We bought solarex polycrystal 85W panels for $550AU, excluding rebate, 8 years ago. But I agree, PV is probably not the cheapest way to cool your house - better insulation, smarter ventilation policy, decent thermal mass in the house and growing pumpkins on the roof would give much the same cooling effect for less than the price of a bottom of the range installed wall unit. Indirect cooling is a better choice too.
Trees are slow to grow, potentially damaging to your house and block sunlight in winter making the house colder. A better solution is to grow fast growing annual creepers such as pumpkin and watermelon each year. I believe Kudzu is popular for this in some areas;).
I've grown pumpkins on my greenhouse roof for this purpose.
Well you could just use an indirect evaporative cooler, which apparently work well everywhere in the states, use minimal water and electricity and push fresh air into the house.
There is lots of technology involved in this race, including carbon fiber bikes, serious aerodynamic studies to improve the bikes, the helmets and even the riders.
I'm sorry Max, but we're going to take your arm off to reduce turbulence...
But that point is wrong. Unless you find a flaw in my previous post (which is quite possible), coal power is at least twice as efficient at producing electricity given a fixed amount of CO2 (by your own numbers). Electric cars are more efficient than petrol cars if you compare electricity energy at the charger to petrol energy at the pump (this is widely demonstrated). Therefore, if we are trying to minimise CO2 emissions electric cars are at least twice as efficient given current coal power technology (which may be significantly worse than the state of the art). Therefore, you can compare 1 electric to 1 petrol, and you find that electric is indeed most CO2 efficient.
You say 'that power will come from new coal plants, that's not really going to help much', but an at least 50% reduction in CO2 given the same driving patterns, current coal power station technology, distribution techonology and battery technology is a huge win. And then we can start using other 'better' energy sources, be they nuclear, wind or kitten.
There was an operating system back in the 80s called 'Walnut' which had everything as persistent objects with various economy things like rent and capabilities. If you (or another process) didn't pay an object's rent, the object would die. It was quite interesting though not really developed to the point that people could use it.
No, the correct conclusion is that if distributed electricity is twice as good for CO2 emisions as standard transport, then an electric car needs to be only half at efficient fuel pump to wheels as an oil burner to get the same overall efficiency. Many people claim that electric vehicles are more efficient fuel pump to wheels (some quoting factors of 3 or more) so the original claim that switching to electric cars would reduce CO2 even for coal burners is actually sounding plausible. Agree?
I think our mistake was to assume that the 35% efficiency was just for the distribution, whereas in fact it is for distribution plus generation. Now any steam generator is going to be both carnot limited and MPP limited and probably can't get much more than than 45% efficient, which means that distribution is more like 80% efficient, which is pretty danged good for something that is mostly solid state. I don't know what the comparable efficiency of fuel transportation is, but I wouldn't mind betting it is worse.
Ok, so the useful energy output of electricity is 11.8, of transportation, 5.3. Both produce the same amount of CO2, which sounds like electricity is twice as good as oil. however, I don't know how much of that 11.8 is due to the 8.1 nuclear (I'd guess that nuclear is say 40% efficient, so it's actually 11.8 - 3 = 9 vs 5.3, which is still nearly twice). So I think you're right that you're wrong:)
That's astonishing! Electricity power generation is only 30% efficient according to that graph, contrary to the 90% efficient claims I've seen elsewhere. If 60% of generated energy is lost in the network, that makes PV look a lot better doesn't it! Thanks for this info.
America as a whole would have to *triple* the power generation and distribution infrastructure to move all cars to electric.
Where did you get this number from?
With more realistic assumptions, an electric car that gets it power from coal causes about 5 times the carbon emission of a gas-powered car.
Let's see, both coal and oil produce most of their energy from CO2 production (oil maybe 20% less due to more hydrogen). Does this mean that electricity production is 5*80% = 4 times less efficient than a diesel engine running locally? So why doesn't everyone run their own diesel generator (and you could cogenerate while you're at it)?
Either you made those numbers up, or there is something you've not mentioned. Economically, your claims do not make sense.
Can you give examples of these subliminal things? I agree 100% about templated layouts being oh so boring:)
Perhaps at some level you are also just producing templated layouts though, it's just that the space of layouts is big enough that you believe they are all different. This might be called 'your style'.
Until I read this post I was unaware what HFCS is, nor that it has been implicated in diabetes. So I fit my scenario quite accurately. You need to learn to think about problems from a distance rather than getting worked up and falsely making the world fit your model, rather than the other way around.
So say you eat berries that I sell. You eat them every day. Then your kidneys die and you spend the rest of your life in misery. Would it be fair for someone to say "If you guzzle these berries - whether through lack of self-restraint or ignorance, that's on you, not on the people that make the stuff.", given that you were ignorant? What if I suspected or knew the berries contained an incidious kidney poison?
