You're correct. Best would be to turn them off when not in use. One does go off at night. The other gets put on the dimmest setting at night as it's used as a night-light - the only fixture on at night to allow safe passage. The rest of the fixtures go on and off as needed.
CFLs definitely vary in life with use. I've seen charts showing as little as a few thousand hours if they're turned on for only 5 minutes at a time and up to 20k hours when left on. Starting surges play a profound role in the life of fluorescents.
The quality of the bulb is the key factor. If you buy crap bulbs, they won't last, and unfortunately there are too many manufacturers piling in to make a quick buck and it is giving the field a black-eye. I've installed a half dozen Cree LR6 "bulbs" for recessed lights. One has been running two years, the others about a year. No failures. Excellent quality light. While this is about LEDs, I'll comment on CFLs as well because there are a lot of people with similar poor lifespans with those. Again, crap bulbs = short life. I've got a dozen outdoor lights that get used in all temperatures. One failed, the rest have worked without flaw for three years. Indoors, I've got two living room, 3-way fluorescent bulbs that burn 24/7/365 (yes, this wastes energy but I can't convince the wife to turn them off). Three years and 26,000 hours later and not a failure. I have a bulb above my shower in a recessed light fixture, considered a "worst case" for CFLs - never had to replace since installation 4 years ago.
The fundamental technology is excellent. Many manufacturers suck.
That's excellent. From a thermodynamics and energy efficiency perspective, we're going to see much more use of waste heat and natural cooling. Right now, buildings systems are not integrated. You have lights, generators, computers, and scads of other heat producing equipment that needs to be cooled by tons of air conditioning capacity. Due to the large cost savings in commercial settings, you can afford to build custom dampering systems as described - bring room air that you want cooled through the datacenter, flush it out, then use this air to heat the space as needed. Once the rooms are up to temperature, introduce fresh air to the data center machines and flush the warmed air back outside (I foresee global warming snark...)
Another option is to use water cooling with a geothermal cooling system. You don't need the heat pump portion, just circulate the water to bleed off the heat then run that into the ground as a big heat sink. Waste heat can first be transferred as needed for operational needs, taking further advantage of the energy.
Finally, another option is to utilize the new heat to electricity systems. They're terribly inefficient in applications at these temperatures, but they could provide a first stage of energy recapture.
As for those worried about humidity - relative humidity relates to temperature. If you take 80% humidity air at 75F and blow it over a hot CPU, the relative humidity will be low. There's no concern about condensation unless the CPUS are running colder than ambient.
(Sorry that this is getting astray of the original posting.)
"Any nontrivial image-processing consists of mathematics beyond high school algebra"
Heh. That's what much of our competition thought, so they implemented many of their routines in the Fourier domain. We did real-world image processing and analysis in the spatial domain. Pixel addition, subtraction, multiplication and division. Real-time image processing. We survived while the competition failed. They failed because they created programs that were correctly implemented but didn't satisfy the customers' needs. We addressed those needs in an extremely pragmatic manner and crushed the competition.
We implemented all our own code. Complex, non-trivial code - but still required no higher level math or proofs. This was for an application that might be considered a scientific version of Photoshop.
How about most other real-world software? Implementing word processors or even spreadsheets largely requires only very basic math.
I do agree that "Programming is a trade skill. Computer Science is an academic discipline." Why can't Johnny code? Because many companies won't even look at a candidate unless they graduated with high marks in a CS degree and traditional CS programs are largely irrelevant. That's cool with me because that leaves many of the truly talented programmers available to hire:-)
There's a huge difference between Computer Science and computer programming and being skilled at one does not imply any level of competence at the other.
I attended one of the top engineering colleges in the early 80's and studied computer science and engineering. Prior to that, I grew up writing code and had a passion for problem solving. I went to college expecting the other CS majors to have similar competencies. What I learned was that the standard CS curriculum at the time didn't train great programmers, it trained computer scientists.
While there were several programming courses we all took, there was considerable emphasis on math, analysis and proofs. The students were taught about Turing machines, algorithmic efficiency and the like. While I enjoyed the graphics, data structures and OS design courses, I was shocked at how little training there was about actual programming, style and issues pertinent to actual large scale program development. I graduated highly disaffected by the conventional CS curricula.
