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Duane Benson
Not to make things any more complicated than they already are, but again, if the ...
nicolas.mokhoff
Duane: you make rational arguments. What do you think about Obama's plan? "The ...
Cleantech vehicles’ dirty little secret: Powersource issues
Rick Merritt
6/17/2011 1:15 PM EDT
Chips’ role
Onboard chargers today are typically limited to relatively slow and small 3.3or 6.6kW devices that take hours to charge a car battery. Larger, 15to 20kW dc chargers are fast but are still too bulky and risky to put in the car itself and are instead being built into external units for use in the garage at home, said Ford’s Scholer.
To prevent overheating and fires, the charging and discharging of each cell in a large lithium-ion battery pack needs to be carefully supervised. "We are looking into chips for that, but there's nothing in production today," said Cherif Assad, a marketing manager for power train and hybrid vehicle components at Freescale Semiconductor.
The company earlier this year announced low-voltage battery controllers targeted at the microhybrids or for use in regenerative braking, wherein the power generated from stopping is used to help charge a battery or ultracapacitor. Thus far, however, most of the circuits used for chargers in plug-in vehicles are off-thes-helf industrial parts that are modified for automotive use.
Separately, hybrids require pre-driver and controller circuits to drive 30to 120kW electric motors. Freescale and Fuji Electric struck a partnership to design parts using slim inverters that can be integrated with mechanical modules and their cooling systems. The new components must drive up efficiency from about 35 percent for today's parts to more than 90 percent, Assad said.
"Inverters have never been the subject of much attention for how you improve performance, size and weight," said Dan Viza, director of corporate strategy and business development at Freescale. "Initial implementations are using available industrial components, but we will soon see the first purpose-built semiconductors for inverters and charging units."
Transmission specialist ZF Friedrichshafen and BMW launched a research project earlier this year to create an integrated solution for hybrid-vehicle components, aiming to integrate control and power electronics to simplify production and servicing of hybrids. Infineon and passive component maker Kemet are taking part in the project. The integration will require work on new cooling concepts so components can tolerate the high temperatures inside the transmission. The resulting design promises to reduce cabling and simplify system interfaces.
The overall electrical architecture of a hybrid or electric car is "totally different" from what has existed before, posing problems of EMC compliance with 650V signals and 400amp switches, said Assad of Freescale. That implies new kinds of high-voltage interfaces for converters, inverters and controllers that monitor the power signals, he said.
Standards, especially for chargers, are also needed, and pursuing them has become a full-time job for Scholer of Ford. "We started with EV standards 20 years ago, and now we’re updating them for plug-in hybrids and starting work on fuel cell standards," Scholer said. "We have been working on SAE standards for about three years and are in the implementation phase with some of them, but we are going to be working on the standards for another three to five years until we get everything done." Multiple standards groups are working in parallel with research demonstration projects and live deployments, he said.
The efforts include protocols such as supporting fast charging over dc. Smart Energy Profile 2.0, for communicating rate information over power lines to utilities, as well as specifications supporting fast charging over dc.
One proponent of the latter, ECOtality, is said to be gearing up with help from the U.S. Department of Energy to install as many as 1,300 public charging stations in California, Oregon, Tennessee, Washington and other states. The plan includes about 350 fast-charging stations.
"Carmakers know how to control an onboard charger, but there are more things to control with offboard controllers," said Scholer.
Initial draft standards for fast chargers are now up for an initial ballot, but once systems are deployed engineers will learn more about their behavior.
"We will have changes as we start implementing," Scholer said.
More from this article and other articles can be found in the Special digital edition on Automotive Intelligence.
Onboard chargers today are typically limited to relatively slow and small 3.3or 6.6kW devices that take hours to charge a car battery. Larger, 15to 20kW dc chargers are fast but are still too bulky and risky to put in the car itself and are instead being built into external units for use in the garage at home, said Ford’s Scholer.
To prevent overheating and fires, the charging and discharging of each cell in a large lithium-ion battery pack needs to be carefully supervised. "We are looking into chips for that, but there's nothing in production today," said Cherif Assad, a marketing manager for power train and hybrid vehicle components at Freescale Semiconductor.
The company earlier this year announced low-voltage battery controllers targeted at the microhybrids or for use in regenerative braking, wherein the power generated from stopping is used to help charge a battery or ultracapacitor. Thus far, however, most of the circuits used for chargers in plug-in vehicles are off-thes-helf industrial parts that are modified for automotive use.
Separately, hybrids require pre-driver and controller circuits to drive 30to 120kW electric motors. Freescale and Fuji Electric struck a partnership to design parts using slim inverters that can be integrated with mechanical modules and their cooling systems. The new components must drive up efficiency from about 35 percent for today's parts to more than 90 percent, Assad said.
"Inverters have never been the subject of much attention for how you improve performance, size and weight," said Dan Viza, director of corporate strategy and business development at Freescale. "Initial implementations are using available industrial components, but we will soon see the first purpose-built semiconductors for inverters and charging units."
