EC2 doesn't run your services for you; it simply gives you "dumb", unmanaged virtual machines to do whatever you want with.
I'm well aware of that.:) Indeed, that's what I'm looking for. My questions are on how persistent disk space works with EC2, not whether or not they serve your applications for you. I assume that you get some sort of disk image for free which gets loaded when an instance starts up, but if you want read-write or more space than you start with, you have to use S3FS or something similar?
Also, if anyone has any scalable postgres hosting options they could recommend, I would appreciate that.
I'm not sure how you define optimum, but it sure as hell isn't safe.
False. Tadpole-configuration with the CG just behind the front wheels is just as safe as a conventional four-wheeled approach (unless you're driving backward at high speeds).
Thanks for the link; I'm in the market for hosting. However, that link really threw me for a loop (I had been strongly leaning toward EC2) until I noticed something about their study. A potentially really big issue. They're talking about how much performance you get for your money... but they apparently chose Amazon's worst performance option -- only one compute unit (their best buy on performance is a 20 compute unit instance). That's 20x the performance for only about 8x the price. If you were going for performance, you'd never pick the cheapest option. Furthermore, EC2 prices are dramatically slashed if you put money down -- nearly in third. But they compared it to no-money-down offerings. After taking that into account, I still think I prefer EC2 over other options. That, and the linode offerings seem to have very limited disk space.
I am a bit confused about how disk space works with the Amazon EC2 cloud. They advertise how much local storage there is per instance... but then later they mention that this isn't persistent. Anyone know how persistent storage works with them? I'm also not quite sure on how they decide to use more or fewer instances. Our service fluctuates greatly in demand -- upon a user request, demand can spike tremendously for 10 seconds or so, then drop to nearly nothing until the next user request comes in. I assume they always keep at least once instance running so that the service stays alive, right? What about running a database -- our app queries a postgres DB. We certainly wouldn't want multiple copies running and going up and down. So I'm still a big vague on some of these things.
Even if you get all of the SUVs off the road, there are still semis and buses. Even if you get semis and buses off the road, there are still large, heavy inanimate objects (bridge supports, trees, culverts, etc).
Bikes are not a substitute for a car. Rain, snow, ice, cargo capacity, passenger capacity, safety, speed, etc as just a few examples. A non-shelled bike has as much drag as the much larger Aptera -- bike drag coefficients suck, and they only get by on having a small cross section. And non-ebikes are bad because they require the extremely environmentally costly energy conversion method, copious amounts of light + copious amounts of water + copious amounts of fertilizer + copious amounts of land -> small amount of food energy -> inefficiently converted to mechanical energy. Again, the only way that bikes aren't as bad for the environment as the horribly inefficient conversion would suggest is simply how small and light they are -- which comes at the downside of low speeds, no safety, tiny cargo capacity, single passenger, no protection from the elements, etc, etc.
Current vehicles aren't anywhere near fully optimized, mass-wise or aerodynamics-wised. They're still largely built out of steel (composites can be as much as nearly an order of magnitude better in terms of passenger protection per unit mass -- plus, they can't pin you in). We *still* don't generally shroud the tires (and many cars have overly large wheel wells to boot). Most cars have a sharp kink between the windshield and the hood, as well as around the A-pillars. The hood is too long and the rear end too short. There's not *nearly* enough rear taper. We do all sorts of un-aerodynamic ridiculous grill styling, when most of the air for the engine of a modern car comes from underneath anyway. Most cars still don't have aero belly pans. Many include stupid things like fake (or even worse, real) spoilers. Most cars still use *way* overweight wiring harnesses, rather than an aircraft-style networked communication system. The rear wheels are spaced way too far apart (optimum is a single rear wheel). I could go on and on. Heck, only a small fraction of cars are even hybrids.
With current tech, we could make a reasonably affordable 5-person sedan that gets ~70mpg, four-person that gets ~90, three-person that gets ~110, two-person side-by-side that gets ~130, and two-person tandem that gets ~150+, with all of the normal car comfort and safety features. But it'd mean having to first redo our production infrastructure for composites and throw our conventions of what cars *should* look like out the window.
To further the debate, however, there are several key issues running counter to what you say.
1) There are *always* heavier things than you on the road. You think your Hummer is tough? Try running into a school bus. Of course, if you think your school bus is tough, try running into an embankment.
