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When Hybrids Do (And Don't) Make Sense
prostoalex writes "Recently NPR, CNN Money and Wall Street Journal Online have all dedicated some time and space to discussing hybrid vehicle pros and cons. It seems that hybrids do not make much financial sense if (a) you're buying after getting yourself into a debt with not really good interest on a car loan, (b) your battery requires replacement after being out of warranty, (c) your daily commute is not too long, so the price markup you pay for a hybrid does not translate into long-term gas savings." From the CNN article: "They may make a social statement you're interested in, but if you want to save money because of rising gas prices, you're heading down the wrong road, at least for now."
Buy a diesel. And if it's hard or impossible in your region, petition your idiot politicians to loosen up the emissions regulations (diesel emissions, even on older diesels, are generally speaking a lot better than gas emissions, yet diesel's more highly regulated).
Better efficiency (often) than hybrids overall, it's good on highways too, and it's far more cost-effective, too.
Fuck it
I read the WSJ article and the author was comparing buying a new Prius with keeping his old car (can you say Apples to Oranges). When you compare buying a new car (say a 2006 Honda Civic) with a Prius the comparison comes out more favorable for the Prius.
I ran my own numbers and found the Prius to be about $4100 more expensive, but with the $2000 tax credit and driving about 10,000miles/year you would break even in about 7.5 years assuming $3/gallon gas. Of course a bicycle is about $16400 less than the Honda and gas isn't an issue.
The Prius has a nice 8 year/100,000 mile warranty on the power train (batteries included) so you'd be OK with the Prius instead of the Honda. But you'd be rich with the bike.
I'm tired of people repeating things they know nothing about.
http://www.hybridcars.com/faq.html
Hybrids use NiMH batteries, not the environmentally problematic rechargeable nickel cadmium. "Nickel metal hydride batteries are benign. They can be fully recycled," says Ron Cogan, editor of the Green Car Journal. Toyota and Honda say that they will recycle dead batteries and that disposal will pose no toxic hazards. Toyota puts a phone number on each battery, and they pay a $200 "bounty" for each battery to help ensure that it will be properly
recycled.
Not at all. The current generation of hybrids are all running Nickel Metal Hydride "D" batteries, which are pretty safe overall. See Panasonic's disclosure. The worst chemical in them is the Potassium Hydroxide... which you should avoid contact with but which is not generally considered toxic. (Like the lead used in convential starter batteries)
You can simple toss NiMH batteries in the standard municipal waste stream, although recycling them is always a good idea.
The batteries carry an extended warrenty, 7-8 years IIRC. Accelerated testing has shown that they will probably last considerably longer and the price for replacements has already fallen to about $1500.
Buying a hybrid might be hard to justify financially (since the gas savings are unlikely to offset the price premium for a long while) but its still a good thing environmentally.
Unless the heater in the Prius is somehow different from about every other vehicle's on the road, it cannot run on electricity. A car heater is run by blowing air over basically a small radiator (heater core) that the 190F engine coolant cycles through. If the Prius's engine shuts off, the water pump will probably stop and so will the heater.
If you wanted the Prius's heater to keep going when it is on battery power, get an electric water pump. Racing engines and a few others have electric water pumps versus the ordinary ones that are driven off the engine's accessory drive belt or serpentine belt. But this would only work if the engine was warmed up, otherwise you'd just be circulating cold coolant that is not warming up.
If I was both worried about heating up in the winter and also fuel economy, I'd just get a small car like a Focus, a Civic, or a Corolla. The little four-banger will get okay mileage, especially with a stick, it will heat up faster than a Prius, and that $5K you save in the purchase price will buy a LOT of gas.
Just "gittin-r-done," day after day.
Honda's hybrids all get better gas mileage on the highway than in the city:
I've been very happy with the Honda Insight that I bought in 2001.
An interesting trend is that fuel economies tend to be set by the price of the fuel. In other words, car manufacturers only put the effort into improving efficiency when they need to, and that's when people won't take any more. US readers might not believe me on this one, but their fuel is cheap, at least when compared to European prices. And thus, lumbering goliaths (aka SUVs) are still a reasonable proposition. It astounds me when I look at the performance/economy figures for American cars. An example is the new Ford Mustang (a tasty looking car, BTW). The 4L model gets around 200bhp, and about 19/28mpg. My Fiat Coupe is comparible, but gets 260bhp from a 2L engine, and more than 50mpg outside town (I don't live in a city). Hybrids are only there to keep the PR good. Whats needed is a fundamental modernisation of US cars.
