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Comment: Re:Tesla enables Edison to win the endgame? (Score 1) 589

by AaronW (#49812483) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

Actually that's false. Most compressors are AC motors though some applications are moving towards DC. Brushless AC motors are fairly easy to make and don't require any electronics to control them, though high power ones will use a capacitor since 3-phase power is not generally available for residential use in the US. Most fans, blowers and compressors are AC motors. Some higher-end blowers use DC when full variable speed motors are needed.

Comment: Re:Tesla enables Edison to win the endgame? (Score 1) 589

by AaronW (#49812463) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

DC actually works quite well over long hauls. One nice thing about using HVDC instead of AC is that you can carry more current over the same wire since you no longer have to deal with the skin effect. It also makes it easier when it comes to synchronization. With HVDC they still have to periodically switch the direction of the DC current throught he lines.

Comment: Re:Please stop Elon. (Score 1) 233

by AaronW (#49777237) Attached to: Elon Musk Establishes a Grade School

I'd say Musk relies far less on tax dollars than Jobs did. Apple, despite all their billions, pays virtually no taxes. Tesla got a government loan and paid it off early with interest. There's a tax subsidy for buying an electric car, but it's no different if you buy a Leaf or a Model S. The carbon tax credits Tesla gets are not a major source of revenue and they don't come out of your taxes, but from companies that pollute.

Unlike Jobs, Elon is an engineer. He doesn't go around suing everyone over stupid patents either (he makes them available free of charge to everyone, using them for protection only).

Comment: Re:Non-answers (Score 1) 107

As it is, there have been more Volt fires than Tesla fires. In three separate tests the Volts tested by the NTSB caught fire. There was at least one Volt that have caught fire, one after it was rear-ended and the 12v battery caused it to burn up, completely burning up the interior of the car. None of the Tesla fires affected the passenger compartment.

Since Tesla's change there has not been a single new fire in the Tesla. Tesla is losing money, but they're doing what they need to do. All that money is being spent on growth which is required. They're making a 28% profit on every car sold and that money is being folded back into the company. The money is being spent on designing and tooling up the model X and model 3, which is exactly what they should be doing, as well as the gigafactory and building out their charging network, building service centers, etc. Given the demand for the model X (over 26,000 pre-orders) and their grid storage (sold out for the next year within a week), it looks like they're making the right choices.

The company is in a rapid growth phase. It would kill them to stop and try and be profitable now (which is what a short-sighted Wall Street CEO would do), since they need to look ahead to the future. Their future looks fairly bright given the high demand and customer satisfaction, especially given that they're doing virtually no advertising.

GM's Volt, while popular with Volt owners, has not been flying off the lots. It has been outsold by the Leaf, BMW i3 and Model S recently.

As for Ontario, I would not be surprised if they build out there in time. They're prioritizing their network based on need, building out the routes most owners need before building out less common routes. Their map of proposed chargers seems to be constantly changing, where I see superchargers popping up in places or along routes that were not previously shown. As far as cold climates, given it's one of the most popular cars in Norway my guess is that it does quite well in cold climates.

While the chemistry may be similar to laptop batteries, the batteries are NOT laptop batteries. There are many differences in order to increase the longevity and reliability and to reduce costs. Fires are a non-issue. There were a few and Tesla went back and addressed the problem and there have been none since. The risk of fire is much lower than for a gasoline powered car. The instances that caused the fires were rather extreme when you consider one of them was due to the car plowing through a concrete wall at 110MPH. Everyone walked away from that, I don't know that you could say the same thing if that happened with a Volt, if it could even reach 110MPH. The other was from running over a heavy duty trailer hitch which stuck up like a lance. Given where it hit, it would have seriously injured the driver of a Volt if it had happened since it would have gone right through the sheetmetal floor and into the driver's legs. In all cases, the fires did not affect the passenger compartment and they were rather slow burning. The one with the trailer hitch was made much worse by the fire department, who cut a hole in the top of the battery pack.

As for shaky companies, one of those companies recently declared bankruptcy and had a massive recall over a problem that was known for years that killed and injured a lot of people. When the model 3 comes out I don't think there will be much comparison between the Bolt and the model 3. Tesla will have a huge advantage over GM since their cost of batteries will be significantly lower and their batteries will be smaller and more energy dense. Tesla's electric motors are also less expensive since induction motors do not contain any rare-earth magnets. With the skateboard design Tesla uses the handling should also be better and it should have more space inside. It also wouldn't surprise me if Tesla offered all wheel drive for the M3 and incorporated other technologies from the Model S like self-driving support. Tesla also manufactures much more of their own stuff than GM. GM outsources a lot of stuff that Tesla does in-house, like the infotainment system (which runs on Linux and uses the Qt toolkit for the GUI), injection molding of plastic and more. It allows them to be much more nimble than a traditional car company and gives them tighter control on quality and to address problems more quickly.