Transmission specialist ZF Friedrichshafen and BMW launched a research project earlier this year to create an integrated solution for hybrid-vehicle components, aiming to integrate control and power electronics to simplify production and servicing of hybrids. Infineon and passive component maker Kemet are taking part in the project. The integration will require work on new cooling concepts so components can tolerate the high temperatures inside the transmission. The resulting design promises to reduce cabling and simplify system interfaces.
The overall electrical architecture of a hybrid or electric car is "totally different" from what has existed before, posing problems of EMC compliance with 650V signals and 400amp switches, said Assad of Freescale. That implies new kinds of high-voltage interfaces for converters, inverters and controllers that monitor the power signals, he said.
Standards, especially for chargers, are also needed, and pursuing them has become a full-time job for Scholer of Ford. "We started with EV standards 20 years ago, and now we’re updating them for plug-in hybrids and starting work on fuel cell standards," Scholer said. "We have been working on SAE standards for about three years and are in the implementation phase with some of them, but we are going to be working on the standards for another three to five years until we get everything done." Multiple standards groups are working in parallel with research demonstration projects and live deployments, he said.
The efforts include protocols such as supporting fast charging over dc. Smart Energy Profile 2.0, for communicating rate information over power lines to utilities, as well as specifications supporting fast charging over dc.
One proponent of the latter, ECOtality, is said to be gearing up with help from the U.S. Department of Energy to install as many as 1,300 public charging stations in California, Oregon, Tennessee, Washington and other states. The plan includes about 350 fast-charging stations.
"Carmakers know how to control an onboard charger, but there are more things to control with offboard controllers," said Scholer.
Initial draft standards for fast chargers are now up for an initial ballot, but once systems are deployed engineers will learn more about their behavior.
"We will have changes as we start implementing," Scholer said.
More from this article and other articles can be found in the Special digital edition on Automotive Intelligence.
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Lee Harrison
6/17/2011 4:32 PM EDT
Unfortunately this commentary is too superficial, and too focussed on a very short-term view of the issues.
In the near term it is pretty obvious that there will not be a large-scale migration away from internal combustion (IC) engines powered by petrochemicals: the costs of changeover are large all through the production and life-cycles of both the automotive and petroleum industries.
Longer-term though, everything changes and so the whole issue is predicting at what rate new technologies can "penetrate" ... and the reality of that issue depends in part on technology, in part on taxation policies, and in part on a population of "early adopters" who choose new technologies for reasons which are beyond minimizing their costs.
I'm very skeptical that these "gurus" you cite know anything more than any other reasonably-knowledgeable observer about the relevant (and hard to forecast) issues which will drive the market.
One very pointed comment in this regard: about 18 months ago there were two separate economic analyses of electric vehicles which came to the conclusion that "they would never be economic unless gasoline was over $4 per gal. At that time such a cost was seen as far in the future.
Bought a tank of gas recently?
And the economic cross-over point is somewhat less already because battery technology has moved forward since then, and those analyses were conservative.
The major issues facing EVs right now in terms of economic attractiveness are in part amenable to manufacturing scale, but also involve issues of what fraction of cars/users can live with their charging time limitations, and what societal adaptations could/would be made to accommodate them.
And of course, technological improvements may ease these issues too.
The one thing I would say -- when a guy says "I'm not counting out .... lead acid" ... I know that I know more than he does.
I guarantee you -- the energy storage solution for future vehicles will not be lead acid.
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DrQuine
6/17/2011 4:42 PM EDT
The hybrid / PHEV development initiatives are paying dividends in several ways. First, the stop / start technologies save energy with modest investment. Second, the regenerative braking not only recovers energy, it also spares the brakes. My 91,000 mile Honda Civic Hybrid still has more than 50% of the original brakes remaining (I used to get 30,000 miles per set). With a lifetime average of 49.2 mpg, the additional cost of the car was paid back in less than 3 years - not including the repair cost savings. If the gas guzzlers could utilize these features, the savings could be substantial. Purely electric powered short drives will be a further benefit.
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selinz
6/17/2011 4:57 PM EDT
The other thing that most people forget is that most of the energy comes from coal and petro plants. By the time the electrons are delivered to your car, are you better off? DrQuine makes a good point about generating "free" energy going down hills and braking. I too have a civic hybrid (160K+ miles on my 2007)and I figure that I've saved over $12K in gas, compared to the 23mpg car I was driving. (3500 gallons at ~ $3.5/gallon). I will say that DrQuine must be driving like a grandmother to be averaging greater than 49mpg with a Civic Hyb! ;-)
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goafrit
6/17/2011 8:25 PM EDT
It is dead right. They are riding on subsidies but very soon the country will hedge on debts that this industry will crash.
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prabhakar_deosthali
6/18/2011 7:07 AM EDT
One simple ( weird ?) thought. If we can develop a road network with DC rails from which the cars can directly tap the electricity ( like electric trains ) then all those issues related to battery weight , recharge time , battery life, fire hazard all those will just go away. Why not think on this idea?
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PJames
6/20/2011 8:23 PM EDT
I thought about it... kinda scary.