Give a man a fire, and he's warm for a day. Set a man on fire, and he's warm for the rest of his life. (Terry Pratchett)
This is not true. I have owned a CIVIC Hybrid for 2 years. Most of the miles I drive are rural, 50MPH roads with very little breaking and I get 48.4 MPG. The car is rated at 51 MPG highway. So, it is a little below the EPA estimate, but not that much. In fact, I bet if I consistently drove the speed limit, I'm sure I could get up to 51 MPG. Not only does breaking charge the batteries, but going down hills charges them too, more than going up hills depletes them.
Also, I have not had ANY problems in cold weather. I live in the Green Mountain, where February is nasty cold. Winter tires do take the MPG down a couple miles though.
When I used to live in Orange County (south of Los Angeles, for those of you that don't know), I rode around on a little 125cc Scooter about 6 months out of the year (summer-time). I spent about a dollar a week on gas. I'm not joking. (Although at today's prices, it would be about 2 or 3 dollars a week). It wasn't fast enough to go on the freeway, but on all the other streets it performed beautifully. It's nice being able to weave through nasty street traffic...and parking is always right outside the store. I reccommend a scooter or small engine motorcycle to everyone during the summer months.
I think, therefore I doh.
I've gone through four Canadian winters with my Honda Insight, and it has fared just fine, even with temperatures below -30 degrees Celsius. The fuel economy is noticeably worse in cold weather, but the same is true of any car.
The Honda Insight in brutally cold weather is still better for fuel economy than almost any non-hybrid in ideal driving weather.
But you have to first get a kit that heats up the oil to at least seventy degrees centigrade before it gets injected into the combustion chamber. I do not understand why car manufacturers do not include this option either as standard or as an optional extra. There's no "new" technology involved here, just a slight engine mod. Cars, buses, tanks, ships, trucks, trains, tractors; in fact virtually any diesel engine can be run on vegetable oil. Diesel is, in fact, a light oil, which is why it usually has been cheaper than petrol - there's less refining involved.
You can simply grow high yield crops to provide the fuel. When the growing season ends in the northern hemisphere, it starts in the southern hemisphere, so you can pay farmers in developing countries in hard cash to grow these crops...
And this is NOT biodiesel I'm talking about. Biodiesel is where you take veggie oil, mix it with methanol, which forms glycerine, which is then washed out with water, and can be used in some diesels, but not all (It tends to rot rubber seals.....) Seems more messy to me, when you can just use straight veggie oil
This alternative source of fuel is already here, and is readily available. i really don't understand why this time, effort, and money is being spent on "alternative" solutions and "new technology" such as hybrids, when a really great starting point is out there already growing in the fields you pass by......doh.
Interested? have a look here.....
http://www.dieselveg.com/
-- Fuck Beta
The water pump in the Prius is already electric. The problem is, the coolant only stays hot for so long before it has to start the engine again to heat it back up. Mine has given me about 5 minutes of heat in cold (0-10 F) weather before it had to start the engine again. (This only applies to stop and go, where the engine has a chance to shut off.) Obviously running the engine a lot in stop and go traffic affects the gas mileage a bit in that car, but the lowest my weekly average has ever been is 45mpg (combined city/highway, my drive to work is about 50% of each). That's still better than the best my old Contour ever got under the best circumstances (37mpg). In summer I normally average 55-58mpg. So yes, cold weather does drop the gas mileage, but even under the worst conditions it's better than most standard cars. The only non-diesel that comes to mind that can achieve 45mpg is the Geo Metro. I normally get around 45-50mpg on the highway.
Diesels are still more efficient even considering the higher density of diesel fuel. About 15 to 20% more efficient based on the mass of fuel consumed.
That is at high power levels, at lower power levels the diesel advantage gets even bigger. Gas engine lose because the air flow is throttled. It takes power to suck the air past a partly closed throttle and that's a loss.
Diesels consume far less fuel at idle than gas engines, partly because of the lack of power loss sucking the air past the throttle plate and partly because of more efficent burning of the fuel.
You comment on mixture (running lean) is also 180 degrees from fact. Gas engine run close to 15:1 air fuel ratio. About 12.5:1 to 17:1 for extremes. The richest diesels ever gets is about 20:1. At idle a diesel is more like 100:1.