So what did I do? Well, while a student, I started a company and hired the best programmers I could find amongst my classmates. As it turned out, none of these were good CS students but they were fabulous programmers. And they weren't the type that just churned code. They were adept at writing quality code and continue to be to this day. We understood the fundamentals and applied them. We cared about programming and what we did. But none of us was what one would consider a brilliant computer scientist. We barely passed our higher level math classes and theoretical computer science courses. And you know what? In 20 years of professional programming, very successfully I would add, we never needed those skills. The level of math we used in developing our applications rarely progressed above high school algebra and geometry. A little pre-calc and first year calculus maybe, but that's it.
Lest you think we were DB programmers or just did GUI programming, far from it. We developed a large image processing and analysis system for biomedical imaging.
Would I say there's no need for computer scientists? Not at all. Their work provides the foundation for many advances in programming. However many of them have no place in front of a keyboard except for writing papers about programming. Likewise, many talented programmers couldn't solve a proof to save their life. They are two distinct disciplines with some overlap.
The problem is that most programmers can't even program single-threaded in C without bringing the machine crashing down. As the OP's comment showed, thinking about multi-threaded coding issues makes their head explode.
It's like the manual transmission - those that want the best performance learn how to use it but most people just want to cruise.
Ultimately, it won't matter whether the masses are programming single or multi-threaded, because their apps are inefficiently designed. What will matter is how a few select pieces of code run. This includes the OS, some games and a few apps like PhotoShop. Those coders on those will have to continue to use multi-threaded techniques to get decent performance/system responsiveness. The multi-core processors will win out. AMD is wasing their time.
um, if you're going to make such accusations then you better back them up. Wasn't there a roomful of people there who saw your presentations? If Paul & co. ripped you off, find some of those people and have them back you up. It should be trivial to prove your case and drive the StartUp school out of business. OTOH, if you can't substantiate your claims, then you're walking on thin ice.
exactly!
I did in fact start a company while in college (while a classmate of PG, BTW) and had the good fortune of having 'adults' provide guidance and some cash. Through the years, all the hard work would have been for nothing if not for the advice of those who had 'been there, done that'.
Even in my 30's, my most valuable resource was the advice of other entrepreneurs - no amount of cash could have replaced that.
I totally agree with the idea that older, more entrenched people are unlikely to take the necessary risks to bootstrap a start-up. Sure, there are some old entrepreneurs, but most of them depend upon real startup money so they can feed their families, pay mortgages etc. As such, they are far less likely to attempt anything too revolutionary because those ideas wouldn't be funded. I sure as h*ll wouldn't give up my current lifestyle to go back to coding 16 hours a day.
I agree that it's a great thing if it works as advertised. From the sounds of it, it beats just about all the alternatives. So don't get me wrong, I'm all for this technology and feel that the governments of the world should fund this aggressively to get it developed.
The main argument I have is with the sentiment expressed that it alone can solve the world's energy problems.
It's the scalability that makes all of this a losing proposition. The amount of energy that each of us uses every day is significant when you start looking at the amount of biomass necessary to sustain that usage.
Let's do a calculation. If you get 75% of the
waste converted to diesel (same as #2 fuel oil), then it takes 9.46 pounds of waste for each gallon of fuel. If a typical person uses 20 gallons a week, then you've got roughly 190 lbs waste needed just to produce this energy.
Add to that the fuel required to heat your home. That's another 1000 gallons/year, so now we're up another 182 lbs/week. If you're generous, let's say that the fuel efficiency doubles and homes go to solar heating for 75% of their needs. Now you're at 190/2 + 182/4 = 140lbs/week => 15 gallons/oil per person for driving and heating.
Multiply this by 294 million people in the us, divide by 4 to be generous and say that each family will use this amount of fuel and you
get a little over 1 Billion gallons of oil per week.
If you perfectly recycled everything you ate and threw away, you'd still fall far short of energy parity.
And those fields? Of corn/hemp/soybeans/turkeys? You're still looking at needing many pounds per week per person. How many pounds of net energy matter can an acre produce per year?
Any way you slice it, we're living on borrowed energy. Those billion barrels of oil per week supply lots of energy compared with fields of turkeys and other biomass.
