Wireless Energy Lights Bulb from Seven Feet Away: Scientific American
The idea of not having to deal with a power cord for recharging portable devices has appeal, but it's an example of where government regulation has a role.
On the MIT tabletop, this system of energy transfer is only 40 percent efficient, meaning that it takes more than twice the energy to do the job a power cord would do (reasonably assuming that resistive losses in the power cord, though non-zero, are negligible).
Efficiency will improve somewhat (possibly to as much as 70 percent) by the time this sort of product is generally available, but that still represents a large energy premium, especially when you include significant upstream losses. Considering the large number of portable devices out there, that's a lot of coal burned and CO2 emitted. It's an unnecessary load on an already overloaded national energy grid. It's the wrong way to go.
We live in an age when increasing energy efficiency is critical for various reasons. Just as some jurisdictions are beginning to ban incandescent lighting, this sort of wireless powering of portable devices probably ought to be disallowed for non-essential applications.
In some applications this mode of energy transfer may make good sense, but if you believe (as I do) that humanity is rapidly (and increasingly so) trashing the atmosphere to the globe's and humanity's severe detriment, if you're in favor of wind, solar, nuclear and other atmospherically benign, renewable sources of energy, then you ought to be opposed to this development for the consumer electronics market.
Showing posts with label energy. Show all posts
Showing posts with label energy. Show all posts
Saturday, June 09, 2007
Friday, June 01, 2007
The Nuclear Temptation: The Perils of Pushing Atomic Energy as the Climate Change Panacea - International - SPIEGEL ONLINE - News
The Nuclear Temptation: The Perils of Pushing Atomic Energy as the Climate Change Panacea - International - SPIEGEL ONLINE - News
This article leaves me frustrated. There's nothing new, and the anti-nuclear slant gets old. Even the title is annoying. "... the Climate Change Panacea ..." Anybody who uncritically uses the word "panacea" in a sentence containing the phrase "climate change" ought to be shot, not only because there is no climate change panacea, but because nobody with half a brain claims that there is.
Uncritical association of "panacea" with "climate change" is suitable for setting up a straw man, and nothing more.
What might have been new would have been some sort of analysis of exactly how humanity can expect to obtain the energy needed to replace depleting energy presently liberated from polluting fossil sources, all the while providing vast quantities of new energy to meet the needs of expanding economies and many millions of new people (two or three billion of whom already exist in squalor).
But no. The question is acknowledged as pressing, but that's about it.
The article acknowledges the "largely carbon neutral" nature of nuclear energy, but only as a back-handed explanation that the fact "allows the industry to accept and promote the worst-case climate change scenarios while simultaneously presenting itself as a potential solution to the problem of global warming."
In a variant of the "panacea" fallacy, some activist doctor is paraphrased as saying that "Nuclear power simply doesn't have the ability to influence global warming decisively..."
Decisively?
Does the good doctor actually think that any option could be individually decisive? Human dieoff would be decisive, but that's not much of an option. I wonder if this doctor has considered the decisiveness of battle deaths in resource wars, the likelihood of which is some function to energy availability?
Enough.
This article leaves me frustrated. There's nothing new, and the anti-nuclear slant gets old. Even the title is annoying. "... the Climate Change Panacea ..." Anybody who uncritically uses the word "panacea" in a sentence containing the phrase "climate change" ought to be shot, not only because there is no climate change panacea, but because nobody with half a brain claims that there is.
Uncritical association of "panacea" with "climate change" is suitable for setting up a straw man, and nothing more.
What might have been new would have been some sort of analysis of exactly how humanity can expect to obtain the energy needed to replace depleting energy presently liberated from polluting fossil sources, all the while providing vast quantities of new energy to meet the needs of expanding economies and many millions of new people (two or three billion of whom already exist in squalor).
But no. The question is acknowledged as pressing, but that's about it.
The article acknowledges the "largely carbon neutral" nature of nuclear energy, but only as a back-handed explanation that the fact "allows the industry to accept and promote the worst-case climate change scenarios while simultaneously presenting itself as a potential solution to the problem of global warming."
In a variant of the "panacea" fallacy, some activist doctor is paraphrased as saying that "Nuclear power simply doesn't have the ability to influence global warming decisively..."
Decisively?
Does the good doctor actually think that any option could be individually decisive? Human dieoff would be decisive, but that's not much of an option. I wonder if this doctor has considered the decisiveness of battle deaths in resource wars, the likelihood of which is some function to energy availability?
Enough.