#2 Diesel fuel is about 15% denser than gasoline. Diesel cars typically have about 30% lower fuel consumption than equivilant gasoline powered cars.
NASA created a catalytic converter system using frikkin' lasers that works at cooler temperatures.
"A witty saying proves nothing." ~Voltaire
"d'Oh!" ~Homer
Any modern (second half of the '90s onward) VW turbo diesel will give you mileage on a par with the hybrids, and you can run biodiesel or petrodiesel, or a mix. One of the new Beetles or a Golf can get upwards of 50MPG. The Jettas are not a lot worse, and neither are the Passats.
;-)
I know 2 people with Honda hybrids - a Civic and the little 2-door one (Insight?). The Civic gets in the low 40s MPG-wise, and the other one is around 50. Another person I know with a Jetta TDI gets mileage comparable to the Civic Hybrid, on biodiesel.
And unlike petro-anything, biodiesel will only come down in price as distributed production (not "energy industry" controlled production) increases. Then there's the comfort factor of a technology that's been around the block, as opposed to a rather kludgy hack that puts a bunch of battery acid travelling 65+ MPH two and a half feet from the back of your head while you're strapped into a nifty compactable container.
BTW - if you're in the Southeast US and looking to sell a reasonably-late-model Jetta or Golf TDI, I'm in the market.
Eloi are stupid, throw morlocks at them!
I've owned a Prius for over a year now, and I can say that even under the worst circumstances it gets better gas mileage than my last car did under the best circumstances. Gas mileage is a bit lower on the highway than in the city (electric only is only good up to 34mph), but it's not *that* bad. I consistently get 45-50mpg on the highway, and I consistently get 50-55mpg average city/highway. The lowest my weekly average has ever gotten, during the dead of winter, with the heater blasting (which makes it run the engine more - the water pump is electric but the engine has to start whenever the coolant drops below a certain temp), is 45mpg. The only way I can see to get the mileage lower than that would be to drive it like a race car. I guess if you floor it constantly and use the brakes a lot rather than let the regenerative brakes work, you could drop it below 40mpg, but I don't think I could do it without trying.
What I can't figure out is: why not make a straight diesel-electric hybrid? No transmission, just diesel-->generator-->motors + batteries. The diesel wouldn't have to be nearly as powerful as, say, a TDI, because the batteries could handle short peak loads, then recharge during cruising/coasting/braking. The diesel could run continuosly at it's peak efficiency, as long as power was demanded. The cars would cost far less to produce, without the need for a transmission. It seems to me that such a car would be cheaper, faster, more fuel efficient, and more reliable.
If you don't know where you are going, you will wind up somewhere else.
>> And remember that Diesels idle very inefficiently
That's the exact opposite of correct!
I have a VW Diesel Golf.
It holds four adults such that a one hour drive is not uncomfortable but I wouldn't go cross-country.
I get 600 miles to a 13 gallon tank of gas.
It holds all my scuba gear without dropping the seats.
Now if I could get Bio-Diesel it would be damn near perfect! No sulfur, very clean, biodegradable fuel and the Oil Cronies don't get a friggin' dime.
while motorcycles ARE inherently more dangerous and more difficult to operate than cars (ie. they offer little or no protection in a crash, must be balanced, etc.) the common perception that they are "dramatically more dangerous than cars" is just plain misinformation.
m ot/motorcycle/00-NHT-212-motorcycle/toc.html
feel free to check out the comprehensive study published by the national highway traffic safety administration here:http://www.nhtsa.dot.gov/people/injury/pedbi
the basics: learn how to ride properly, wear a good helmet (full face, DOT and SNELL approved), obey the speed and traffic laws, don't drink and drive, remain aware of your surroundings and the other drivers around you. follow these basic rules and you probably won't get into a serious accident. if you're pulling wheelies on the highway at 95 mph while drunk and not wearing a helmet on the first day you get your license, you've got the life expectency of a jellyfish in a blast furnace (to steal a phrase from terry pratchett).
for a great deal of riders "going down" involves a twisted ankle and scraping up one of your farings after slipping on a patch of gravel at an intersection, not blasting into a guard rail at 80 mph.
-dk
Dream with the feathers of angels stuffed beneath your head.
