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New Semiconductor Could Improve Vehicle Fuel Economy By 10 Percent
cartechboy writes: "Automakers are scrambling to increase vehicle fuel economy every year as regulations increase, so when an automaker finds a way to possibly increase fuel economy by 10 percent with one new part, that gets some attention. Today that automaker is Toyota, and the part is a new semiconductor. Toyota's power control units (PCU) in its hybrids use semiconductors to govern the flow of electricity between the battery and the electric motor. Unfortunately, they're also an electrically restrictive component. Toyota says the PCU accounts for a quarter of the total electrical power losses in a hybrid drive system, and semiconductors alone make up a full fifth of the total. Reduce electrical losses through a semiconductor, and you can make your hybrid system (and therefore your car) more efficient. Toyota has done this, in theory at least, using a new silicon carbide material for its semiconductors, rather than a standard silicon unit. The future could be shaped by individual parts, and this new semiconductor tech is one piece of that puzzle."
Are these SiCFETS with lower R(on), or improved SiC IGBTs, or what?
I wouldn't think so, because silicon carbide transistors isn't brand spanking new, unless you count a few years old as new.
My favorite local semiconductor manufacturer produces SiC wafers (and power components), and has seen a nice stock-price bump over the last day or two. Wonder if it's related to this news?
"The future could be shaped by individual parts, and this new semiconductor tech is one piece of that puzzle.""
Apart for the fact that this new semiconductor tech isn't an individual part, then sure.
No one has a right to their *own* opinion. They have a right to the TRUTH.
All that verbiage to say nothing except "Toyota" and SiC.
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
Also driving slower, not driving full throttle and hard braking to a stop light/sign, etc.
I used to have an 2008 MkV Jetta with the 2.5L gasoline engine. The government said I should be getting 21/29mpg city/highway. My best was 46 mpg driving from Sacramento to San Diego. Now I have a Prius V, and I get better gas mileage than that without even trying.
The summary makes it sound more like electricity economy.
The article isn't any better. It is so badly written that I can't really tell what they are trying to say. I think they have reduced electrical losses by 10%, which is totally different from increasing efficiency by 10%. I believe that most electric vehicles are already over 90% efficient, so increasing that by 10% would be almost impossible.
How is this news? SiC semiconductors including Schottky diodes, JFETs and MOSFETs have been commercially available since 2008. My first design to use SiC JFETs and diodes was in solar power inverter developed back in 2009 (and yes the RDSon and revers recovery times are indeed exceptional). Stay tuned for: "Toyota discovers wonder metal by adding carbon to iron"
You know what else increases fuel economy? Not driving everywhere.
As driving gets better and cheaper, people drive more. It's not surprising - driving has benefits and gives people pleasure, either directly or indirectly. If it costs $2 to drive to the beach, I go in a heartbeat. If it costs $200 I stay home.
Improving the human condition is great, but just don't expect improved MPG to do much for overall fuel consumption outside of commuting (where group options may be better anyway).
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Also driving slower, not driving full throttle and hard braking to a stop light/sign, etc.
Or you could just buy a diesel.
I used to have an 2008 MkV Jetta with the 2.5L gasoline engine. The government said I should be getting 21/29mpg city/highway. My best was 46 mpg driving from Sacramento to San Diego. Now I have a Prius V, and I get better gas mileage than that without even trying.
I bought my wife a 2012 Jetta TDI, and she regularly gets 45-50 MPG, even with her lead foot. But even our old gas Jetta was getting somewhere in the range of 25-35.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Buses take longer. There's only so much time per day, if you spend it waiting for buses, you get less done.
10%+ increase in efficiency gets automakers' attention? No it doesn't.
If they were really serious about fuel economy, they'd go to work on the aerdynamics for starters. Current vehicles have far too much air resistance. And actually they know this. They don't improve the aerodynamics for several reasons. They're afraid the public will think it ugly, and they think it will cost more to manufacture. One of the simplest improvements are skirts for the rear wheels. Every time it's been tried, the public rejects it. Another easy improvement is smoothing the underside. But that costs more, and not just during manufacturing. It also increases maintenance costs as it's one more item that has to be removed to service much of the car.
Intellectual Property is a monopolistic, selfish, and defective concept. It is "tyranny over the mind of man"
You have to factor in time, as well. I *do* walk and take public transportation, when the combination of effort, time and money one of those options costs seems nicer than driving - for instance, driving into downtown LA, is a lot faster than taking the light rail if there isn't traffic, but there's usually traffic, plus then when you get there you have the immense fun of finding parking. So it's often (not always) nicer taking the train, so I do. On the other hand, I tried taking the bus once across town. It's pretty cheap, but it takes bloody forever, so it's unlikely I'll ever try that particular experiment again, given that taking a car across town is far more convenient. If public transportation were more convenient, I imagine people would use it more. (That's not particularly insightful, though; seems pretty obvious, really.)
lol, I am always amazed how many people pass me as we approach a red light. Is buying brake pads a fun experience I have been missing out on?
