That aside, the problem with this is that a turbocharged engine at full output is very inefficient. A larger naturally aspirated engine will always be more efficient than the small turbocharged engine of the same maximum output. That's because a lot of energy is wasted compressing the intake charge, more than can be made up for with the displacement decrease, even with the newest fanciest garrett turbos. The only merit efficiency-wise of turbo engines is engine efficiency at low loads (when the engine is not under boost) relative to the maximum output. There is obviously a balance to be struck here, and that's why 18 wheelers have big v8's with turbo chargers, rather than even bigger engines or smaller engines running under high pressure. Designing a motor vehicle is always a balancing act, and in most cases a turbo is not helpful because of the cost, reliability and other shortcomings versus the benefits.
This isn't really correct. The turbo does increase efficiency because the engine is always dumping a lot of heat into the exhaust that just goes out the tailpipe. The turbo uses this heat energy to compress the intake charge. This isn't wasting energy, but using energy that would otherwise be wasted. Tht is why heavy duty trucks use turbos - that lets the engine use more of the fuel energy for moving the vehicle and less for heating up the air. They also use big inline 6 engines, never V8s, and they use very high pressure - at least twice atmospheric pressure.
That efficiency gain may be fairly small on a gasoline engine, which is more due to how the turbo system is set up than anything (full boost comes at much less than full engine power, for drivability - that means that too much boost would come at full power so the system frequently dumps compressed air to the outside before it reaches the engine, which limits any effiicency gain). A semi engine will have a turbo system designed to come on full at maximum power, which is pretty close to where the engine operates when the truck is going down the road. That lets the entire intake and exhaust system be optimized for where the engine runs most often and that gives efficiency.
Wow. So many comments in this thread. I had to pick this one, just because I actually have one of those "low-powered" S2000's here in the US. The 2.2 liter engine produces the same power and a little more torque than the 2.0 liter that is used in Europe. The difference is that it comes about 1000rpm lower. I don't know about fuel consumption exactly, but I don't think there was any significant change between the 2.0 liter (pre-2004 here) and the 2.2 liter. Redline isn't too different either - 9000 rpm for the 2.0 liter and 8000 rpm for the 2.2 liter. Admittely, it's much cooler to brag about a 9000 rpm redline, but the newer engine is still one of the highest revving car engines on the market and has the second highest specific power (power/displacement) of a production car engine (after the 2.0 liter S2000 engine).
Myself, I'm happy with the 2.2 liter engine as it's a little more pleasant in stop and go driving and still goes like stink when the road is clear. I wouldn't have complained about the 2.0 liter engine either though, if that was what came in the car.
Also, that engine would be horrible in a more practical car. The torque is fine for a car that weighs 2850 lbs, but not for a four door hardtop that comes in at 3500. It would end up feeling less fun to drive than using one of Honda's more conventional engines that have a more balanced power output. To make that practical car faster you need both the power and the torque of that 3 liter V6, or else a turbocharged four-cylinder that can give the same kind of torque (compare the Mitsubishi & Subaru turbo fours with the Honda/Toyota/Nissan 3.5 liter V6 engines - pretty similar numbers).
I got the S2000 for the engine, but I wouldn't have if it was in a car that wasn't suited for it. Developing the entire car is much more than good engine+good car = good package. There are lots of details to get just right.
There have been a number of posts in this debate about the poor level of Apple's service. I'm quite surprised, given the service I've gotten. I have a 14" iBook that is less than a year old. After a few weeks, the DVD burner stopped working and just spit out any disc I put in it. I called Apple and had a shipping box the next day. The computer came back to me 24 hours later wearing a new drive. A couple of months later the computer stopped booting, giving a rather sad sounding beep when I tried to power up. I called Apple, and again I had a box the next day and a computer with a new motherboard in 24 hours.
Both of these issues took one call each, maybe 15 minutes on the line per call. It was a pain to be without the computer for two days total, but I survived. I was somewhat surprised that most of the guts of the computer have had to be replaced within the first year, but it was no problem to have done.
I did buy AppleCare, since I consider a laptop to be a damage-prone device since I carry it around so much. I've had my parents buy the same warranty with their Dell laptops as well. Since both of these problems occured within the first year, I don't think the extended warranty made a difference though.
Perhaps if I had a more non-obvious failure it would be more challenging to get fixed. It's pretty simple when your drive simply won't accept a disc or your computer won't turn on. Still, I would think that at least for hardware problems it would be fairly simple to go through the necessary testing steps to confirm that there is a problem that requires service.