2) The results of an uneven-weight crash can be counter-intuitive. For example, picture 6,000lb SUV A running into 3,000lb Car B head-on, each going 30mph, in an inelastic collision (I.e., assuming that they fuse on impact). What's the result of the collision? The mass A-B moving along at 10mph in the direction A was moving. Now picture 6,000lb SUV A hitting 1,500lb ultralight C under the same conditions. The result is the mass A-C moving along in the direction A was moving at 18mph. So B decelerated by 40mph, and C decelerated by 48mph -- only a 12% difference in deceleration, despite C being half the weight of B.
3) Many factors are as important or more important than mass, including but not limited to: deceleration length (how far is the safety cell from the impact point?), safety cell integrity, quality of the crumple zone, and internal safety features like airbags.
4) Vehicle crash statistics bear this all out; there is a *lot* more difference in safety within a class of vehicles than between classes.
Reminds me of a hypermiling competition I read about a good while ago. The team that won totalled the competition... by cheating.;) They built a wheeled plexiglass box (without a bottom), big enough for their car to be inside with extra room in all directions (esp. front and back). They then had a truck tow the box down the highway while they drove their car inside it at the same speed. No wind resistance!;)
The problem is, "making it roadworthy" will ruin their numbers. Let's go into the gory details, shall we?
First off, take a look at those front wheels. Notice something? How about *a lack of ability to make relevant turns*? Note that it only holds one passenger, and that's being generous. Not even the slightest bit of comfort or safety features. It's rolling along on overinflated bicycle tires. And it gets its performance at speeds where aerodynamic drag is basically zero, with no stops and starts.
In short, you simply cannot get numbers anything like that in any sort of realistic driving.
If you want to see what sort of mileage you can get in a semi-normal vehicle, the Aptera 2e is probably as good a case study as you can get. It's also a case study of a board of directors ruining a company by bringing in a lousy leadership team, but that's neither here nor there. The idea was to get two people and a reasonable amount of cargo around in a comfortable, affordable vehicle with as little energy as possible and without sacrifice to safety. To do this, they threw all *normal* conventions of style and what a vehicle should be out the window and let physics optimize it. The drag coefficient clocked in at 0.15 -- not much more than this vehicle (but with all of the things needed for "normal" vehicles, such as stability and the ability to make sharp turns and the like). But to hold two people in comfort and carry a reasonable amount of cargo, the cross sectional area has to be *way* bigger. Not as big as many cars, but still way bigger than this. Also, the affordability requirement led them to use a fiberglass/VE/foam core structure instead of carbon fiber/epoxy/foam core, which would be a little lighter. The notably larger size meant notably more total material, and the need for the ability to survive crashes and rollovers increased it still. Nonetheless, the shell was only a fraction of the 1500 pounds that the vehicle ended up at. The Aptera team tried to trim weight everywhere possible -- even using an aircraft-style wiring harness. But all of the subsystems we demand in a vehicle led the weight to grow. Also, the battery pack (since it's electric) added a couple hundred pounds, although not nearly as much as the pack in most EVs (due to the efficiency). The gasoline vehicle would be lighter, but not as much as you might expect if you want it to actually be able to have even *remotely* acceptable performance; small ICEs kind of suck in terms of power output (as well as running worse)
Anyway, all in all, the vehicle ended up being able to do 120 miles at a steady 55mph on ~10kWh. That's nearly three times as efficient as a Prius. The plug-in hybrid version was predicted to average 130mpg combined in charge-sustaining mode.
Since then, under the new management a lot of the streamlining and weight reduction has been thrown out the window, and its energy use keeps creeping up -- although still nothing like a normal car. And now the company is nearly broke, since the new CEO hasn't raised a dime in the past year and a half (unlike the old team, which raised over $30m). A tragic end to an amazing vehicle.
So, when you see these claims of thousands of MPGs, look at the Aptera as an example of what happens when you try to turn such a vehicle into a real car. What could be improved over the Aptera design? Not much, but there are some things. You could use carbon fiber and epoxy, but your costs will be higher. You could use a tandem two-seater, but not only could you not sit next to each other, but it'd mean giving up most of your storage space. You could make the passengers lean back further to reduce frontal area, but that will reduce cargo area and make the passengers less comfortable -- same with making the body narrower. You could have suppliers make ultralight versions of all of the "comfort" hardware (and safety hardware) needed for a real car, but you better have a huge budget for all of that tooling. There are small tweaks here and there you could make to t
I just look forward to the day when I no longer keep having these strange dreams of prospecting, stealing, crusading, and combat. My friends kept asking me why I've engraved "Elbereth" all over my house. All I could usually manage is to shakingly point at the water fountain outside and say, "The ampersand... it came from there!"