The only sustainable long term solutions are:
1 - greatly reduce our consumption of non-renewable energy sources
2 - recycle 100% of all waste matter
3 - use 100% renewable sources for almost all power sources (home power, ground transportation)
well, I Googled and found one reference that says:
In California over 500,000 acres of rice are grown each year. Each acre produces 1-2.5 tons of rice straw which have been until now burned. Alternative methods of disposal are needed, and conversion to ethanol has been under development for several years. There are currently two projects underway proposing to use rice straw: one in California (Gridley) and one in Jennings, LA. If the Gridley project is fully implemented, it will add 25 million gallons of production to California's already-thin 9 million gallons per year. Barriers include collection costs and the high silica content (13%) of rice straw.
Other agricultural wastes include orchard trimmings, walnut and almond shells, and food processing wastes, for a total of about 700 MGY potential if ALL agricultural wastes were used. This is, of course, impractical, as some must be returned to the soil somehow, plus collection and transport costs will have an effect on viability of a particular waste product. Agricultural waste has the potential to satisfy a significant share of demand, with many factors to be considered when proposing a bio-refinery based on any feedstock, which are determined by full life-cycle analysis.
If 25% of the available material were used, about 175 million gallons per year could be produced.
That's good for less than one day of the country's oil consumption.
I still think that the technology is a great thing, since it puts all these waste products to good use, but I don't believe that, it is going to allow the U.S. to free itself from foreign oil any time in the near future.
Could you give a reference to support your statement that "californias agricultural waste which is mostly funneled down into a southern californian dessert lake area could supply enough fuel to satiate the US oil supply."
I find that extremely difficult to believe. Based on US governemnt stats, we used 262 million gallons of oil PER DAY in 1998. That's a couple billion pounds/day. Even if the process is 80% efficient, you're talking about about 2.5 billion pounds of oil rich waste processed per day to supply the country's oil needs. That's 10 pounds for every person in the U.S. per day.
If I've done my calculations correctly, than that amounts to about 1.25 million cubic meters of sludge every day. or roughly 1 square kilometer, one meter deep.
If your stats are correct, they're simply astounding (and really gross!)
Slashdot Mirror
You're correct. Best would be to turn them off when not in use. One does go off at night. The other gets put on the dimmest setting at night as it's used as a night-light - the only fixture on at night to allow safe passage.
The rest of the fixtures go on and off as needed.
CFLs definitely vary in life with use. I've seen charts showing as little as a few thousand hours if they're turned on for only 5 minutes at a time and up to 20k hours when left on. Starting surges play a profound role in the life of fluorescents.
The quality of the bulb is the key factor. If you buy crap bulbs, they won't last, and unfortunately there are too many manufacturers piling in to make a quick buck and it is giving the field a black-eye.
I've installed a half dozen Cree LR6 "bulbs" for recessed lights. One has been running two years, the others about a year. No failures. Excellent quality light.
While this is about LEDs, I'll comment on CFLs as well because there are a lot of people with similar poor lifespans with those. Again, crap bulbs = short life. I've got a dozen outdoor lights that get used in all temperatures. One failed, the rest have worked without flaw for three years.
Indoors, I've got two living room, 3-way fluorescent bulbs that burn 24/7/365 (yes, this wastes energy but I can't convince the wife to turn them off). Three years and 26,000 hours later and not a failure. I have a bulb above my shower in a recessed light fixture, considered a "worst case" for CFLs - never had to replace since installation 4 years ago.
The fundamental technology is excellent. Many manufacturers suck.
That's excellent.
From a thermodynamics and energy efficiency perspective, we're going to see much more use of waste heat and natural cooling. Right now, buildings systems are not integrated. You have lights, generators, computers, and scads of other heat producing equipment that needs to be cooled by tons of air conditioning capacity. Due to the large cost savings in commercial settings, you can afford to build custom dampering systems as described - bring room air that you want cooled through the datacenter, flush it out, then use this air to heat the space as needed. Once the rooms are up to temperature, introduce fresh air to the data center machines and flush the warmed air back outside (I foresee global warming snark...)
Another option is to use water cooling with a geothermal cooling system. You don't need the heat pump portion, just circulate the water to bleed off the heat then run that into the ground as a big heat sink. Waste heat can first be transferred as needed for operational needs, taking further advantage of the energy.
