The important bit in that statement is the + sign - we can raise temperatures ALOT easier than we can lower them...
There are also plans for lowering a planets temperature, and they don't involve building a big honkin' planet-wide AC to send the heat off into space (which would require tons of energy). Removing even a small fraction of the solar power input to a planet is going to cool it off quite a bit. That could be achieved with a bunch of launches, which take much less energy than the AC plan mentioned above.
Then again, most of the solar system is too cold for humans. The only rock in this solar system whose atmosphere is too hot for humans is Venus.
It's still available. You don't have to kill anyone (well, except for some microbes, maybe) for it. (Yes, yes, I know. Killing people and taking their stuff takes much, much less energy than getting anything to Mars. Some people may find the former ethically objectionable, though).
Someone has been reading too much sci-fi -- just try playing around with high school physics for about five minutes on exactly how much work would be required to lower an entire atmosphere one stinking degree, and then compare that to the power consumption of the human race.
Oddly enough, humanity has managed about +0.8K here on Earth in about a century, and that was entirely unintentional.
Some environmentalist has to tell me why we don't just import its natural predator.
Because the overwhelming majority of predators do not rely on a single food source. They will eat what's easiest to catch, which may or may not be what you actually want them to eat.
And don't give me crap about 'well it could be an invasive species too.'
I'm not going to give you any speculative crap, I'll just bet you $10 that the predator will be an invasive species, too.
If it's high up the food chain, it will be forced to live in equilibrium with its prey.
This only works for models where you have one predator and one prey species. Predators which exclusively eat one other species are incredibly rare (figures - reliance on a single food source is a good way to get a species-wide Darwin Award as soon as anything happens to that food source).
Has it ever even been tried?
Yes. The results were usually comparable to trying to put out a burning building by pouring gasoline on it.
The car belongs to a 22 year old male, a 50 year old woman is driving it, obviously stolen. Pull over and handcuff the driver with my gun drawn and ready to shoot if she gives me any lip./cop thinking
Taser. You forget the taser and it's liberal application on the suspect.
See, that's exactly my point. If you wee half as informed on the subject as you pretend, you wouldn't have to ask, because you'd know exactly what I'm referring to. That you don't proves my point, you're ignorant.
I just can't seem to make sense of your junk physics. The HVAC engineer next to me can't either. I'm sorry I'm so completely clueless about junk physics, but I don't have any intention to get any deeper into that particular field than necessary to tell junk physics from the real thing.
Apart from expletives and nebulous claims, you've posted nothing to back up your statements. The textbooks on thermodynamics that I have don't have separate phase diagrams for water being cooled "by a heat pump" and "by an AC", because there's no difference. Neither between "AC" and "heat pump" for most applications (swamp coolers and chunks of dry ice excepted), nor in the way water behaves.
Whether a heat pump can be used for dehumidification only depends on how powerful it is (i.e. how far it can reduce the temperature below the dew point).
Guess what asshat, you've gone from being wrong and ignorant to using fallacies to support you being wrong and ignorant.
More expletives, more nebulous claims. You have no clue about thermodynamics, period, and probably wouldn't recgonize a phase diagram if it came with a big neon sign attached to it. Swear all you want, that won't change the facts. Want to prove me wrong ? Just find that magical phase diagram for "water being cooled by a heat pump".
There can be Only Sun. For all matter is the dust of stars, and there CAN BE ONLY SUN.
Hydrogen isn't the dust of stars. In fact, it could be used as fusion fuel because it is not yet the dust of stars.
If we can actually get energy out of (artificial) nuclear fusion, that would be "the one energy source". Our own little personal sun that we can take with us.
but anyways, AC power is very efficient for very long distances, unlike DC which creates a lot of heat in the line and looses power fast... that's why we have giant AC generating power plants, even when DC has to be inverted to AC to ship the AC anywhere.
That's pretty much nonsense, sorry.
AC is horrible over (really) long distances, because long lines act as inductivities, which increase the impedance (complex resistance) for AC, but not for DC.
AC has a historic advantage over DC because it is trivial to convert AC to a different voltage (using a transformer), whereas it is fairly complicated to do that to DC. Higher voltages decrease the line losses since less current has to flow to deliver the same amount of power. That makes AC better in cases where you just don't have the technology to build an efficient DC voltage converter, or for short- to medium-distance distribution where you don't want to deal with the additional complexity or the efficiency of a transformer beats the efficiency of the DC voltage converter.
If you want to send power over _really_ long distances (1000 km and more), AC is a poor choice. High-voltage DC is used instead.