Electric vehicles are nowhere near 90% efficient. Keep in mind this includes more than the electric motor efficiency (some electric motors may be 90% efficient.)
It's not as big a deal as they're making it out to be, really. It's got a lower 'on' resistance. Similar reductions in power lost to waste heat could be accomplished by using more MOSFETs in parallel. Don't get me wrong, it's a useful development, but it's not earth-shaking news either.
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
That's why CREE are the only ones who make white LED's on silicon carbide.
The problem with diesel cars in the USA is that they're more expensive than current hybrids (particularly the Prius) and diesel fuel is on average more expensive at the pump than 87 octane gasoline.
Took me a sec to decipher that too. I think the PCU statement is irrelevant and they cut the losses in half. Perhaps the connectors in the PCU cost 5% thus 25% instead of 20%
Overall rather light on actual info and a little heavy on the headline. We don't have a good substitute for 'fuel economy'. "Increases eMPG" I suppose is the most accurate but sounds kinda strained.
Well, the products do have to sell, and as you point out they have tried.
Given that rear-view cameras are soon mandatory, some automakers have asked to replace side mirrors with cameras, too. Maybe the public won't reject this and it will greatly help with aerodynamics.
It doesn't hurt to be nice.
You can put it in your hybrid and all-electric cars and boost your fleet fuel economy, which is what these automakers are graded on. The summary left out the important word "fleet".
It doesn't hurt to be nice.
Yep. Unlike aircraft, there just isn't a significant desire by the auto manufacturers to really get serious about drag reduction. It's really a shame too since things like wheel skirts are really simple.
I think part of the problem is that they intentionally put them on the most unconventional looking cars just to help ensure they don't sell because people are hesitant to significant change. I'd rather they step up and tell people how much fuel that would save with them on and what that would cost annually. And have it as a package you can put on at the dealership.
Most electric motors above 125hp have a "Minimum Nominal Efficiency" of 92% and higher. According to this quick Google result: http://www.engineeringtoolbox....
The problem with diesel cars in the USA is that they're more expensive than current hybrids (particularly the Prius)
The hell they are:
2014 Jetta TDI Value Edition: $21,295
2014 Beetle TDI: $24,595
2014 Chevy Cruze Diesel (no options): $24,310
2014 Prius Base Model: $24,200
Seems to be just about the same to me, save the Jetta; mine was a bit more (~$28,000), but that's because I sprung for every option except satnav. Seems the real problem is lack of options, unless you're a VW or Chevy fan.
diesel fuel is on average more expensive at the pump than 87 octane gasoline.
Yea, but you get almost-if-not-more-than twice the miles out of the same amount of fuel, so it ends up being a net win. I will concede that the sticker shock of diesel fuel does cause a lot of people's brains to shut off, and thus, not see the benefit.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Jevons’ paradox.
On the other hand, you can get diesel for SUVs or trucks, so if you need one of those diesel is often your most fuel-efficient option.
It doesn't hurt to be nice.
Battery efficiency is not the same as fuel efficiency.
I've got better things to do tonight than die.
100% of the losses are "the total losses"
25% of the total losses are in the PCU
20% of the total losses are in the semiconductors. The summary repeats the word "total" to clarify this, but you misread the summary as 20% of PCU losses are semiconductor (or 5% of total) which is not correct.
If 20% of the total losses are in the semiconductors, and the new ones have half as much loss, then the net result is the elimination of 10% of the existing total losses.
It doesn't hurt to be nice.
You must live in an area with shitty public transportation, then, if so few people are using it. In the SF Bay area, buses and trains are commonly standing-room-only during the day.
APK quotes people (including myself) without context and should not be trusted. Just thought you should know.
I prefer mp4...
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Diesel cars have much better mileage, more torque and diesel engines normally last longer than regular cars.
but I agree hybrids are better for city use.
I've got better things to do tonight than die.
This is not the same as the vehicle's overall efficiency. Batteries and drivetrains are nowhere near 90% efficient.
Tesla claims an overall efficiency of 88% for their cars, from grid to wheels.
Any hard numbers on how much skirts would help? Because when I check how much "opening windows @ 55mph" vs "closed windows" affects my mileage, I cannot find any measurable difference (as measured my an OBD2 scanner). I get the impression that there just arent that many significant gains to be had in aerodynamics.