It's also cheaper to drive a Tesla on a road trip than a Volt. The Superchargers are free for Tesla owners to use for the life of the car, though for the 60 and 70KWh battery it's a $2000 option to enable the support. It doesn't cost Tesla much in electricity to do a full charge, especially for those charging stations with Solar. Tesla is also using their batteries for grid storage to even out the load.

As for time added to a trip? I just drove from the Bay Area to Reno and back. I stopped to charge and eat dinner. My car was fully charged long before I was done with dinner. On the return trip I stopped at a fast food place to eat lunch. My car was charged before I finished my lunch. After visiting some friends along the way I stopped at another place for dinner, again, the car was fully charged long before I finished dinner. Hell, I had to make a pit stop in Truckee. I added another 40 miles of range during that, and I didn't need to charge my car. In the end, I spent zero time waiting for my car to charge. My car spent more time waiting for me. If I do need to wait, I don't have to wait at my car. My phone will alert me when I have enough charge to continue on.

Comment: Re:3.3kW is not right (Score 2) 107

3.3KW is a joke. On my model S, charging it to full at 10KW takes over 10 hours if it's empty. Most people don't drain their battery to zero and don't charge to 100% so it's fine for night time charging. I had no issues using at 5.7KW using my dryer outlet for most stuff, but 3.3 can be painful. Most public chargers I have used are 32A at either 208 or 240v, around 6.6KW. My father has a plug-in hybrid car with a 3.3KW charger and it's rather painful due to how slow it charges. At home I now use a 20KW charger which will fully charge the car in a bit over 5 hours. For my daily driving, around 40-50 miles, my car is fully recharged in about an hour at 20KW. That would change to 6 hours with a 3.3KW charger and if I drive 200 miles it would take almost 24 hours to recharge!

Granted, GM's cars have much smaller batteries, but any serious EV needs more than 3.3KW.

Comment: Re:The one question (Score 2) 107

It still has a lower coefficient of drag compared to a Prius or a Volt.

The Model S has a coefficient of drag of 0.24. The Prius is 0.26, the Volt is 0.28 and the Leaf is 0.32.


Even though the Tesla Model S is quite a bit bigger, it is the same as a Prius at 6.2 feet CdA.

Comment: Re:Translation (Score 2) 107

Sadly I agree with your comment. As a Tesla owner it's clear that GM and the others just don't get it. There's a reason that the Cadillac ELR failed miserably and that Tesla is eating everyone else's lunch when it comes to EVs. When gas got cheap, sales of the other EVs fell significantly. Tesla still can't keep up with demand yet they do basically zero advertising. They've worked hard to address all of the issues people have with EVs, including range, charging and performance. The people who complain about how long it takes to charge a Tesla don't have any experience with it.

The only reason that the J1772 standard can handle 20KW is because Tesla fought tooth and nail for it. GM and the others would have been happy with a 3.3KW limit. They also should have adopted something like Tesla's standard for fast DC charging rather than the Frankenstein SAE combo plug or ChaDeMo.

When it comes to battery technology, Tesla is years ahead. Their batteries are much higher capacity and much cheaper than what GM is using.. Despite being manufactured by Panasonic, Tesla owns much of the IP in their batteries and has numerous patents on them. Once their gigafactory comes online, Tesla's cost for batteries will drop by at least 30%. Their cost are already the lowest in the industry in terms of $$$/KWh with the highest energy density for automotive grade batteries.

They've addressed the whole chicken vs egg problem with respect to rapid charging. Instead of waiting for people to build level 3 chargers, they are building their own network and locating them based on need, not just at dealerships (i.e. Nissan). Their chargers are also capable of much higher output than most of the other chargers (120-135KW vs 62.5KW (ChaDeMo) or 90KW (SAE combo)). Tesla has already had several years of experience with their superchargers and already has a large network of them along popular routes. By the time the low cost model 3 comes out they will be just about everywhere, even for out of the way places. Right now there are very few SAE combo chargers and they're primarily located in cities and almost none of them are located along major routes, making it impossible to do road trips without long charge times (especially with only 3.3KW charging!). There are some SAE combo chargers in the Bay Area and Los Angeles, but virtually none in between. Meanwhile I have my choice of routes with Tesla's supercharger network where I can drive from San Diego all the way to Edmonton Canada or to the East Coast. ChaDeMo chargers are also usually located in cities and not between them. They also tend to max out between 40 and 62.5KW. Tesla owners with the ChaDeMo adapter are reporting that many of these ChaDeMo chargers overheat and even start smoking, even when it's 0F outside because they can't handle the load, which is quite a bit less than what the Tesla chargers put out. Thankfully it looks like ChaDeMo is dying out.