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daleste
6/18/2011 4:09 PM EDT
$10,000 for the battery? Has anyone had to replace the battery in their EV or Hybrid? Can you tell us what the cost is? That would take selinz' savings from 12K to 2K real quick.
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seaEE
6/19/2011 1:49 AM EDT
If a large number of drivers switch from gas to electric, how will this increased demand for electricity affect the price of electricity?
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PJames
6/20/2011 8:27 PM EDT
Probably depends a bit on where you live. Just recently saw that they are giving away electricity at night in the Pacific Northwest. Too much water in the reservoirs and forced to run through turbines generating electricity no one needs. Wind farms are complaining because they've been forced to shut down at times.
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Lee Harrison
6/19/2011 11:23 AM EDT
No one expects electric cars to dominate the automotive fleet any time soon.
At moderate fractions, charging electric vehicles (at night) will not impact electric power generation capacity (peak demands are always summer daytime), and potentially may even REDUCE the cost of electricity slightly for many customers by improving the generation utilization capacity.
At the moment almost 3/4s of US electricity is generated by coal + nuclear power. Almost none is generated burning oil.
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hm
6/19/2011 11:50 AM EDT
These are wonderful engineering challenges and opportunities for designing most accepted hybrids and PHEV vehicles. Major breakthorugh for battery technology or power and cotrol devices looks to be very close and soon we will have wonder EE vehicle.
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Steve Rose (Maui)
6/20/2011 6:55 PM EDT
We drive three hybrid vehicles. The first was purchased more than ten years ago. We have used photovoltaic energy for 35 years. We live on an island with a very small, isolated grid, so we see grid related issues much earlier.
At present, electric-only cars degrade the environment as SELinz points out (especially here, where the utility has an EPA exemption to burn high sulphur fuel). Our hybrids have "super ultra low" emission engines, and are cleaner at generating energy than the utility.
The utility also has to keep a gas turbine running 24/7 to compensate for a new wind farm, to immediately provide energy during lulls in the wind.
Hybrid vehicles also represent a near ideal source of standby or off-grid power, with the addition of an inverter running from the high voltage battery. The gas engine only runs as needed to maintain the charge on the battery. This suggestion was made to Toyota more than a decade ago, then posted when there was no response (steverose dot com). Had this option been available, some small part of the misery of the quake and tsunami could have been alleviated.
Photovoltaic and wind sources that use the grid as if it were storage are a scam on government subsidies. With our small grid we have already experienced the limit that must be placed on this approach. It occurs well before alternate sources have a significant impact on pollution. The problem is storage, not generation. Storage can be central or local, although central incurs grid losses in both directions.
Aloha, Steve
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Duane Benson
6/22/2011 7:51 PM EDT
When we're questioning the best approach between the different types of hybrid / electric drives, we might want to also question the type of vehicles we should be focusing on.
Let's say the average vehicle is driven 20,000 miles per year. A 12mpg truck or SUV will burn 1,670 gallons of fuel per year. If we increase the mileage, by just 4mpg to 16mpg, the vehicle will only burn 1,250 gallons, or about 400 gallons fewer.
(I picked the numbers because my 1995 truck was rated at 17/15mpg and typically gets about 16. Not long ago I looked at the new version of the same model and it was rated at 12mpg. If you can go down 4mpg in a decade, it shouldn't be tough to go back up)
Next, lets take a 25mpg passenger car. It will burn 800 gallons per year. We would have to double its mileage to 50mpg to reduce fuel consumption by the same 400 gallons.
Given the large number of trucks and SUVs on the road, it seems to me that it would be a lot less expensive to move the pickup and SUV mileage up by four mpg than it would to double the mileage of the 25mpg passenger car.
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nicolas.mokhoff
6/30/2011 3:13 PM EDT
Duane: you make rational arguments. What do you think about Obama's plan? "The Obama administration is considering requiring cars and light trucks to average 56.2 miles per gallon by 2025 — a move that could boost the cost of vehicles by $2,100 or more. Top federal regulators and White House aides disclosed their initial proposal — requiring 5 percent average annual increases in efficiency over an eight-year period — in separate, private meetings this week with Detroit’s Big Three automakers, four people briefed on the matter told The Detroit News."
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Duane Benson
6/30/2011 4:49 PM EDT
Not to make things any more complicated than they already are, but again, if the government is going to mandate fuel mileage increases, it really should look at actual savings rather than just a number that looks nice in the headlines.
Jumping the fleet average up that much will cost a lot of money to reach past the point of diminishing return. Since it's an average, it might not even do much to reduce the total fuel quantity used.
If the mandate were to put minimums based on the class of vehicle, most of the improvement could be focused on the low-mileage set, thus giving the greatest savings.
Mandate that the 1,700 gallon per year SUV become a 1,200 gallon per year SUV. That change could probably be made in software by doing little more than dropping horsepower by a few points. It could even be retrofitted into many currently-on-the-road vehicles at the dealership.
Each mileage range would get a successively smaller improvement mandate. Don't even worry about anything that already gets 40+. It's a waste of money and engineering resources with very little return.
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