This is pretty interesting, but it's not clear exactly what that 88% represents. I'm not sure what "overall drive efficiency" is. They put a picture above the 88% figure that has elements that probably aren't in the "drive efficiency" number -- misleading at best. It probably doesn't count the grid->battery efficiency (why else would they include the word "drive"?)
Go back to 4chan, kid.
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
I'm waiting for someone to make the Mythbuster's Dimpled Car. They got nearly 10% better MPG in their test.
If you let the smoke out...
oh, never mind.
I've fallen off your lawn, and I can't get up.
Looks like Toyota has produced the pinch-channel Class I V transistor in SiC with no minimum offset / gain.
Seriously, holy grail for current steering.
Can't find the vendor of the raw SiC so no idea about Delta-V / Delta-I limits but looks very good
10% net reduction in loss.
I just recently checked bus prices, and I got to the destination several times faster driving, on $20 in gasoline, versus a $40 bus ticket.
Prices serve as a very good proxy for efficiency... Based on prices, I do not believe that buses are more efficient for short to medium trips in the US.
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I forgot a significant detail... That's $20 in fuel for the ROUND TRIP, while the $40 ticket price was one-way, and not just took longer, but required substantial travel by foot to reach the destination from the nearest station.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
The benefits in the modest increase in efficiency are not so much from reduced energy usage, but the higher efficiency reduces the amount of waste heat that has to be removed from the PCU. The higher junction temperatures allowable with SiC makes the cooling task even easier. What has Toyota excited is that the PCU with SiC is much smaller than the PCU with standard silicon power devices.
A Shadeless room is a brighter room.
It's even better when they're completely wrong.
MOSFETs have no fixed voltage drop, just a resistance. Paralleling them indeed reduces the resistance, and hence losses and drop.
The d-bag GP is thinking of BJTs ("normal" transistors), which do have a more or less fixed voltage drop (it varies somewhat with current and temperature).
Sent from my PDP-11
Here are some hard numbers: the Aerocivic. With home made modifications to the shape, this guy doubled the fuel economy of an ordinary Honda Civic, from its pretty good factory rating of about 47 mpg to 95 mpg.
Intellectual Property is a monopolistic, selfish, and defective concept. It is "tyranny over the mind of man"
In a hybrid, improved electrical economy is improved fuel economy.
Which appears to be an odd "only in America" thing. The stuff is cheaper to make at the refinery.
Yes, dimples work. Dimples are one kind of vortex generator. But, a golf ball has to have dimples all over it because it tumbles. On a car, vortex generators are best on trailing edges only. Likely Mythbusters would have gotten even better fuel economy if they'd used dimples only in the right places. The Corbin Motors Sparrow had some. There are also vortex generators intended to be added to the sides and tops of truck trailers, at the rear edge.
Intellectual Property is a monopolistic, selfish, and defective concept. It is "tyranny over the mind of man"
Meanwhile in China alone there are millions of counter examples a day that laugh at your outlier. Still sucks to be hit for that much for a ticket though.
A 150-year old observation about markets and business production does not apply to individuals spending money to reduce consumption. Sure, a few people who overspend to get a more fuel-efficient car will maintain their gasoline budget and take extra trips in it, but far more will take the money saved on fuel and spend it on other things. Sure, those things have their own energy costs, but a fancy Apple gizmo has far less embodied energy than the gasoline the owner saved. Besides, those wacky environmentalists spending $$$ to consume less energy are likely to spend some of the money saved on additional energy-saving measures.
Read the Wikipedia article more carefully, there are so many caveats and non-linearities that it really is a weak argument even before you consider individual consumers' motivations.
=S
My example isn't an outliers, it's typical pricing. And pricing in China has no relevance at all. In the US, bus travel is incredibly inefficient.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
I don't know where they get the "10%" from.
TFS states:
1. "Toyota's power control units (PCU) in its hybrids use semiconductors to govern the flow of electricity between the battery and the electric motor."
2. "Toyota says the PCU accounts for a quarter of the total electrical power losses in a hybrid drive system, and semiconductors alone make up a full fifth of the total."
So, "a quarter" = 25%, and 1/5 of 25% is....5%
Sleep your way to a whiter smile...date a dentist!
Globally the consequence of extreme price gouging you are seeing locally is an exception instead of the rule. Using it to suggest that public transport is always a bad idea is either stupid or dishonest.
With the benefit of more noise, carcinogens, soot and NOx.
The Kruger Dunning explains most post on
Interesting. My friends in former eastern block countries love american off road vehicles as then seem to be the only ones the last in ares where the roads aren't good.
