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Toyota Unveils Plug-in Hybrid Prius
phlack writes "Toyota has announced a plug-in hybrid vehicle, based on their popular Prius. So far, it will only have a range of 8 miles on the battery (13km). They are going to test this vehicle on the public roads, apparently a first for the industry. From the article: 'Unlike earlier gasoline-electric hybrids, which run on a parallel system twinning battery power and a combustion engine, plug-in cars are designed to enable short trips powered entirely by the electric motor, using a battery that can be charged through an electric socket at home. Many environmental advocates see them as the best available technology to reduce gasoline consumption and global-warming greenhouse gas emissions, but engineers say battery technology is still insufficient to store enough energy for long-distance travel.'"
what is the environmental advantage of electricity for cars ? It's mostly made with fossil fuels. I've never understood this. Am I missing something ?
My round trip to work is 7.5 KM. A little too far to walk or bike (and not be too fragrant for my cow-irkers), but perfect for this little beastie. In fact, even though I live in one of the worlds sprawliest cities, it's still enough to get me one-way somewhere, and I can plug in there for the trip home. I'm sure this would be great for most people and their little jaunts to the grocery store, or to get a movie, or insert the blank here. The majority of driving is short little trips, and this fills the bill.
Of course, I'll still keep my bigger, gas fueled beast for when I have further to go, but this should be a real option for many people.
If I knew the wedgies I gave you back in 6th grade would have resulted in this . . . I might have taken a moments pause.
And where do the batteries get the electricity to go those 2.5 miles?
Oh yeah, you put gas in the tank, and the engine will charge the battery, or you could put gas in the tank and drive it up a hill and brake all the way down. Either way it is powered by gasoline.
Considering there used to be a waiting list to buy a Prius (All models are hybrid, 50MPG), and used cars were selling for the same price as new, but you could walk to your local Honda dealership and buy a Civic Hybrid (48MPG) off the lot, they made the right decision. It is about the type of people who want a Hybrid, they want it to be clear they are driving a Hybrid, the Prius does that while the Civic does not.
Toyota's engineering is very good. Meet the 78MPH-top-speed, 120-miles-per-charge 1997-2003 Toyota RAV4 EV: http://en.wikipedia.org/wiki/Toyota_RAV4_EV. I was passed by one this morning on the freeway, I felt so inferior in my comparatively gas guzzling Prius.
The batteries don't have a long way to go, they've just been forced out of the picture.
Li-Ion batteries are still very expensive, so a Li-Ion Prius would cost at least $10-15K more.
Nimh batteries would be a more cost effective option, and Toyota used them in it's all electric Rav4. Sadly, Chevron now owns the patents and won't let the technology back on the market -- http://www.ev1.org/chevron.htm
The technology for that is there... just have poles like the meter parking with an outlet on it that u swipe a card or whatever then plug in and park and have it charge u for the electricity while you're parked. of course some sort of security would have to be used to keep people from stealing your power but a simple locking mechanism for the plug should do it.
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Trying to fix or change something only guarantees and perpetuates it's existence
1) The jump to electric power is a must, it's cleaner, easier to transport over long distances, and it can be produced many different ways. What we don't have yet, is a great way to store electricity in medium-sized quantities efficiently. Batteries just simply won't take us there, chemical storage is not the best solution. While Fuel cells may provide some relief, I'm not sure they will be optimal long-term.
Electric power is best stored as electric power, and that means that we need to continue to develop ultra-capacitors. While the density is not yet on par with the other two technologies, there is a lot of promising research being done to increase the density. In time it will become competitive with battery densities, but there are much greater advantages to using caps over batteries:
*Caps can be charged very quickly, and as the technology matures, we're becoming more efficient at discharging caps at variable rates while retaining high efficiency.
*Caps can be charged and discharged millions of times with little to no performance loss.
*Caps are very safe for the environment, and also safe to put on board a vehicle and hand-held electronics. No hazardous waste, no explosions, and most likely no chemical leaks, etc....
2) The gap from cars and planes needs to be made back to trains. Japan and Europe have a huge advantage over the US, and we need to invest some money in making smarter decisions. The bullet trains in Japan get groups of people from one place to another at very impressive rates, almost rivaling airfare speeds. When you think about the time it takes to go through security, board a plane, load it with cargo, take-off, get up to cruising speed, land, get off the plane, go through security and get back on the road, there is a lot of overhead.
Bullet trains can offer speeds up to 200 mph, and typically have much faster boarding and unloading times. A trip from San Antonio to Dallas could take an hour and a half, but Google maps tells me that it takes over 4 and a half hours via automobile. I think it would be tough to beat an hour and a half total time from the time you stepped foot in the airport in SA until the time you left DFW. Similarly, you could easily make it from Boston to DC in under 3 hours.