1. Actually, only the Prius gets worse highway mileage than city. The Honda hybrids all get better highway than city. I don't actually know about the newer hybrid SUVs and whatnot.
2. However: The Prius still gets better highway mileage than any other internal-combustion gas car out there (there are diesels and cars you can buy in other countries that get better, though)
3. To clear up some misconceptions I've noticed, the reason the Prius gets better mileage with stop-and-go driving is that there's a lot less wind resistance at the low speeds. This is true for normal cars, too, but they have the problem that all of their braking energy is lost, they keep running their engines when they're not going anywhere, and most of them have certain speeds where they're more efficient than others because of their gearing. The Prius saves some of its kinetic braking energy, turns off its engine when it stops moving, and has a CVT.
The Prius is more efficient than normal cars on the highway for a couple of reasons: It's seriously streamlined, so it has less wind resistance than just about anything out there, and the CVT means it's always running at peak efficiency.
(I've owned my Prius for the past four months or so. I realize it's not going to save me any money whatsoever over, say, a non-hybrid Honda Civic, but it's just such a cool car that I'd still buy a Prius if I had to do it all over again. Oh, and I normally get around 50-53mpg with my 10% city, 90% interstate commute. The thing that really kills me is the bridges I have to go over. Driving uphill makes my gas mileage sad.)
(But I still get better gas mileage going uphill than the best-case gas mileage of my old GMC Safari van)
"Unless the heater in the Prius is somehow different from about every other vehicle's on the road, it cannot run on electricity. A car heater is run by blowing air over basically a small radiator (heater core) that the 190F engine coolant cycles through. If the Prius's engine shuts off, the water pump will probably stop and so will the heater. "
Err ... no.. The Prius's Heater is quite different.. (IMHO ... Far
Superior). .
Machine Design 2004 Toyota Prius
"After 1,500 miles of driving in some of the coldest January temperatures on record, I'd summarize the 2004 Toyota Prius as a quiet, roomy car that happens to have a hybrid drivetrain and an excellent heater. Quick heat is no fluke. The Prius stores some coolant in an insulated reservoir when it shuts down. Later, when restarted, the stillhot coolant circulates into the engine primarily to reduce emissions, but an additional benefit is near-instant heat. This is one of several unusual features on this car.";
I saw the research papers from a project just like this that was done some 10+ years ago by a really huge automotive company in America. The problem is people.
The design was Engine to Generator to Batteries to Electric Motor. In a sense the batteries were not much more than really huge capacitors across the leads to balance out high demand use.
It also used regenerative braking to regain power.
If you drove like a typical driver who would jack rabbit the starts and slam the brakes then the massive amount of current you are pushing into and out of the batteries will create so much heat. The tests were abandoned shortly after they managed to explode a number of the batteries by doing this.
That's why they don't do this.
If there was a current limited control on the entire engine system then it would work very well. But you would have to risk selling vehicles that don't do 0-60 in
Until the society as a whole is willing to put up with less zoom-zoom performance and more economical and environmental considerations these concepts have no chance..
That's crap, as are the above comments that chime in about actual savings, true mileage etc, without considering what americans pay for cars, how much gas we consume, etc.
Here are some actual facts:
The average price PAID for a car in the US is about 26 grand. The best selling cars in the US are the Ford F-150, and the Chevy Silverado--gas guzzlers, with MSRPs that start at about 10 grand more.
My parents have a 2003 model prius, which they paid 21 grand for (and the MSRP is still about that). Granted, you can't haul wood in the thing, but it fits 4 adults quite comfortably, has no trouble doing 85 on the highway if need be, and while not a performance hound, it's a fun little drive.
As far as mileage, they put about 12-15,000 miles on it every year, and regularly drive it in both suburbia and on regular 2-3 hour hauls; they also take a couple 7-8 drives hour per year. My father, bless him, has kept a journal of the car's mileage the entire time (along with his other cars), and depending on who is driving--a huge factor, mind you--he has an overall average mileage of 43.7 MPG. (When my leadfoot mother drives, it drops as low as 32 MPG, usually 35 or so, and my dad regularly gets 50-plus MPG, but mostly because he's a passive driver.) That's a sampling of over 2.5 years of driving (and the 2004 model apparently gets better mileage, is bigger, and has a more powerful engine).