So my guess of 20 to 30 nuclear plants to entirely run California on nuclear power is much, much closer to reality than "2 or 3", especially if you factor in that there needs to be some extra capacity to cover maintenance times, peak load during the summer, etc.
If everybody in North America was 100% wind powered much of the continent would be without electricity for large periods of time.
That's why you don't go 100% wind powered, but add some solar power to the mix. When the wind is not blowing, it's usually plenty sunny (unless it's nighttime).
Also, the chance that there's no wind _anywhere_ in the country (it's a big place) is pretty slim. Then there's still the possibility of offshore wind parks, and the winds out at sea are more constant and predictable than on land.
If we keep harnessing wind power, won't we run out of wind?
No. Wind is essentially solar power in a different form. We'll run out of wind when we run out of solar power. That's in a couple of billion years. Earth is going to be fried to a crisp earlier than that.
The same thing goes for water power.
Which is also solar power in a different form. We're going to run out of water power when the suns luminosity has increased enough to evaporate all water on the planet. That's about a billion years in the future. We're going to run out of tidal water power when the moon escapes Earths gravity field, which also won't happen for quite a while.
In other words, you can have 50,000 volts or more across your body at a couple microamps of current flow
How ? I = U / R, and R of the human body is in the order of a couple of kOhms. Where do you get the several MOhm resistance you need to get microamps out of 50 kV ?
I don't know what you define as "regular" gasoline, but regular in the UK runs at 93-95 octane, with premium at 98-99. If 93 octane is premium in the US, I pity the poor engines which have to take that crap.
Different countries use different ways to measure octane numbers. Despite that, "regular" in the US is roughly similar to "regular" in Europe, when translated to the same way of measuring. Same goes for premium/super.
What are you trying to say ? That an "real AC" will dehumidify while a "heat pump" will magically leave all the water in the air when it cools it down ? You've just gone from junk engineering to junk physics. It doesn't work that way. You cool air off, and the water will condense, then you feed this air (which at this point is below the temperature you want inside your house/car, and at 100% relative humidity) into the space you want to cool and dehumidify. It heats up again (sunlight/waste heat from people/machines) which will drop the relative humidity.
How much dehumidification you get it a function of the power of the unit. So you may worry about it being underpowered, but it's still a heat pump like in any other AC. Just like the heat pumps in your fridge, freezer, residential AC, car AC, whatever. They're all using heat pumps (unless you've got a swamp cooler at home, which I'd doubt if you live in high humidity conditions).
Oh, and the HVAC person sitting next to me is just ROTFLing.
Fuck off now.
How about you start making sense and get a clue while you're at it ?
I will tell you that in the future, if you don't understand a post you're replying to, and get told so and corrected, it's incredibly pathetic to play stupid semantic games in an effort to gloss over your previous post.
And I tell you that I find it incredibly pathetic when people resort to insults when their attempts to get through with junk science (or junk engineering, in this case) are spotted.
However, there IS a difference. The fact that you don' understand what it is doesn't mean it doesn't exist, just that you're ignorant.
Unless you can tell me, I take that as a proof that you just suck at HVAC engineering and thermodynamics. But that's okay, I hated the thermo and advanced thermo classes too, so don't feel too bad.
It DOES NOT have AC, it has a heat pump. They do not work the same, and in combination with the high ambient temp, will make the car unsuitable for MY needs.
So what's the big difference between an AC and a heat pump (except for the former being an application of the latter) ? Explain please. How do you make an AC without using some sort of heat pump ? Carry lots of dry ice in the trunk of the car ? Evaporative cooling ?
The modern common rail diesel engines are also more efficient than the older "Pumpe-Düse" engines that VW used back when they built the A2 and Lupo.
Not really. High injection pressures are easier to produce with pump-nozzle designs. However, common rail systems are pretty much as good nowadays, and vastly cheaper to produce (iirc the savings of a common-rail injection system are about 100 € per engine, and since the engine is only about 500 €, that's a _huge_ savings).
Another thing: If your common-rail injector fails, you're out of luck and need to have the car towed to the shop. If one of your pump-nozzle injectors fails, you may be able to limp to the shop on the remaining cylinders.
A diesel helps because it uses about the same amount of fuel accelerating as it does when cruising.
Huh ? Mine gets 48 mpg when cruising and <20 mpg when accelerating. I'd be surprised if it were any different since accelerating requires more power than crusing.
Diesel gets its advantages from a) the fuel containing more energy than gasoline, b) the Diesel cycle being inherently more efficient than the Otto cycle and c) having the maximum torque output at lower RPM than a gasoline engine (lower RPM -> less internal power loss to friction).