Sunday, March 04, 2007
Cheap Compact Fluorescent Lamps
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I've been using compact fluorescent lamps almost exclusively for ten years or more. I pay the extra price in the name of the energy efficiency that everyone claims for them. Even so, I've always been skeptical about claims of energy efficiency, especially when I start to think about the energy embedded in CFL lamps. Just looking at the two types of lamps (CFL and incandescent) I have to conclude that the energy it takes to assemble a CFL is many times greater than what it takes to make a standard incandescent bulb.
One of the reasons I've been skeptical about all this is because CFL's, in my experience, never seem to deliver the hours of service claimed by the manufacturers. I don't care how efficient a lamp may be, energy return on energy investment is compromised by poor durability (and greatly so, I think). I rather suspect that, all things considered, in the aggregate I've been using more, not less, energy by using CFLs. Who knows, though? In the summertime my air conditioner would work even harder if it had to deal with extra heat from incandescents. Maybe it's all a wash.
In the past couple of years I've taken to marking each CFL with the date it entered service in order to get a better sense of this. It's stupid, but when a CFL I've marked has failed, I generally just glanced at the date, bolstering my suspicion, and screwed in a replacement CFL.
This morning, though, I took the time to think about this a little bit.
A 26 watt (100 watt equivalent (yeah yeah, I know)) CFL that I had installed on November 9 2005 (480 days ago) failed in the bathroom. The bathroom has to be one of the more severe environments for a light bulb because of the number of on/off cycles as well as total running time. I thought about the usage pattern in that bathroom and figured that the lamp probably experienced about 15 on/off cycles per day, averaging 20 minutes or so of on time per cycle, which came to about 6 hours on per day. Over its cumulative service life of about 2880 hours, this bulb would have gone through about 75 kilowatt hours of energy, costing about $6 at 8 cents per kilowatt hour. It would have gone through about 7200 on/off cycles in the process.
Now, 2880 hours in nowhere near the lifetime claimed by CFL manufacturers. According to the EPA's Energy Star website, these things ought to last 6,000 hours or more.
Well, after a bit of looking around I found a document about durability testing of CFLs. The part that caught my eye was about stress testing, where they cycled CFLs on and off for the lamp's lifetime (five minutes on, five minutes off). What they found was that two manufacturers' lamps failed "very prematurely". Here's the relevant figure (click it for a bigger view):
I generally buy whatever CFLs Costco, Home Depot or Walmart are selling, which I assume are the cheapest things they can find. It wouldn't surprise me to find out that the lamps I buy are from the two sub-par manufacturers. I know the test cycle pattern doesn't match the usage of CFLs installed in my bathroom, but from the results of the test and my own experience, it seems reasonable to look for higher quality lamps. I'll see what the people at Lights of America have to say, and otherwise try to identify higher quality CFLs to buy. If I'm still here in a few years maybe I'll remember to post how the better lamps perform. On the other hand, maybe I'll revert to lower-wattage halogen incandescent bulbs for the bathroom. Apparently moisture can affect CFL's, so maybe I'll go with a higher-quality weatherproof CFL for the bathroom.
Should government ban incandescent bulbs, as is being done in Australia and as California is considering? Well, it seems to me highly likely that if we ban incandescents without, at the same time, banning sub-par CFLs like those in the graph above (presumably what I've been buying), it seems that such a ban would be worse, from a global perspective and considering embedded energy, than doing nothing.
I've been using compact fluorescent lamps almost exclusively for ten years or more. I pay the extra price in the name of the energy efficiency that everyone claims for them. Even so, I've always been skeptical about claims of energy efficiency, especially when I start to think about the energy embedded in CFL lamps. Just looking at the two types of lamps (CFL and incandescent) I have to conclude that the energy it takes to assemble a CFL is many times greater than what it takes to make a standard incandescent bulb.
One of the reasons I've been skeptical about all this is because CFL's, in my experience, never seem to deliver the hours of service claimed by the manufacturers. I don't care how efficient a lamp may be, energy return on energy investment is compromised by poor durability (and greatly so, I think). I rather suspect that, all things considered, in the aggregate I've been using more, not less, energy by using CFLs. Who knows, though? In the summertime my air conditioner would work even harder if it had to deal with extra heat from incandescents. Maybe it's all a wash.
In the past couple of years I've taken to marking each CFL with the date it entered service in order to get a better sense of this. It's stupid, but when a CFL I've marked has failed, I generally just glanced at the date, bolstering my suspicion, and screwed in a replacement CFL.
This morning, though, I took the time to think about this a little bit.