Their skateboard design also helps maximize interior and cargo space compared to big humps under the seats and down the center of the car. They redesigned the car from the ground up for their Model S rather than taking an existing gasoline design and converting it to electric. I've taken my Model S places that would be impossible for just about any other EV except maybe the Roadster, and the ease of road trips with it becomes easier all the time.

  They also showed that it's possible to design an EV with a low coefficient of drag that isn't butt ugly or looks weird.

The problem with GM is their marketing is so conservative that they compromise everything all to hell which is why GM's cars are ugly, have limited charging and limited range. I have little doubt that there won't be much comparison between the Tesla Model 3 and the GM Bolt. I think Bolt is what the customers will do when they compare the two.

Comment: Re:Its not just a range anxiety issue (Score 2) 107

My experience driving my Tesla for two years is that the whole range anxiety thing is disappearing very quickly. I just got back from a trip from the Bay Area to Reno and back. In every case where I stopped to grab lunch or dinner my car was fully charged before I finished my meal. In one case I stopped just to make a quick pit stop and pick up a 6-pack of cider and by the time I returned to my car I had added another 40 miles of range, and the only reason I stopped was I had to stop, not my car. I had my choice of places where I could stop too as well as a choice in routes I could take. The car also tells me how much range I will have once I reach the destination and will route me to superchargers along the way if needed. This is a vast improvement over a year ago when I made the same trip. A year ago there was one supercharger that was somewhat off the route. I had to go to Folsom to charge then switch over to highway 80. I arrived in Reno with around 20 miles of range left. This time the software was updated to automatically take the superchargers into account. By the end of this year it looks like 5, 101 and 395 will be well covered for north/south and by next year 99 will also be covered. I can also charge at just about any RV park that has power hookups and Tesla has been seeding 20KW chargers at many hotels in vacation areas like Carmel and Monterey. By the time their low cost car will be available you should be able to drive just about anywhere.

The time for charging is not the big deal people make it out to be. In most cases there are places to eat or shop close by.

On the return trip I stopped in Truckee to grab a quick bite at a Panda Express. Before I finished my car was fully charged. I could have driven a lot further but I was hungry. Later I stopped in Manteca to charge and eat and again, my car was fully charged well before I finished eating. Charging is not like filling up with gas. When filling up my gas car I need to get out of the car and stand there filling it up. There is no reason to stay at the car while it is charging although you could. It's also a chance to stretch your legs and use the money you would normally spend on gas on food or other things.

Comment: Re:Non-answers (Score 4, Informative) 107

I agree. It also just goes to show how far behind GM is compared to Tesla. I've had my Tesla Model S for over two years and I have to say that GM's response has been pathetic at best. Their Cadillac ELR was supposed to be the Tesla killer, it failed miserably. Tesla is years ahead when it comes to battery technology, having much higher energy density at much lower cost. Tesla's skateboard design is also much better when it comes to interior room and storage space.

Saying a 3.3KW charger is adequate is a joke. The only reason that it's even possible to go up to 20KW with the SAE J1772 connector is because Tesla fought hard for it. I have a 20KW charger at home and it comes in handy. Sadly few public charging stations come anywhere near that, though most I've used will handle at least 6KW (30-32A, 208/240V) and the RV hookups are often 10KW (40A, 240V). Usually I rarely bother to use the public charging units unless they're free since it's cheaper to just charge at home where I can charge at 80A, 240V which adds around 55 miles of range per hour. The one time I had to use a public charging station to reach my destination it was painful since it only added 18 miles of range per hour so I was stuck an hour waiting until I had enough range to reach the Gilroy supercharger. Fortunately it looks like by the end of the year they'll have a spot around Monterey.