Acceleration is the only place where a hybrid can make up gas milage, mostly due to regenerative braking.
... and because electric motors have a rpm/torque curve that's _much_ better suited to accelerating than any kind of combustion engine. (Basically, electric motors deliver the
most torque at close to 0 RPM)
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There are also plans for lowering a planets temperature, and they don't involve building a big honkin' planet-wide AC to send the heat off into space (which would require tons of energy). Removing even a small fraction of the solar power input to a planet is going to cool it off quite a bit. That could be achieved with a bunch of launches, which take much less energy than the AC plan mentioned above.
Then again, most of the solar system is too cold for humans. The only rock in this solar system whose atmosphere is too hot for humans is Venus.
It's still available. You don't have to kill anyone (well, except for some microbes, maybe) for it. (Yes, yes, I know. Killing people and taking their stuff takes much, much less energy than getting anything to Mars. Some people may find the former ethically objectionable, though).
Someone has been reading too much sci-fi -- just try playing around with high school physics for about five minutes on exactly how much work would be required to lower an entire atmosphere one stinking degree, and then compare that to the power consumption of the human race.
Oddly enough, humanity has managed about +0.8K here on Earth in about a century, and that was entirely unintentional.
Because the overwhelming majority of predators do not rely on a single food source. They will eat what's easiest to catch, which may or may not be what you actually want them to eat.
And don't give me crap about 'well it could be an invasive species too.'
I'm not going to give you any speculative crap, I'll just bet you $10 that the predator will be an invasive species, too.
If it's high up the food chain, it will be forced to live in equilibrium with its prey.
This only works for models where you have one predator and one prey species. Predators which exclusively eat one other species are incredibly rare (figures - reliance on a single food source is a good way to get a species-wide Darwin Award as soon as anything happens to that food source).
Has it ever even been tried?
Yes. The results were usually comparable to trying to put out a burning building by pouring gasoline on it.
Taser. You forget the taser and it's liberal application on the suspect.
I just can't seem to make sense of your junk physics. The HVAC engineer next to me can't either. I'm sorry I'm so completely clueless about junk physics, but I don't have any intention to get any deeper into that particular field than necessary to tell junk physics from the real thing.
Apart from expletives and nebulous claims, you've posted nothing to back up your statements. The textbooks on thermodynamics that I have don't have separate phase diagrams for water being cooled "by a heat pump" and "by an AC", because there's no difference. Neither between "AC" and "heat pump" for most applications (swamp coolers and chunks of dry ice excepted), nor in the way water behaves.
Whether a heat pump can be used for dehumidification only depends on how powerful it is (i.e. how far it can reduce the temperature below the dew point).
Guess what asshat, you've gone from being wrong and ignorant to using fallacies to support you being wrong and ignorant.
More expletives, more nebulous claims. You have no clue about thermodynamics, period, and probably wouldn't recgonize a phase diagram if it came with a big neon sign attached to it. Swear all you want, that won't change the facts. Want to prove me wrong ? Just find that magical phase diagram for "water being cooled by a heat pump".
Hydrogen isn't the dust of stars. In fact, it could be used as fusion fuel because it is not yet the dust of stars.
If we can actually get energy out of (artificial) nuclear fusion, that would be "the one energy source". Our own little personal sun that we can take with us.
That's pretty much nonsense, sorry.
AC is horrible over (really) long distances, because long lines act as inductivities, which increase the impedance (complex resistance) for AC, but not for DC.
AC has a historic advantage over DC because it is trivial to convert AC to a different voltage (using a transformer), whereas it is fairly complicated to do that to DC. Higher voltages decrease the line losses since less current has to flow to deliver the same amount of power. That makes AC better in cases where you just don't have the technology to build an efficient DC voltage converter, or for short- to medium-distance distribution where you don't want to deal with the additional complexity or the efficiency of a transformer beats the efficiency of the DC voltage converter.
If you want to send power over _really_ long distances (1000 km and more), AC is a poor choice. High-voltage DC is used instead.
So my guess of 20 to 30 nuclear plants to entirely run California on nuclear power is much, much closer to reality than "2 or 3", especially if you factor in that there needs to be some extra capacity to cover maintenance times, peak load during the summer, etc.
That's why you don't go 100% wind powered, but add some solar power to the mix. When the wind is not blowing, it's usually plenty sunny (unless it's nighttime).
Also, the chance that there's no wind _anywhere_ in the country (it's a big place) is pretty slim. Then there's still the possibility of offshore wind parks, and the winds out at sea are more constant and predictable than on land.