Flame away, those with bad experiences. Or maybe just respond with why it was actually bad...
I can't speak for all plants, but if you look at the latest EPA clean air act regulations for coal plants (where ~60% of electricity comes from), you can determine the emissions per kWe of generated power. It's not too hard to then estimate the emissions required to move an electric car one mile based on all the known factors between the plant and the road (transmission losses, charging losses, drivetrain efficiency, etc.). I did a rough calculation about a year ago, and came up with the electric car producing 5-10x as much emissions as a current ULEV car would on a per mile basis.
It's not necessarily easier to implement and upgrade pollution controls on a few dozen power plants either. The chemistry of burning coal makes it very hard to clean up what comes out of the combustion process, whereas the gasoline engine combustion chemistry is ideally suited for a cheap catalytic converter that can make the exhaust nearly as clean as the air the engine sucked in. Natural gas plants are cleaner, but we don't have all that much gas to use so the price for gas will start going up dramatically if we change the balance of gas/coal power generation too much. The centralized power plants do have a big advantage in CO2 emissions since they are much more thermally efficient. It really depends on what you want to clean up - CO2, smog, particulates, etc.
In the end, it is just really hard to determine what might actually be cleaner - electric cars with their rather dirtier power production in centralized places, nasty chemistry in the batteries (at least for the near future), etc. vs. combustion cars that are set up for efficiency rather than zoom-zoom. Since it is generally more of a political debate than a technical one, I can't really find a good neutral answer to that question.
That's where I started - some cheap MP3 CD player. It was nice, but as many posters have said, it's a royal pain to remember which disc has the song you want, and carrying the discs (and the large player) is annoying. The model I had was also absolutely useless when you tried to find a particular song on the disc - it had some sort of menu, but it was just a long list of every track on the disc, and took forever to find a song.
I now have an iPod mini (thanks Apple for giving them away free to students when buying a laptop so that you could clear stocks in advance of the nano!), and it is light years ahead. The UI is brilliant; I can find any song I want in seconds. It fits in an inner pocket on my jacket or in a pants pocket, so it can always be with me. With iTunes, I can get anything I want from my library on it in a few seconds (and ripping my CDs to non-DRM MP3 files was very quick too). And battery life, while not 30 hours, will last me through 12 hours of driving, with a simple recharge by plugging back into the laptop. They are still somewhat pricey, but I would have bought one if I hadn't gotten the deal with Apple - it is worth the money.
Summary: OK, not so cheap, non-proprietary if you don't use iTunes Store, works with your computer (Linux too, I think?), very good battery life
I have to agree on whether a "desktop replacement" laptop is all that important for most people. For my work I end up using my iBook for nearly everything I do. Yes, it's slow compared to the Dell desktop that I sit next to, but it does everything I need, and it's not all that heavy to carry around. I keep the Dell for when I need to do large amounts of data processing, since the faster processor and larger memory do come in handy then, but otherwise it's just idling and wasting electricity. I would think that, for most people, this could be a better way to work - have a powerful desktop sitting somewhere out of the way, and remote desktop into it from a lightweight laptop. I guess that wouldn't work for games, but I can't think of much else that really needs all that power to be carried with you.
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This isn't really correct. The turbo does increase efficiency because the engine is always dumping a lot of heat into the exhaust that just goes out the tailpipe. The turbo uses this heat energy to compress the intake charge. This isn't wasting energy, but using energy that would otherwise be wasted. Tht is why heavy duty trucks use turbos - that lets the engine use more of the fuel energy for moving the vehicle and less for heating up the air. They also use big inline 6 engines, never V8s, and they use very high pressure - at least twice atmospheric pressure.
That efficiency gain may be fairly small on a gasoline engine, which is more due to how the turbo system is set up than anything (full boost comes at much less than full engine power, for drivability - that means that too much boost would come at full power so the system frequently dumps compressed air to the outside before it reaches the engine, which limits any effiicency gain). A semi engine will have a turbo system designed to come on full at maximum power, which is pretty close to where the engine operates when the truck is going down the road. That lets the entire intake and exhaust system be optimized for where the engine runs most often and that gives efficiency.