Now, compared with his buick century, which remarkably gets 22 MPG on a good day, and that's substantial. He admitted the first year he bought the Prius that he was only realizing $600 gas savings per year, but now that gas has more than doubled in price since then (and not going to get better any time soon), he's sitting pretty. The government kicked in a nice retroactive tax break for him as well.
So for those who say it's too expensive--you already pay more. For those who say the mileage sucks--you likely get half as much. And it's still virtually emission-free.
Righteous indeed.
One point people miss is that the designers of the Prius, at least, were pursuing low emissions with fuel economy being a nice side effect.
When the exhaust system is cold, there's a tradeoff between fuel economy and emission control. The car's software chooses emission control. Drive a Prius for 15 minutes and look at the central display's bar graph of fuel economy over time. It looks like a staicase, where each 5-minute average is much higher than the one before. Until you get the catalytic converter fully warmed up(*) you won't see the advertised mileage. In a five or ten minute commute you can even get a Prius to average less than 40 mpg.
(*) The car's software is so determined to keep the catalytic converter at its most effective temperature that it will start the gas engine even if the car is stopped and the battery is charged, just to keep the catalytic converter warm.
If all your trips are under 10-15 minutes then buy a Prius for the reliability, comfort, or low pollution -- you won't get the gas mileage.
They are the people you see constantly speeding up and down, speeding on the freeway at 80mph+, are hard on the accelerator and hard on the brakes and zipping from stoplight to stoplight.
I've yet to find a car which doesn't meet it's EPA mileage estimates when driven even only somewhat smoothly.
Tips to improve your Gas Mileage really should be tought in basic drivers ed as they would make driving a lot less stressful as well as being more fuel efficient.
Good point about regenerative braking. But wait, there's more.
Gas engines have one speed and power setting where they're most efficient. This setting is almost certainly not identical to your freeway cruising speed. A hybrid can cycle the gas engine between most-efficient and turned-off using the battery to keep your speed constant.
Good point about driving technique too. Another way to put it is that every time you hit the brakes in a 20th-century car you have just pumped oil from a war zone and burned it to heat your brake linings.
Turbines have several advantages over piston engines: ...)
- less noise (almost none)
- much better efficiency (double IIRC)
- can burn anything (vegetable oil, natural gas, jet fuel
- less pollution (they burn better IIRC)
They also have issues that make it impractical for regular cars:
- must turn very fast to achieve the best efficiency
- short range of usable speeds
- high temperature (requires expensive materials)
Those issues (except the last one) are automagically solved when the turbine is connected to an alternator instead of a car transmission.
So why not just build a turbine-electric hybrid? The efficiency would be way above any existing car.
From a hazard standpoint, see the EPA's page on nickel. As metals go, it's not amazingly toxic, but it's not benign, either -- note that the RfD is 0.02mg/kg.
The Panasonic page was interesting; I'm not sure how they got the batteries classified as "safe for disposal in the normal municipal waste stream", but it probably wasn't on the merits.
Human being (n.): A genetically human, genetically distinct, functioning organism.
I can't speak for mine vehicles, but for locomotives this is balderdash. Only a small number of locomotives are hybrids, you can google for "green goat" to read about those. I've run one, it's weird compared to a diesel-electric, but quiet. Doesn't have much oomph, needed a conventional diesel electic to help pull.
Most "modern" locomotives (the ones that are still in daily use date from the 50's on up) are diesel electric. When they use the electric traction motors for braking, the resulting electricity is burned off in a grid, and this is called dynamic braking, as opposed to using the brake shoes around the wheels for braking.
Tha batteries used in most locomotives serve the same purpose as a battery in a conventional car or truck (starting, powering accessories and lights, etc.)
If you spent 3 years researching hybrids, why can't you spell them?
Hybrid gasoline engines are designed differently because low-end torque is not needed because of the electric assist. They use a "5-stroke" engine instead of your standard 4-stroke...however for propeller heads, its more like a virtual 5th stroke. They certainly play games to make the engine more efficient at the cost of less low-end torque. You likely can't pull the same trick with a diesel which is known for low-end torque (think dump trucks).
It has nothing to do with how hot the brakes get, except that the heat is the direct result of the wasted energy.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
The IEEE Spectrum magasine also ran a story recently on hybrids.
They focused on so-called plug-in hybrids, the modified stock hybrids such as the Prius with larger batteries, allowing them to be run on electrical power alone for, say urban conditions. Here's a link.
--cros13