GM also has no real answer to Tesla's supercharger network which is years ahead of anyone else. I just used it a few days ago to travel from the Bay Area to Reno. In every case, it took longer for me to eat lunch or dinner than it took for my car to charge. Hell, I added 40 miles of range (which I didn't even need) when I stopped in Truckee just to use the restroom and pick up a 6-pack of hard cider at Safeway. Tesla's network is building out very quickly (go to their supercharger site to see). I made the same trip to Reno last year but this year there were 4 more superchargers along the route. Last year I had to make a short jog over to Folsom to charge, this year I had my choice of places along the route. Right now there are multiple routes across the country. I can drive all the way from San Diego to Edmonton, Canada or anywhere along the East Coast. By the end of this year it looks like most of the major north/south routes in California will be covered, 5, 101 and 395 and by the end of next year 99 will also be covered. They have also been helping seed a lot of hotels around the country with 20KW chargers in a lot of the vacation spots.

As far as batteries go, Panasonic may be manufacturing Tesla's batteries, but Tesla owns much of the intellectual property of their batteries and holds numerous patents on them. The Tesla batteries are quite a bit cheaper with a higher energy density and they seem to be fairly reliable as well.

Tesla has also shown that it's possible to create a car with a very low coefficient of drag that isn't butt ugly. I say this as a former Prius owner.

Comment: Re:AI is not predictable to humans (Score 1) 408

That reminds me of the first accident I was in. I was 16 and had only been driving for around a year (6 months with a license) when while driving home from school the car in front of me suddenly changed lanes without warning. In front of me was a car stopped to make a left turn over a pair of double yellow lines (clearly illegal). The car I drove (one of my parent's cars, a 1970 Toyota Corona) had really crappy brakes, they were supposed to be power brakes, but I think Toyota forgot the power part. With every ounce of strength I managed to stop in time (it was impossible to make the wheels lock up, the brakes were that crappy!) but the car behind me wasn't so lucky. He hit me, forcing me into the car in front (who should never have stopped there to begin with). When the cop arrived the first thing he said was I was at fault, likely because I was 16, until it was shown that the only reason my car got sandwiched was due to the driver behind me and the stupid woman who stopped to make a left turn there. So even though I rear-ended the car in front of me, I wasn't at fault. I hated that car but the damned engine wouldn't die on it.

Comment: Re:Editorializing... (Score 1) 408

This reminds me of my grandmother who drove with a suspended license and Alzheimers. She'd get lost driving around the block and my grandfather wasn't much better. Hell, she even got a new car when the dealership convinced her to trade in her old car because the check engine light came on for only a few hundred dollars, even though she didn't have a valid drivers license and obviously wasn't all there. Thankfully the police were finally able to put a stop to her driving and we were able to commit her to a place where she could get the proper care. We didn't know (but suspected) that she was driving and the way the laws are it can be difficult to stop. When she showed up at the retirement home where my grandfather was staying they called the police because they knew she shouldn't be driving and she got belligerent, suddenly making it a lot easier to get her committed and take away her keys for good.

Comment: Re:Not convinced (Score 1) 408

4 out of 48 is useless. You need to look at the number of miles driven. I suspect that these cars drive a lot of miles. A more meaningful metric is how many accidents per 100K miles driven. Also one needs to look at who was at fault for the accident and if it was avoidable. In two of the four cases, the cars were not under autonomous control at the time. I suspect that when all of the data is taken into account that the cars are safer than average.

Comment: Re:Fault may not be the right measure. (Score 1) 408

I saw a pedestrian get hit because of this. The pedestrian waited until the sign said "don't walk" and the light for cross traffic turned green before she proceeded to walk across the street. One lane had a line of cars, the other lane was free and the light was green for some time while we waited. The pedestrian stepped right in front of a truck who had the right of way. Fortunately two of the people in the car I was in were EMTs. It was a clear case of the pedestrian being at fault. A few weeks later the exact same thing almost happened but at the last second the pedestrian realized his mistake and ran and missed getting hit by only a few inches.

Comment: Re:Fault may not be the right measure. (Score 1) 408

Even with defensive driving some accidents are unavoidable. I've been in several where I was stopped with nowhere to go. Once I was waiting in traffic at an off-ramp and got side-swiped because the other inexperienced driver panicked when changing lanes. I've been backed into while stopped in a parking lot (despite laying on the horn). I've been rear-ended after being forced to panic stop by an idiot driver who stopped to make a left turn over a double yellow line. The car in front of me suddenly changed lanes, I stopped (barely, I was 16 and my parent's clunker had wish brakes, you wish they'd work), the car behind me didn't. My favorite was when I was driving highway 17 in the Santa Cruz mountains during a heavy rainstorm. A car two cars ahead of me hit the brakes on a curve, lost control and did a 360 spinout, hitting the car in front of me. I avoided him, or so I thought, until his car rear-ended me. That took talent! Fortunately no damage to my clunker.

Things are not as simple as they seems at first. - Edward Thorp