Wow. So many comments in this thread. I had to pick this one, just because I actually have one of those "low-powered" S2000's here in the US. The 2.2 liter engine produces the same power and a little more torque than the 2.0 liter that is used in Europe. The difference is that it comes about 1000rpm lower. I don't know about fuel consumption exactly, but I don't think there was any significant change between the 2.0 liter (pre-2004 here) and the 2.2 liter. Redline isn't too different either - 9000 rpm for the 2.0 liter and 8000 rpm for the 2.2 liter. Admittely, it's much cooler to brag about a 9000 rpm redline, but the newer engine is still one of the highest revving car engines on the market and has the second highest specific power (power/displacement) of a production car engine (after the 2.0 liter S2000 engine).
Myself, I'm happy with the 2.2 liter engine as it's a little more pleasant in stop and go driving and still goes like stink when the road is clear. I wouldn't have complained about the 2.0 liter engine either though, if that was what came in the car.
Also, that engine would be horrible in a more practical car. The torque is fine for a car that weighs 2850 lbs, but not for a four door hardtop that comes in at 3500. It would end up feeling less fun to drive than using one of Honda's more conventional engines that have a more balanced power output. To make that practical car faster you need both the power and the torque of that 3 liter V6, or else a turbocharged four-cylinder that can give the same kind of torque (compare the Mitsubishi & Subaru turbo fours with the Honda/Toyota/Nissan 3.5 liter V6 engines - pretty similar numbers).
I got the S2000 for the engine, but I wouldn't have if it was in a car that wasn't suited for it. Developing the entire car is much more than good engine+good car = good package. There are lots of details to get just right.
Both of these issues took one call each, maybe 15 minutes on the line per call. It was a pain to be without the computer for two days total, but I survived. I was somewhat surprised that most of the guts of the computer have had to be replaced within the first year, but it was no problem to have done.
I did buy AppleCare, since I consider a laptop to be a damage-prone device since I carry it around so much. I've had my parents buy the same warranty with their Dell laptops as well. Since both of these problems occured within the first year, I don't think the extended warranty made a difference though.
Perhaps if I had a more non-obvious failure it would be more challenging to get fixed. It's pretty simple when your drive simply won't accept a disc or your computer won't turn on. Still, I would think that at least for hardware problems it would be fairly simple to go through the necessary testing steps to confirm that there is a problem that requires service.
Flame away, those with bad experiences. Or maybe just respond with why it was actually bad...
It's not necessarily easier to implement and upgrade pollution controls on a few dozen power plants either. The chemistry of burning coal makes it very hard to clean up what comes out of the combustion process, whereas the gasoline engine combustion chemistry is ideally suited for a cheap catalytic converter that can make the exhaust nearly as clean as the air the engine sucked in. Natural gas plants are cleaner, but we don't have all that much gas to use so the price for gas will start going up dramatically if we change the balance of gas/coal power generation too much. The centralized power plants do have a big advantage in CO2 emissions since they are much more thermally efficient. It really depends on what you want to clean up - CO2, smog, particulates, etc.
In the end, it is just really hard to determine what might actually be cleaner - electric cars with their rather dirtier power production in centralized places, nasty chemistry in the batteries (at least for the near future), etc. vs. combustion cars that are set up for efficiency rather than zoom-zoom. Since it is generally more of a political debate than a technical one, I can't really find a good neutral answer to that question.
I now have an iPod mini (thanks Apple for giving them away free to students when buying a laptop so that you could clear stocks in advance of the nano!), and it is light years ahead. The UI is brilliant; I can find any song I want in seconds. It fits in an inner pocket on my jacket or in a pants pocket, so it can always be with me. With iTunes, I can get anything I want from my library on it in a few seconds (and ripping my CDs to non-DRM MP3 files was very quick too). And battery life, while not 30 hours, will last me through 12 hours of driving, with a simple recharge by plugging back into the laptop. They are still somewhat pricey, but I would have bought one if I hadn't gotten the deal with Apple - it is worth the money.
Summary: OK, not so cheap, non-proprietary if you don't use iTunes Store, works with your computer (Linux too, I think?), very good battery life
I have to agree on whether a "desktop replacement" laptop is all that important for most people. For my work I end up using my iBook for nearly everything I do. Yes, it's slow compared to the Dell desktop that I sit next to, but it does everything I need, and it's not all that heavy to carry around. I keep the Dell for when I need to do large amounts of data processing, since the faster processor and larger memory do come in handy then, but otherwise it's just idling and wasting electricity. I would think that, for most people, this could be a better way to work - have a powerful desktop sitting somewhere out of the way, and remote desktop into it from a lightweight laptop. I guess that wouldn't work for games, but I can't think of much else that really needs all that power to be carried with you.