While I understand that planes can make these times currently, they do it on fossil fuels, and they are not efficient. Trains can use a lot less power to move people a lot more efficiently, and they can do it on electric power. Trains with caps on board could pick up charge at various stations, while the passengers load and unload, and then travel on cap power to the next station. Wind and solar power could be set up at these various stations to keep a steady supply of power waiting for the next train to arrive.
Trains also offer safety over both cars and planes. There are much fewer accidents, as there are fewer drivers and more passengers. This is also an advantage in places like Europe where passengers can make their long trips while sleeping in a cabin at night. Imagine boarding a train in Denver at 10 PM and waking up the next morning in New York City with enough time to make an 8 AM meeting. Imagine paying prices similarly to taking a bus to get there.
I know that was a long comment, but I really think this could be promising if the government would tax gasoline more and start funding the construction of a better train transportation system. It would have to start out small, Boston to New York, DC to Philadelphia, Dallas to San Antonio, Atlanta to Miami, Chicago to Detroit. Eventually it could expand. For inner city travel we could use subway systems and buses.
Trains are affordable, efficient, clean, fast, safe, and versatile.
If knowing is half the battle, what is the other half?
There are two kinds of battery life that needs work. One is related to range.. The 8 mile or 250 mile debate. Often overlooked is the battery life in charge discharge cycles. The only reason the Prius doesn't have a dead battery every 1-2 years like a laptop battery or cell phone or business 2 way radio is because they don't deep cycle them in normal use. A Prius seldom has a battery under 50% or over 80% charged.
Heat, deep discharges, cell reversal, and overcharging is hard on batteries. The long range drivers do the worst.. Top the batteries off to get maximum range, run them till they go no more and repeat. Plan on buying new batteries every few years just like you do for your digital camera, MP3 player, cell phone, laptop, and other devices that get deep cycles often.
I think the Toyota 8 mile range is to extend the battery life to 10+ years. It is not for maximum driving range at a high cost.
The truth shall set you free!
It's the assumption of a "reasonable dielectric" that knocked you off your horse. That's where ultracaps have left the building. They're using altogether unreasonable dielectrics, and there is stuff on lab benches that is approaching battery levels right now.
Batteries have energy storage on the order of 1 MJ/kg. The numbers I quoted for the theoretical limits for capacitors are on the order of 1 MJ/kg. You aren't doing a very good job of disproving my point with your examples.
I assumed you had a magical dielectric with a dielectric constant of 1000 capable of supporting electric fields of 10 MV/m (capacitors are typically rated to half the breakdown voltage, so this means 20 MV/m). The best reported dielectrics I've heard of have constants of around 6000, but no breakdown information was provided (10+ MV/m is very hard to get).
Supercapacitors and ultracapacitors get their performance by using nanoporus materials to vastly improve surface area. Electric double-layer capacitors get their performance by using clever techniques to get a very uniform dielectric layer, which lets them work closer to maximum tolerances. No magic in either of these.
If you're claiming much more than 1 MJ/kg, provide citations, or it's vapour.
An acquaintance of mine converted his own vehicle into an electric only vehicle... He drives it to work every day.
For anyone interested, he has a site describing how he did his conversion here:
http://www.evhelp.com/
-Nate
http://en.wikipedia.org/wiki/Tesla_Motors#Sports_s edan
Sports sedan
Tesla is also currently working on an announced but unrevealed sedan, codenamed "WhiteStar", which may be introduced in 2009 as a 2010 model. It is being designed as an alternative to the BMW 5 Series, with an estimated price of $50,000-70,000. [1] WhiteStar is to be built in a new plant in New Mexico.
[edit]Future models
Future plans include a more affordable third model. The development and production of this future model, codenamed "BlueStar", will be funded by profits from the WhiteStar sedan. According to Tesla, if everything goes according to plan, BlueStar will be released in 2012 and cost around $30,000.[3]
-- Boycott Shell
The existing prius has two Motor/Generators, which are in fact needed for the CVT transmission. I think they call it "a 50 KW electric motor" to avoid befuddling people. Also, there are a couple of good reasons not to go with hub motors. In a parallel hybrid, you can get greater efficiency from the ICE drive train if it can drive the wheels directly (thus avoid an electrical conversion step). Secondly, unsprung weight is an issue with a hub motor. In fact, Tesla motors elaborated on this, stating that four wheel drives were the only place hub motors *might* make sense. I have examined some energy flow diagrams from the prius, showing energy conversion losses in all parts of the energy transfer, and it is interesting to say the least. It certainly gives perspective on the series vs parallel hybrid debate. Your proposal that the powertrain should be all electric, and an onboard ICE should be used as generator only is actually proposing a series hybrid. Toyota studied the problem before deciding to go with a parallel setup, knowing that the ICE would be still driving the car most of the time, and the extra conversion loss of putting all the petrol energy through a generator, outweighs the flexibility benefits. (BTW the power steering and A/C compressor in the Prius *are* electric. So is the brake vacuum booster. In fact, I'm not sure there is anything in the car using the mechanical output of the ICE except the motor generators, and the differential).