The Kruger Dunning explains most post on
Buss are the least environmentally friendly thing you can take.
By a long shot.
If everyone on a bus instead drove a car that got greater then 19MPG, less gas would be used overall and a hell of a lot less emissions.
Buss where designed so the poor people can get to work.
That was their purpose. No being environmentally friendly, or quicker, or convenient.
The Kruger Dunning explains most post on
buss that aren't standing room only lose money. But if you cross the price point, no one uses them. Would you pay 15 bucks a trip? Just to sit on a buss that is far worse for the environment then any car sold today? If you are concerned about money and the environment, you should be driving a 3 cylinder car.
I have no idea why you are making this about political ideology. It's really just math.
Buss cost more and pollute more. far more, then cars.
The Kruger Dunning explains most post on
The numbers you quote aren't quite right (his highway mileage with 10% ethanol gas is mid-60s), and he also replaced the engine to get some of that improvement. But overall it seems he did reduce wind drag by a lot. Boxy SUVs are especially bad in that regard.
Only because public transport sucks where you live. In Tokyo it is often faster than taking your own car. Buses and trains come every few minutes, and the time you spend waiting is more than made up for by avoid the traffic jams, parking and filling your car up every now and then.
You get more done because the time you spend travelling is not wasted controlling a car. You can browse the net on your phone, post to Slashdot and answer emails, play games or just relax.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
They couldn't dimple the entire car body for safety reasons, unfortunately. The bonnet (er... hood) in particular has to be fairly flexible and smooth that if you hit a pedestrian their skull isn't smashed when their head hits it. Maybe the doors and roof would be okay though.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
88% efficiency means that out of every 1KWt*hr you pull from your outlet, 0.88KWt*Hr will be used to propel the car. And it's the TOTAL efficiency, including the battery charging overhead.
I have a Chevy Volt with 10.5KWt*hr of battery storage, it takes about 11.2KWt*Hr to charge it completely. So we're talking about ~5% loss during the charging. With other losses in the high-voltage system, the 88% figure seems believable.
The ones that make it for export are things like Jeeps and not the wide variety of piece of shit fake offroad vehicles designed to make their buyers feel tough, so long as they never dare to get dirt on it.
Jeeps can come with diesel. They are built for a practical and not cosmetic purpose.
I thought the POS label would be enough for people to work it out that I am describing the utter lemons and not every thing on the road.
Air resistance isn't a major issue until you hit about 45mph. The vast majority of the world's motoring fleet spends the vast majority of its time well below that speed (which isn't to say the gains aren't worthwhile above that speed, but there are better targets to aim for)
Modifications which improve efficiency at low speeds and in stop-start traffic have the greatest overall effect.
Because this was never about the USA in the first place but about fuel economy and public transport costs. You shifted that goalpost yourself for some reason that is unclear and IMHO totally irrelevant to the discussion.
Besides, while it may be true NOW in the US where your bus company has a local government mandated monopoly it was not true in the past when there were multiple purely commercial bus companies.
Circumstances are changing. The way our road system and automobiles work now, yes, efficiency at low speeds is more important. But improvements to combustion engines won't amount to much if we all end up switching to electric cars as I think likely in the next few decades. However, aerodynamics will still be important. Going electric will address the issue of low speed efficiency so well that we'll have to look elsewhere for improvements. Being able to shut down while waiting at a red light is a huge gain, and electric motors can handle that easily.
Another definite possibility is switching to driverless cars, and the removal of all traffic lights as such cars would coordinate so well with each other that lights would no longer be needed. We'd be traveling around faster, and that would of course make aerodynamics more important.
Only way aerodynamics won't matter is if we travel in a vacuum, and that's not too likely any time soon. Can't see the gains of enclosing a highway in an airtight tube and pumping out all the air as ever more than the costs of building and maintaining it and equipping cars with pressurized cabins and fresh air. Might compromise and go with reduced air pressure, but then aerodynamics would still matter.
Intellectual Property is a monopolistic, selfish, and defective concept. It is "tyranny over the mind of man"
Yea, because the processes of mining rare-earth minerals and converting them into batteries is so clean and environmentally friendly.
An enigma, wrapped in a riddle, shrouded in bacon and cheese
Instead of a Union, the Japanese have a corporate Lord who directs everything for the benefit of said Lord, like workers living 7 to a bungalow, sleeping under desks (normal behavior), mandatory FREE overtime.
Small investors ripped off via Land-value swaps and Mafia style Keiritsu,
Capitalism without remorse.
Otherwise known as Mafia
hmm, sounds like a piece of Koch Brother's Wet Dream America