Finally, another option is to utilize the new heat to electricity systems. They're terribly inefficient in applications at these temperatures, but they could provide a first stage of energy recapture.
As for those worried about humidity - relative humidity relates to temperature. If you take 80% humidity air at 75F and blow it over a hot CPU, the relative humidity will be low. There's no concern about condensation unless the CPUS are running colder than ambient.
(Sorry that this is getting astray of the original posting.)
:-)
"Any nontrivial image-processing consists of mathematics beyond high school algebra"
Heh. That's what much of our competition thought, so they implemented many of their routines in the Fourier domain. We did real-world image processing and analysis in the spatial domain. Pixel addition, subtraction, multiplication and division. Real-time image processing. We survived while the competition failed. They failed because they created programs that were correctly implemented but didn't satisfy the customers' needs. We addressed those needs in an extremely pragmatic manner and crushed the competition.
We implemented all our own code. Complex, non-trivial code - but still required no higher level math or proofs. This was for an application that might be considered a scientific version of Photoshop.
How about most other real-world software? Implementing word processors or even spreadsheets largely requires only very basic math.
I do agree that "Programming is a trade skill. Computer Science is an academic discipline." Why can't Johnny code? Because many companies won't even look at a candidate unless they graduated with high marks in a CS degree and traditional CS programs are largely irrelevant. That's cool with me because that leaves many of the truly talented programmers available to hire
There's a huge difference between Computer Science and computer programming and being skilled at one does not imply any level of competence at the other. I attended one of the top engineering colleges in the early 80's and studied computer science and engineering. Prior to that, I grew up writing code and had a passion for problem solving. I went to college expecting the other CS majors to have similar competencies. What I learned was that the standard CS curriculum at the time didn't train great programmers, it trained computer scientists. While there were several programming courses we all took, there was considerable emphasis on math, analysis and proofs. The students were taught about Turing machines, algorithmic efficiency and the like. While I enjoyed the graphics, data structures and OS design courses, I was shocked at how little training there was about actual programming, style and issues pertinent to actual large scale program development. I graduated highly disaffected by the conventional CS curricula. So what did I do? Well, while a student, I started a company and hired the best programmers I could find amongst my classmates. As it turned out, none of these were good CS students but they were fabulous programmers. And they weren't the type that just churned code. They were adept at writing quality code and continue to be to this day. We understood the fundamentals and applied them. We cared about programming and what we did. But none of us was what one would consider a brilliant computer scientist. We barely passed our higher level math classes and theoretical computer science courses. And you know what? In 20 years of professional programming, very successfully I would add, we never needed those skills. The level of math we used in developing our applications rarely progressed above high school algebra and geometry. A little pre-calc and first year calculus maybe, but that's it. Lest you think we were DB programmers or just did GUI programming, far from it. We developed a large image processing and analysis system for biomedical imaging. Would I say there's no need for computer scientists? Not at all. Their work provides the foundation for many advances in programming. However many of them have no place in front of a keyboard except for writing papers about programming. Likewise, many talented programmers couldn't solve a proof to save their life. They are two distinct disciplines with some overlap.
The problem is that most programmers can't even program single-threaded in C without bringing the machine crashing down. As the OP's comment showed, thinking about multi-threaded coding issues makes their head explode.
It's like the manual transmission - those that want the best performance learn how to use it but most people just want to cruise.
Ultimately, it won't matter whether the masses are programming single or multi-threaded, because their apps are inefficiently designed. What will matter is how a few select pieces of code run. This includes the OS, some games and a few apps like PhotoShop. Those coders on those will have to continue to use multi-threaded techniques to get decent performance/system responsiveness. The multi-core processors will win out. AMD is wasing their time.
um, if you're going to make such accusations then you better back them up. Wasn't there a roomful of people there who saw your presentations? If Paul & co. ripped you off, find some of those people and have them back you up. It should be trivial to prove your case and drive the StartUp school out of business. OTOH, if you can't substantiate your claims, then you're walking on thin ice.
exactly! I did in fact start a company while in college (while a classmate of PG, BTW) and had the good fortune of having 'adults' provide guidance and some cash. Through the years, all the hard work would have been for nothing if not for the advice of those who had 'been there, done that'. Even in my 30's, my most valuable resource was the advice of other entrepreneurs - no amount of cash could have replaced that. I totally agree with the idea that older, more entrenched people are unlikely to take the necessary risks to bootstrap a start-up. Sure, there are some old entrepreneurs, but most of them depend upon real startup money so they can feed their families, pay mortgages etc. As such, they are far less likely to attempt anything too revolutionary because those ideas wouldn't be funded. I sure as h*ll wouldn't give up my current lifestyle to go back to coding 16 hours a day.
