Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?

Comment: I just wish I could see the stars! (Score 3, Informative) 83

The light pollution where I live is so bad that only a few stars are visible on a clear night. I frequently wish all the street lights could be turned off for a change. I doubt that the switch to LED street lights will improve things. In fact, I imagine it will make things worse for the local observatory (Lick) since it is relatively easy to filter out sodium.

Comment: Re:Newest battery technology? (Score 1) 125

by AaronW (#48682331) Attached to: Tesla Roadster Update Extends Range

I can't compare to other performance cars since this is the first one I've owned. It does great on the highway and passing though I imagine some of the other performance cars do better. There is no lag which is nice so it is extremely responsive. Handling is quite good, not as good as the P85+ but it does quite well, especially given its weight. It's certainly fun to drive on those windy mountain roads, and the high torque does quite well on steep grades. It's also quite forgiving considering how much torque it has and the traction control works extremely well at holding the tires at the edge with just a little slip unlike other cars I have driven. I haven't driven the P85D yet and they stopped making the P85 (which is what I have).

Comment: Re:Call me when.. (Score 5, Insightful) 125

by AaronW (#48677807) Attached to: Tesla Roadster Update Extends Range

The difference is that I can charge at home overnight to a full battery in my garage and I spend 5 seconds plugging in at night and 5 seconds unplugging in the morning. The beauty of it is that I don't need to go to a filling station except on long trips.

As more and more charging stations go in, most charging will happen at home and/or work where charging time doesn't matter.

Comment: Re:Newest battery technology? (Score 2) 125

by AaronW (#48677801) Attached to: Tesla Roadster Update Extends Range

Currently Tesla charges at over 250 amps with their superchargers and I charge mine at home at 80 amps. As you say, though, the biggest limitations will be cooling and just getting that much current into the car. I think it's amazing that Tesla is able to handle 120KW through their current connector (and I hear they're experimenting with 150KW). None of the other charging connectors come close to this. They might also need to increase their active cooling of the batteries.

Right now my P85 will draw upwards of 310KW from the battery pack, but only for short bursts when accelerating hard.

Charging this fast might require something similar to their battery swapping, with a large connector built directly in to the battery along with support for the coolant loop where something comes up under the car to charge and actively cool the battery when handling so much current.

Comment: Re:That's quite a charge... (Score 1) 133

by AaronW (#48639117) Attached to: Tesla About To Start Battery-Swap Pilot Program

That's the idea. Basically the idea is that you do most charging at home. When I'm planning to go on a long trip I'll set up my Tesla to charge to 100% before I leave home so I spend less time at the supercharger on the way to my destination. Battery swapping doesn't make a lot of sense except for long trips, for example between SF and LA.

Comment: Re:Begun ... (Score 4, Informative) 330

by AaronW (#48614055) Attached to: 11 Trillion Gallons of Water Needed To End California Drought

They've been doing that for years in my city to brackish water to supplement the water supply. The problem is that these last few years have been exceptionally dry. You can't just build desalination plants overnight, especially for the amount of water we're talking about, plus it needs to be transported quite a distance and is very expensive. Most of the water is used for agriculture. California produces around 1/3 of all of the food in the country.

Comment: Re:LA public transportation sucks (Score 2) 605

by AaronW (#48606375) Attached to: Waze Causing Anger Among LA Residents

Originally it was built with street cars until those were ripped out to be replaced by buses, funded by the likes of Firestone, General Motors, Standard Oil (Chevron), Phillips Petrolium (Conoco Phillips), Mack Truck and others.


San Francisco is one of the few cities that retained its street cars and is much better because of it.

Comment: Re:Move to a gated community (Score 1) 605

by AaronW (#48606327) Attached to: Waze Causing Anger Among LA Residents

In Los Angeles, given the limited available land area and high prices and how painful it is to shut down lanes, freeways can be far more expensive to build, probably more like 150-00M/mile. And don't get started on rail. I think extending BART is costing upwards of $1B/mile in places. LA freeways also need to be built to withstand major earthquakes which also increases the cost, especially for bridges. With earthquakes, two tiered freeways are a lot more expensive or you end up with problems like this.

