about everything - meters, cables, multiple stages of step-down transformers, transmission lines, generation. Electicity is not free, never has been, and distibution costs are surprisingly a very important consideration.
- yholio 6y agoThe issue is not power electronics, but power supply. You might have a 60 Amps grid supply, or even a 100Amps split phase 120/240V as is typical for newer US homes, which allows drawing 24KW from the grid at full power. Your neighbor might have the same. But that doesn't mean everybody in your neighborhood can draw 24KW all night long. Those are maximal currents for intermittent loads like heaters, clothes driers etc. You might have a single 100KVA polemount transformer suppling a whole street and a single 15KV / 300Amp line servicing a whole neighborhood. When everybody attempts to draw even 5-10KW in the air-conditioning season, you get circuit breaks because the main feed is incapable of supplying sufficient power. The upgrading will be done but it will take a decade or more, especially considering the push from local municipalities towards buried power feeds which are very expensive.
- adrianN 6y agoElectric cars consume about 20kWh/100km. If your whole neighborhood needs to draw double digit kilowatts for 10h a night, you live in a neighborhood of long distance truck drivers.
- im3w1l 6y agoMaybe it doesn't happen every night, but only some nights. Say when everyone comes home from thanksgiving with empty batteries.
- adrianN 6y agoIf everyone wants to fill up their tank at once, the gas stations run out of gas. This doesn't happen with any regularity, which I take as an indicator that the scenario you're describing is very rare.
- im3w1l 6y agoThe gas system has buffering and slack at many levels. Cars store more mileage. Gas stations have a buffer. Gas stations can request more trucks come refill much easier than a grid can be upgraded. I don't think you proved anything.
- Reason077 6y agoUbitricity already have a pretty nice kerb-side charging solution, including sockets which integrate into existing street light poles: https://www.ubitricity.co.uk/ https://www.ubitricity.co.uk/ These are quite widely deployed in a few London boroughs.
- dfgdghdf 6y agoGreat, so we can turn London into a parking lot for electric cars. The solution for urban centres is to have fewer (but electric) cars.
- Reason077 6y agoNo, these aren't adding any additional parking spaces. Just allowing cars to be charged at existing ones. (I totally agree about fewer cars, but remaining ones must be electric. And electric cars need charging infrastructure.)
- trengorilla 6y agoYet.
- randunel 6y agoNot good enough for many of my friends, I'm afraid. It would definitely not be an option for me, I drive 1200km in roughly 12h - 14h each night, for 2w long tours: - Heviz to Saint Tropez 1200km - Empuriabrava to Malaga 1100km - Porto to Andorra 1100km - Krakow to Bucharest 1200km - other shorter trips (700km-800km) ----- - business trip Bucharest to Leipzig 1600km (I go much farther without passengers) - Leizig to London 1200km (slow ferry) - etc I drive a diesel and it's just excellent for my family's holidaying, we would be wasting considerable time charging, reducing the overall time to enjoy the tour's destinations.
- wastedhours 6y agoI mean, impressive mileage - but you must definitely be an outlier with those numbers in single trips I'd imagine. Also, if you're only do those kinds of numbers a few weeks a year, you could have an electric car for 50 weeks of the year and then hire a diesel one for the longer stints? That being said, it'll only be a couple more generations of tech before we're getting fast charge in the 15-20 minute ranges. By the time you've done a full-tank fill, used the toilets, picked up a few Rom bars in the shop and paid - you probably wont lose much time. (I'm still a car lover, but change is coming, and it'd be hard to argue with it in a few more years).
- bluGill 6y agoThe fixed costs of owning two cars means that it rarely works out. Rental cars can work, but again the math rarely works out because it is so expensive to rent a large car.
- jfk13 6y agoI also worry that in the hypothetical world where most people just own a small electric for local daily use, and rent a large diesel (or whatever) for the family holiday, demand for those larger, longer-range vehicles will be extremely seasonal. It may not be viable to maintain a large fleet of family-vacation-type vehicles just to satisfy the demand for summer holidays in August and ski trips in February.