A 26 watt (100 watt equivalent (yeah yeah, I know)) CFL that I had installed on November 9 2005 (480 days ago) failed in the bathroom. The bathroom has to be one of the more severe environments for a light bulb because of the number of on/off cycles as well as total running time. I thought about the usage pattern in that bathroom and figured that the lamp probably experienced about 15 on/off cycles per day, averaging 20 minutes or so of on time per cycle, which came to about 6 hours on per day. Over its cumulative service life of about 2880 hours, this bulb would have gone through about 75 kilowatt hours of energy, costing about $6 at 8 cents per kilowatt hour. It would have gone through about 7200 on/off cycles in the process.
Now, 2880 hours in nowhere near the lifetime claimed by CFL manufacturers. According to the EPA's Energy Star website, these things ought to last 6,000 hours or more.
Well, after a bit of looking around I found a document about durability testing of CFLs. The part that caught my eye was about stress testing, where they cycled CFLs on and off for the lamp's lifetime (five minutes on, five minutes off). What they found was that two manufacturers' lamps failed "very prematurely". Here's the relevant figure (click it for a bigger view):
I generally buy whatever CFLs Costco, Home Depot or Walmart are selling, which I assume are the cheapest things they can find. It wouldn't surprise me to find out that the lamps I buy are from the two sub-par manufacturers. I know the test cycle pattern doesn't match the usage of CFLs installed in my bathroom, but from the results of the test and my own experience, it seems reasonable to look for higher quality lamps. I'll see what the people at Lights of America have to say, and otherwise try to identify higher quality CFLs to buy. If I'm still here in a few years maybe I'll remember to post how the better lamps perform. On the other hand, maybe I'll revert to lower-wattage halogen incandescent bulbs for the bathroom. Apparently moisture can affect CFL's, so maybe I'll go with a higher-quality weatherproof CFL for the bathroom.
Should government ban incandescent bulbs, as is being done in Australia and as California is considering? Well, it seems to me highly likely that if we ban incandescents without, at the same time, banning sub-par CFLs like those in the graph above (presumably what I've been buying), it seems that such a ban would be worse, from a global perspective and considering embedded energy, than doing nothing.
Friday, January 26, 2007
Technology Review: Battery Breakthrough?
Technology Review: Battery Breakthrough?
Well, that's certainly interesting.
Should this thing take off in the automotive sector it will have significant implications for the electricity grid. That's no biggie, as the electricity grid already faces significant issues. This'll just be one more challenge, and not the biggest one.
Even if the thing doesn't work out in the automotive arena, and if this isn't a bunch of hype (such as I've become accustomed to with flywheels over the years), and if self-discharge isn't an issue, this could be a big deal. In any event it's worth watching.
My biggest problem with the article is the final part of this sentence:
Well, that's certainly interesting.
... dramatically outperform the best lithium-ion batteries on the market in terms of energy density, price, charge time, and safety. Pound for pound, it will also pack 10 times the punch of lead-acid batteries at half the cost and without the need for toxic materials or chemicals ...And
... specific energy of about 280 watt hours per kilogram, compared with around 120 watt hours per kilogram for lithium-ion and 32 watt hours per kilogram for lead-acid gel batteries.As for a first production run,
a 15-kilowatt-hour energy-storage system for a small electric car weighing less than 100 pounds, and with a 200-mile driving range. The vehicle, the company says, will be able to recharge in less than 10 minutes.If my numbers are right that's a 90 kilowatt charge rate, several times the maximum my house uses at summer peak. Home plug-in charging will have to be throttled considerably, or dedicated charging stations will be required. The range and energy numbers imply something like 5 kilowatt drain, which may be reasonable for a small, aerodynamic car.
Should this thing take off in the automotive sector it will have significant implications for the electricity grid. That's no biggie, as the electricity grid already faces significant issues. This'll just be one more challenge, and not the biggest one.
Even if the thing doesn't work out in the automotive arena, and if this isn't a bunch of hype (such as I've become accustomed to with flywheels over the years), and if self-discharge isn't an issue, this could be a big deal. In any event it's worth watching.
My biggest problem with the article is the final part of this sentence:
Such a breakthrough has the potential to radically transform a transportation sector already flirting with an electric renaissance, improve the performance of intermittent energy sources such as wind and sun, and increase the efficiency and stability of power grids--all while fulfilling an oil-addicted America's quest for energy security.It's a battery, not an energy source, and it's not going to fulfill any quest for energy security. Maybe I'm nitpicking.
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