With all of the land being so densely populated, putting through a new freeway becomes extremely costly, especially since nobody wants their neighborhood to be split by a major freeway.

Comment: Re:Move to a gated community (Score 1) 605

by AaronW (#48606239) Attached to: Waze Causing Anger Among LA Residents

One of the freeways I take to work had a choke point where it went from 4 to 3 lanes. Once they expanded it 4 lanes the entire way traffic didn't move just 25% faster. It was more like 200% faster during rush hour. I'll never understand why people always wait for the very last instant to merge, slowing everyone down.

Comment: Re:Move to a gated community (Score 1) 605

by AaronW (#48606199) Attached to: Waze Causing Anger Among LA Residents

Wrong. The fact that they are public residential roads does not mean that they're designed for the kind of traffic that's flowing over them. They were designed to service the residents who live there. It becomes a public safety issue when emergency vehicles cannot get where they need to go over city streets due to the streets being clogged with traffic they were never designed to handle. Also, the gasoline taxes do not cover the cost of the roads, especially at the federal level where the federal program is getting close to being insolvent.

My neighborhood was getting filled up by people parking for the nearby BART station when BART started charging fees for parking. They made it impossible for locals to park and were dumping trash all over the place and causing a lot of other problems. It made it impossible for construction vehicles to park or for people to visit. They went so far as to start cutting the local trees and bushes when they got in their way. The City said if 90% of the homeowners could agree for a no parking during a two hour window they'd implement it. They had no problem getting over 90% of the homeowners to agree to this. Other cities solve this using parking permits.

Comment: Re: Only 118,746 ... (Score 1) 87

by AaronW (#48605255) Attached to: California's Hydrogen Highway Adds Another Station

It's not just Tesla with their gen 3. Nissan and Audi are also planning 200+ mile EVs and Nissan is looking at keeping the costs down as well. GM, Ford and BMW aren't sitting still either. It's just a matter of the battery prices to continue their downward trend in cost and upward trends in capacity and performance. The writing is on the wall for fuel cell vehicles and has been for a while. Tesla's gigafactory alone should drop their battery prices by at least 30%.

Comment: Re:I suppose this is a good thing... (Score 1) 87

by AaronW (#48605207) Attached to: California's Hydrogen Highway Adds Another Station

Show me a worthwhile fuel cell car?

Try driving any of those cars outside of the few hydrogen filling stations. Oh wait, you can't. By the end of next year only a few cities will be linked up by hydrogen filling stations. I can drive my Tesla from San Diego to Vancouver today, or across the country. By the end of next year most of the nation will be covered by rapid chargers where only a few major cities will be covered by hydrogen. I can also charge any place there's an outlet or at most RV parks if need be. Most of my charging happens at home. I spend 5 seconds at night to plug in and 5 seconds in the morning to unplug and have a full battery with over 200 miles of range, all in the comfort of my garage. I never have to set foot in a service station and only need to charge for long-distance travel. http://www.teslamotors.com/sup...

Hyundai has a new FC car out that I can lease today. The Toyota Mirai is coming soon. show me a worthwhile EV car that's not a $90k space ship.

Those cars are very heavily subsidized. They cost far more to build than what they're charging. For $57K the Mirai is a mediocre car. There's no way anyone would pay the true cost of the Mirai. They're also only selling 700 cars next year. Tesla sells far more cars than that every week with plans in 3 years to make 500K cars per year. There's also a reason why they subsidize the cost of the hydrogen because right now it's the equivalent of $5/gallon of gasoline.

They will never sell given that the cost of hydrogen will always be significantly higher than gasoline while being less green to boot

costs are on track to drop below gasoline on a per-mile basis. There are many H2 pathways that are very green and these are being scaled up rapidly. Also remember that FC cars are much more efficient than gasoline cars, so any metric has to be on a per-mile basis.

Bullshit. The cost of hydrogen right now is very heavily subsidized. It can't be made cost competitive with gasoline. It is far too energy intensive to make it. You can't transport it to service stations like you can gasoline since the volume of hydrogen required is much larger and the tanks must be much smaller and heavier due to the extremely high pressures involved. Those narrow tanks have a wall thickness of about an inch so they're also quite heavy. It pretty much must be made on-site and that is expensive to do and energy intensive. Making hydrogen from methane is a very mature technology and there's not much room left to cut costs. It is far more expensive than gasoline.