I agree that it's a great thing if it works as advertised. From the sounds of it, it beats just about all the alternatives. So don't get me wrong, I'm all for this technology and feel that the governments of the world should fund this aggressively to get it developed.
The main argument I have is with the sentiment expressed that it alone can solve the world's energy problems.
arggh!
It's the scalability that makes all of this a losing proposition. The amount of energy that each of us uses every day is significant when you start looking at the amount of biomass necessary to sustain that usage.
Let's do a calculation. If you get 75% of the waste converted to diesel (same as #2 fuel oil), then it takes 9.46 pounds of waste for each gallon of fuel. If a typical person uses 20 gallons a week, then you've got roughly 190 lbs waste needed just to produce this energy.
Add to that the fuel required to heat your home. That's another 1000 gallons/year, so now we're up another 182 lbs/week. If you're generous, let's say that the fuel efficiency doubles and homes go to solar heating for 75% of their needs. Now you're at 190/2 + 182/4 = 140lbs/week => 15 gallons/oil per person for driving and heating. Multiply this by 294 million people in the us, divide by 4 to be generous and say that each family will use this amount of fuel and you get a little over 1 Billion gallons of oil per week.
If you perfectly recycled everything you ate and threw away, you'd still fall far short of energy parity.
And those fields? Of corn/hemp/soybeans/turkeys? You're still looking at needing many pounds per week per person. How many pounds of net energy matter can an acre produce per year?
Any way you slice it, we're living on borrowed energy. Those billion barrels of oil per week supply lots of energy compared with fields of turkeys and other biomass.
The only sustainable long term solutions are:
1 - greatly reduce our consumption of non-renewable energy sources
2 - recycle 100% of all waste matter
3 - use 100% renewable sources for almost all power sources (home power, ground transportation)
well, I Googled and found one reference that says:
In California over 500,000 acres of rice are grown each year. Each acre produces 1-2.5 tons of rice straw which have been until now burned. Alternative methods of disposal are needed, and conversion to ethanol has been under development for several years. There are currently two projects underway proposing to use rice straw: one in California (Gridley) and one in Jennings, LA. If the Gridley project is fully implemented, it will add 25 million gallons of production to California's already-thin 9 million gallons per year. Barriers include collection costs and the high silica content (13%) of rice straw.
Other agricultural wastes include orchard trimmings, walnut and almond shells, and food processing wastes, for a total of about 700 MGY potential if ALL agricultural wastes were used. This is, of course, impractical, as some must be returned to the soil somehow, plus collection and transport costs will have an effect on viability of a particular waste product. Agricultural waste has the potential to satisfy a significant share of demand, with many factors to be considered when proposing a bio-refinery based on any feedstock, which are determined by full life-cycle analysis.
If 25% of the available material were used, about 175 million gallons per year could be produced.
That's good for less than one day of the country's oil consumption.
I still think that the technology is a great thing, since it puts all these waste products to good use, but I don't believe that, it is going to allow the U.S. to free itself from foreign oil any time in the near future.
Could you give a reference to support your statement that "californias agricultural waste which is mostly funneled down into a southern californian dessert lake area could supply enough fuel to satiate the US oil supply." I find that extremely difficult to believe. Based on US governemnt stats, we used 262 million gallons of oil PER DAY in 1998. That's a couple billion pounds/day. Even if the process is 80% efficient, you're talking about about 2.5 billion pounds of oil rich waste processed per day to supply the country's oil needs. That's 10 pounds for every person in the U.S. per day. If I've done my calculations correctly, than that amounts to about 1.25 million cubic meters of sludge every day. or roughly 1 square kilometer, one meter deep. If your stats are correct, they're simply astounding (and really gross!)