No. Wind is essentially solar power in a different form. We'll run out of wind when we run out of solar power. That's in a couple of billion years. Earth is going to be fried to a crisp earlier than that.
The same thing goes for water power.
Which is also solar power in a different form. We're going to run out of water power when the suns luminosity has increased enough to evaporate all water on the planet. That's about a billion years in the future. We're going to run out of tidal water power when the moon escapes Earths gravity field, which also won't happen for quite a while.
Could we kill our atmosphere?
Yes, if we keep dumping enough crap into it.
California is a big place (and has a coastline -> offshore wind parks).
Why would we not have 2 or 3 nuke plants and achieve the same goal with way less environmental impact,
Because you don't need 2 or 3 nuke plants, you need 20 to 30 if you do the math.
Wind power 'feels good' but when you start running the numbers it gets dumb real quick.
So who's going to get one of those 20 nuclear power plants built in their back yard ?
... but soon, they can frag.
"Hold your breath for five minutes."
Physical hurting ensues shortly thereafter.
So if I'm a tourist, then I'm basically screwed ?
Don't forget that this is the US, were anyone must be considered armed until proven otherwise (i.e. until a full cavity search has been performed).
How ? I = U / R, and R of the human body is in the order of a couple of kOhms. Where do you get the several MOhm resistance you need to get microamps out of 50 kV ?
Different countries use different ways to measure octane numbers. Despite that, "regular" in the US is roughly similar to "regular" in Europe, when translated to the same way of measuring. Same goes for premium/super.
Nope. You're doing junk engineering here.
Humidity.
What are you trying to say ? That an "real AC" will dehumidify while a "heat pump" will magically leave all the water in the air when it cools it down ? You've just gone from junk engineering to junk physics. It doesn't work that way. You cool air off, and the water will condense, then you feed this air (which at this point is below the temperature you want inside your house/car, and at 100% relative humidity) into the space you want to cool and dehumidify. It heats up again (sunlight/waste heat from people/machines) which will drop the relative humidity.
How much dehumidification you get it a function of the power of the unit. So you may worry about it being underpowered, but it's still a heat pump like in any other AC. Just like the heat pumps in your fridge, freezer, residential AC, car AC, whatever. They're all using heat pumps (unless you've got a swamp cooler at home, which I'd doubt if you live in high humidity conditions).
Oh, and the HVAC person sitting next to me is just ROTFLing.
Fuck off now.
How about you start making sense and get a clue while you're at it ?
That's because you ... can't. Right.
I will tell you that in the future, if you don't understand a post you're replying to, and get told so and corrected, it's incredibly pathetic to play stupid semantic games in an effort to gloss over your previous post.
And I tell you that I find it incredibly pathetic when people resort to insults when their attempts to get through with junk science (or junk engineering, in this case) are spotted.
However, there IS a difference. The fact that you don' understand what it is doesn't mean it doesn't exist, just that you're ignorant.
Unless you can tell me, I take that as a proof that you just suck at HVAC engineering and thermodynamics. But that's okay, I hated the thermo and advanced thermo classes too, so don't feel too bad.
Hey, the question is even answered here:
http://www.apteraforum.com/showthread.php?t=626&highlight=conditioning
So what's the big difference between an AC and a heat pump (except for the former being an application of the latter) ? Explain please. How do you make an AC without using some sort of heat pump ? Carry lots of dry ice in the trunk of the car ? Evaporative cooling ?
Not really. High injection pressures are easier to produce with pump-nozzle designs. However, common rail systems are pretty much as good nowadays, and vastly cheaper to produce (iirc the savings of a common-rail injection system are about 100 € per engine, and since the engine is only about 500 €, that's a _huge_ savings).
Another thing: If your common-rail injector fails, you're out of luck and need to have the car towed to the shop. If one of your pump-nozzle injectors fails, you may be able to limp to the shop on the remaining cylinders.
The engines in Europe probably require premium gasoline, while the ones in America run with regular.
Huh ? Mine gets 48 mpg when cruising and <20 mpg when accelerating. I'd be surprised if it were any different since accelerating requires more power than crusing.
Diesel gets its advantages from a) the fuel containing more energy than gasoline, b) the Diesel cycle being inherently more efficient than the Otto cycle and c) having the maximum torque output at lower RPM than a gasoline engine (lower RPM -> less internal power loss to friction).
That's a disqualifier.
The fan keeps the car just above ambient temperature when it's parked somewhere. When you're actually driving it, it turns on the actual AC.