Making hydrogen from water is and always will be cost prohibitive due to the enormous amount of electricity required no matter the catalyst and fuel cell efficiency in a vehicle is maybe at best 60% efficient. Hell, it takes 20% of the energy contained in the hydrogen just to compress it to 5000PSI.

depends where you are. in the PNW electricity prices are 3.5 cents / kwh. if you're smart you can play all sorts of load-balancing and green credit games to get prices down really low. As a benchmarks, it is 60 kwh to make a kg of H2, including compression.

60KWh will get an electric car 200 miles or more. A HFC car will only go a fraction of that. Most places don't have electricity anywhere near that cheap. In my area the cost is closer to $.20-$.30/kwh. The best wholesale rate you might get is $0.10-$0.12/KWh, nowhere close to $0.035/KWh. Right now making hydrogen from water is the equivalent of $6-$11/gallon of gasoline assuming economies of scale which currently does not exist.

You can't transport hydrogen over regular pipelines and you can't economically transport it by truck like gasoline.

There are plenty of H2 pipelines. also plenty of tube trailer trucks. The people who move H2 all around the country think it's viable cuz they do it.

Tube trailer trucks can't transport all that much hydrogen, certainly far less than a gasoline truck can carry. There also aren't very many of them capable of transporting hydrogen. They are also extremely heavy due to the very high pressures involved and the very thick tanks. Hydrogen is a very low density energy carrier. There are very few H2 pipelines. You can't just convert a natural gas pipeline to transport hydrogen. Hydrogen embrittles metal and will leak at the joints unlike most liquids or gases. Electricity, by comparison, is trivial to transport with the infrastructure largely in place.

There's still also a lot of unknowns about fuel cells like how long the PEM membranes will actually last and how they'll hold up in various climates.

20 fuel cell buses ran in Vancouver for 3 years. 5 fuel cell buses run in palm springs. it's much more viable than batteries. also, FC's have the power needed to do some heavy-duty HVAC, while it destroys the range of a battery vehicle to turn the AC on.

3 years is nothing. A typical car should last at least 10 years. Also, how do they hold up in places like Montana where it gets quite cold, especially with the byproduct being water which tends to freeze? Also, the AC doesn't destroy the range of the battery like you claim. In fact, it would have exactly the same impact on range with a HFC vehicle as it does for a battery electric vehicle. I barely noticed the impact of the AC when I drove up to Lake Tahoe and it was 106F in the central valley, and that's with the AC set to a comfortable 72F. Fuel cells degrade. State of the art fuel cells lose 10% of their performance after 2,500 hours under ideal conditions. There are already Teslas that have surpassed that by a fair amount with far less degradation of their batteries. Also, those hydrogen tanks have a limited lifetime and need to be replaced.

Hell, they've already had one hydrogen fire at the hydrogen filling station in my county for buses, and that isn't used by the general public.

the AC Transit leak should have been NBD. all they have to do is open a valve and let the H2 bleed out. it was a bfd because the fire department wasn't trained on what to do and they had a shizz fit and treated it like a big hazard. What everybody learned from this is to make sure your first responders are properly trained.

That may be, but given how easily hydrogen leaks and ignites compared to gasoline fires will be a serious safety issue, especially if any serious amount of hydrogen is stored on-site. Hydrogen is far more flammable than gasoline. It also will leak. Hydrogen is very hard to contain. It seeps through just about anything. It embrittles metal. Gasoline is trivial to deal with by comparison. Now what do you think will happen with a hydrogen filling station with joe public compared to one dedicated to buses?

Fuel cells are still costly to build and still require platinum and there's a lot of additional complexity as well.

prices are down 8x and there's plenty of room to keep improving. it's an area of continuing fundamental research.

They're still not there yet and have a long way to go. They are still far more expensive than batteries and batteries have far more potential to drop in price.