This blocks many optimizations. In numerical work, it's a serious problem when the compiler can't tell, say, that "cos(x)" has no side effects. In C, it doesn't; in FORTRAN, it does, which is why some heavy numerical work is still done in FORTRAN. The compiler usually doesn't know that "cos" is a pure function; that is, x == y implies cos(x) = cos(y). This is enough of a performance issue that GCC has some cheats to get around it; look up "mathinline.h". But that doesn't help when you call some one-line function in another compilation unit from inside an inner loop.
C++ has "inline" to help with this problem. The real win with "inline" is not eliminating the call overhead; it's the ability for the optimizers to see what's going on.
C++ also provides const, which I've found has given measurable performance increases (possibly because it can be used for CSE?) as well as making programs more type safe.
You can do memory management without a virtual machine - compiled LISP and the boehm garbage collector are two common examples of this. Indeed, I find C++ with boehm and STL nicer to work with than Java, and faster too.
You have more control over the resulting machine code, so the code can by definition always be faster.
That is not always the case - C doesn't provide a very good fit with modern CPUs. For example, the PowerPC architecture has condition codes which can be operated upon in parallel to arithmetic instructions. However, C's definition of boolean makes these operations never get used, affecting the performance of tight loops considerably.
I suspect that the main reason C is fast is because it has so many dollars spent on making it fast.
I was told that is exactly what happens maybe ten years ago. I'm surprised this is even being published. The evidence for biological origins of gold nuggets is pretty well understood I thought.
Me too. I am totally burned out on technology. Maybe one of these days I will get a cell phone. My buddy taking a picture and sending it to his GF was pretty cool.
The same is true for word processors, I think it more a case of poor word skillz are acceptable. (people setting fonts for sub headings manually, random extra style changes, using spaces for spacing)
You are confusing authors and designers. Most authors just write text and leave layout to their publisher/designer. People who author and design (such as academics) tend to use LaTeX because it does the job faster and cheaper than indesign (particularly for maths).
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We bought solarex polycrystal 85W panels for $550AU, excluding rebate, 8 years ago. But I agree, PV is probably not the cheapest way to cool your house - better insulation, smarter ventilation policy, decent thermal mass in the house and growing pumpkins on the roof would give much the same cooling effect for less than the price of a bottom of the range installed wall unit. Indirect cooling is a better choice too.
Trees are slow to grow, potentially damaging to your house and block sunlight in winter making the house colder. A better solution is to grow fast growing annual creepers such as pumpkin and watermelon each year. I believe Kudzu is popular for this in some areas ;).
I've grown pumpkins on my greenhouse roof for this purpose.
to be honest, all he was really doing was using LPG evaporation to cool the beer. The jet engine was just an excuse for pyrotechnics :)
Well you could just use an indirect evaporative cooler, which apparently work well everywhere in the states, use minimal water and electricity and push fresh air into the house.
Nah. You need your arm to steer with. Only one?
There is lots of technology involved in this race, including carbon fiber bikes, serious aerodynamic studies to improve the bikes, the helmets and even the riders.
I'm sorry Max, but we're going to take your arm off to reduce turbulence...
Ubuntu others are you would like others to Ubuntu you.
Ubuntu others _as_ you would like others to Ubuntu you. ?
But that point is wrong. Unless you find a flaw in my previous post (which is quite possible), coal power is at least twice as efficient at producing electricity given a fixed amount of CO2 (by your own numbers). Electric cars are more efficient than petrol cars if you compare electricity energy at the charger to petrol energy at the pump (this is widely demonstrated). Therefore, if we are trying to minimise CO2 emissions electric cars are at least twice as efficient given current coal power technology (which may be significantly worse than the state of the art). Therefore, you can compare 1 electric to 1 petrol, and you find that electric is indeed most CO2 efficient.
You say 'that power will come from new coal plants, that's not really going to help much', but an at least 50% reduction in CO2 given the same driving patterns, current coal power station technology, distribution techonology and battery technology is a huge win. And then we can start using other 'better' energy sources, be they nuclear, wind or kitten.
There was an operating system back in the 80s called 'Walnut' which had everything as persistent objects with various economy things like rent and capabilities. If you (or another process) didn't pay an object's rent, the object would die. It was quite interesting though not really developed to the point that people could use it.
No, the correct conclusion is that if distributed electricity is twice as good for CO2 emisions as standard transport, then an electric car needs to be only half at efficient fuel pump to wheels as an oil burner to get the same overall efficiency. Many people claim that electric vehicles are more efficient fuel pump to wheels (some quoting factors of 3 or more) so the original claim that switching to electric cars would reduce CO2 even for coal burners is actually sounding plausible. Agree?