HFCs will never come anywhere close to the cost of an EV. The true cost of the Toyota fuel cell car is likely over double what they're asking and the car they're selling is mediocre at best.

it's clear you know nothing about the cost or the performance of the mirai, so you should refrain from making uneducated statements.

I think it is you who needs an education. The true cost of the Mirai is not $60K. It is significantly higher, especially given that they're only selling 700 of them next year. The performance of the car is also quite mediocre, especially for a car in its price range. 0-60 in 9 seconds is barely better than a Prius. Also, you are far more limited than you are with even a Leaf since there are so few places you can actually drive it. I have a friend with a Leaf who is planning a drive from the Bay Area to Vancouver. It will take him a while, but he can do it. With my Tesla it's far easier since the infrastructure is in place. Today I can drive across the country, along the entire west coast and east coast using superchargers. By the end of next year most the major routes across the country will be covered. http://www.teslamotors.com/sup...

Tesla is building out their network very rapidly and soon others will be following. Tesla's also using grid storage to even out the load to significantly reduce their peak demand.

nobody cares what tesla does. they're a boutique company selling the fantasy of owning a spaceship car. live in the real world not your fantasy world.

Then why is everyone trying to copy them, like BMW, Audi, GM and Nissan? The other car companies definitely took notice. When Tesla releases their $35K car with a 200+ mile range in a few years it will be game over for fuel cells. BMW is also planning to build out their own rapid charging network to catch up with ChaDeMo. Their so-called 'boutique' car is outselling the gasoline equivalent luxury cars.

In a couple weeks Tesla will be starting their battery swapping. Once that goes in then the last advantage of hydrogen fuel cells is over.

loooool battery swapping is doa and will never happen. battery companies are only fake pursuing it as a canard to have a bullet point argument against other fuels.

The first battery swapping station opens in two weeks. The cost of a battery swap will be significantly cheaper than an unsubsidized fill-up of Hydrogen and take less time.

Hydrogen filling stations will require that the hydrogen be made on-site since you can't effectively transport it.

so? then make it on site. there are many technologies to do so.

All of those technologies are also rather expensive to implement. The cheapest method is quite mature and still far more expensive than gasoline.

http://www.thenewatlantis.com/... [thenewatlantis.com], while a bit dated is still a good description of the issues involved with hydrogen.

dated article is dated. technology moves on.

in short, instead of hating on other things you should quietly reflect on why you have such a nasty reaction against anything that's new. what other promising technologies do you reject out of hand for no real reason?

http://cleantechnica.com/2014/... is another good article on fuel cells and their true cost and is much more up to date. Many of the points in the article have not changed since you can't change the laws of physics.

I'm just saying that the actual physics and chemistry makes hydrogen an expensive dead end. The infrastructure for EVs is years ahead of fuel cells. All you need is electricity. You also need far more hydrogen filling stations than you do rapid chargers. A rapid charger is only needed for long distance travel whereas a hydrogen filling station is needed for all HFC cars. Most EVs charge overnight and it takes only a few seconds to plug in and unplug.

The cost to build a nationwide supercharger network able to handle all of the nation's long distance passenger vehicle travel would be around $4B. The cost of building out the required hydrogen infrastructure is around $500B. Within three years Tesla will have cut their price of batteries by at least 30% There is still tremendous room for improvement for batteries, for cost, capacity and performance with no end in sight. HFCs are an expensive dead end technology.

Toyota is planning on selling tens of thousands of fuel cell vehicles by 2020. Tesla is selling that today. By 2020 Tesla will be selling at least 500,000 cars a year. In the long run battery electric vehicles just make a lot more sense. They will be far cheaper to operate and have far more infrastructure already in place. EVs will also be far cheaper to build and far simpler than a HFC vehicle. EV charging stations are going in everywhere and even rapid chargers are quickly building out. By the time hydrogen stations are able to handle a few cities and maybe a few thousand cars, Tesla will have most of the country covered. Tesla's also not alone in that. Companies like eVgo, Chargepoint, Blink, etc. are all building out networks as well. Then you have companies like BMW partnering with eVgo to build out their rapid charging network, which Tesla should also be able to easily support since only their physical connector is different.

Modeling paged and segmented memories is tricky business. -- P.J. Denning