I think our mistake was to assume that the 35% efficiency was just for the distribution, whereas in fact it is for distribution plus generation. Now any steam generator is going to be both carnot limited and MPP limited and probably can't get much more than than 45% efficient, which means that distribution is more like 80% efficient, which is pretty danged good for something that is mostly solid state. I don't know what the comparable efficiency of fuel transportation is, but I wouldn't mind betting it is worse.
Ok, so the useful energy output of electricity is 11.8, of transportation, 5.3. Both produce the same amount of CO2, which sounds like electricity is twice as good as oil. however, I don't know how much of that 11.8 is due to the 8.1 nuclear (I'd guess that nuclear is say 40% efficient, so it's actually 11.8 - 3 = 9 vs 5.3, which is still nearly twice). So I think you're right that you're wrong :)
That's astonishing! Electricity power generation is only 30% efficient according to that graph, contrary to the 90% efficient claims I've seen elsewhere. If 60% of generated energy is lost in the network, that makes PV look a lot better doesn't it! Thanks for this info.
America as a whole would have to *triple* the power generation and distribution infrastructure to move all cars to electric.
Where did you get this number from?
With more realistic assumptions, an electric car that gets it power from coal causes about 5 times the carbon emission of a gas-powered car.
Let's see, both coal and oil produce most of their energy from CO2 production (oil maybe 20% less due to more hydrogen).
Does this mean that electricity production is 5*80% = 4 times less efficient than a diesel engine running locally? So why doesn't everyone run their own diesel generator (and you could cogenerate while you're at it)?
Either you made those numbers up, or there is something you've not mentioned. Economically, your claims do not make sense.
Can you give examples of these subliminal things? I agree 100% about templated layouts being oh so boring :)
Perhaps at some level you are also just producing templated layouts though, it's just that the space of layouts is big enough that you believe they are all different. This might be called 'your style'.
Until I read this post I was unaware what HFCS is, nor that it has been implicated in diabetes. So I fit my scenario quite accurately. You need to learn to think about problems from a distance rather than getting worked up and falsely making the world fit your model, rather than the other way around.
So say you eat berries that I sell. You eat them every day. Then your kidneys die and you spend the rest of your life in misery. Would it be fair for someone to say "If you guzzle these berries - whether through lack of self-restraint or ignorance, that's on you, not on the people that make the stuff.", given that you were ignorant? What if I suspected or knew the berries contained an incidious kidney poison?
This blocks many optimizations. In numerical work, it's a serious problem when the compiler can't tell, say, that "cos(x)" has no side effects. In C, it doesn't; in FORTRAN, it does, which is why some heavy numerical work is still done in FORTRAN. The compiler usually doesn't know that "cos" is a pure function; that is, x == y implies cos(x) = cos(y). This is enough of a performance issue that GCC has some cheats to get around it; look up "mathinline.h". But that doesn't help when you call some one-line function in another compilation unit from inside an inner loop.
C++ has "inline" to help with this problem. The real win with "inline" is not eliminating the call overhead; it's the ability for the optimizers to see what's going on.
C++ also provides const, which I've found has given measurable performance increases (possibly because it can be used for CSE?) as well as making programs more type safe.
You can do memory management without a virtual machine - compiled LISP and the boehm garbage collector are two common examples of this. Indeed, I find C++ with boehm and STL nicer to work with than Java, and faster too.
You have more control over the resulting machine code, so the code can by definition always be faster.
That is not always the case - C doesn't provide a very good fit with modern CPUs. For example, the PowerPC architecture has condition codes which can be operated upon in parallel to arithmetic instructions. However, C's definition of boolean makes these operations never get used, affecting the performance of tight loops considerably.
I suspect that the main reason C is fast is because it has so many dollars spent on making it fast.
I was told that is exactly what happens maybe ten years ago. I'm surprised this is even being published. The evidence for biological origins of gold nuggets is pretty well understood I thought.
Not to mention the various russian landers that predated Nasa's efforts.
The solution to this, of course, is to make things that last for less and less time.
Me too. I am totally burned out on technology. Maybe one of these days I will get a cell phone. My buddy taking a picture and sending it to his GF was pretty cool.
Yeah, those Polaroid cameras are pretty spiffy!
The same is true for word processors, I think it more a case of poor word skillz are acceptable. (people setting fonts for sub headings manually, random extra style changes, using spaces for spacing)
You are confusing authors and designers. Most authors just write text and leave layout to their publisher/designer. People who author and design (such as academics) tend to use LaTeX because it does the job faster and cheaper than indesign (particularly for maths).