I figure that this pine wand that I'm whittling should give me about a 60% chance of getting out of this padded cell, depending on what type it turns out to be.
So? The CO difference between propane and gasoline is generally only 20-40% (the real improvement over gasoline is in PM, just so you know). Either way, you're talking dangerous levels.
Do you want to harvest existing algae -- the basis of most marine food chains -- or fertilize to create new algae, with possible downstream consequences?
If you think runoff from land-based farms is bad... the ocean is *all* runoff. If farming the oceans is done, it needs to be approached very slowly and carefully.
by wisdom_brewing (557753) writes: Alter Relationship on 03:30 PM -- Tuesday February 16 2010 (#31160516) CO builds up in the blood binding to red blood cells until they die
First off, even that mechanism you described is wrong. It doesn't kill red blood cells any more than it does other cells. It binds with hemoglobin instead of oxygen causing hypoxia.
However, that's only one of the ways it kills you, and that particular way is one of the short-term toxicity effects, not the chronic toxicity effects. The primary chronic effects are lipid peroxidation causing loss of white matter and necrosis in the brain.
the concentration in the air will be much lower than in... say... cigarette smoke, orders of magnitude lower.
A room heavily polluted with cigarette smoke will contain about 20ppm CO. This particular skating rink was measured at over 90ppm due to zamboni usage, with readings as high as 500ppm from the machines themselves. The NIOSH-recommended level is an 8-hour TWA of 35ppm with a 200ppm ceiling limit.
Wikipedia is your friend.:) It's actually a somewhat broad category, so to more precisely describe "1000 Reels" by The Timeout Drawer, one could say it's ambient-electric guitar-electronica that slowly builds from a simplistic, mildly atonal riff up to a theatrical crescendo, with vocals used as an instrument.
A quick google search reveals that, yes, health risks at hockey arenas from ice resurfacers are a big issue that has been studied in the medical literature. Yeah, a lot of the cases are from malfunctioning machines, but others aren't. Either way, what's your solution to make a device as complicated as an internal combustion engine never malfunction again?
Yes. OTOH, a lot of power is lost during transport from the central plant to the consuming device.
Score 4, Insightful? Sorry, but electricity transmission in the US averages 92.8% efficient.
anything else is just shifting from local pollution to remote pollution
Making pollution more remote *is* a good thing. Many pollutants have relatively short atmospheric lifespans. The further they are from people on average and the higher altitude they're emitted at, the better. Furthermore, power plants are more efficient than ICEs. And they have big, central scrubbers. And only half of our power in the US is coal (less elsewhere); the next leading sources are nuclear, natural gas, hydro, and wind. And coal's share is falling.
Indeed, that's why Aerovironment and a couple other companies have been pushing solutions for rapid-charging forklift batteries. It reduces worker time and risk of injuries when compared to battery swapping.
And if we're thinking of the children, how about thinking about all the children in places like India that become dumping grounds for the waste produced by the "green" electronic technologies?
You're thinking of computers, which generally aren't considered "green". This zamboni most likely either runs on PbA batteries or one of the "stable" li-ion variants. PbA batteries are nearly universally recycled, generally at home here in the US; they're the most recycled product on the planet. The stable li-ion variants are nontoxic; in many municipalities, you can legally just throw them in with municipal waste after discharging them.
Are you referring to the drivetrain? An AC induction motor is windings of aluminum or copper with an aluminum or copper rotor and an aluminum stator. Which will almost certainly be recycled when scrapped. A DC motor will additionally tend to use rare-earth magnets, which in addition to being nontoxic will likely be ground-up and recast at end-of-life. There are other electric components, such as the charger and inverter, but we're talking high-power hardware like silicon carbide thyristors, not high-performance CPUs that contain every other toxic metal known to man.
Computer "recycling" in the third world involves shipping masses of computers over there, lighting them on fire to burn the plastic (releasing all sorts of horrible compounds in the process), then sifting through the scrap for gold, copper, etc. Nothing like that would or even could be applied to most bulk EV hardware.
The smart, CHEAP way to slap a propane surfacer on the ass and call it Green would have been to tweak it to run on compressed hydrogen for the duration of the event and have a truckload of spare cylinders ready to go, even better if they are on a snazzy Green cart.
You could call that green, but it wouldn't be. You'd just be wasting part of the energy of the natural gas that was used to make the hydrogen, and then wasting more energy compressing it and transporting it in big, heavy, low-capacity cylinders.
And if the answer is "electrolysis hydrogen" and "fuel cells, not only is it way more expensive, but it's about 1/3rd as efficient as just storing the electricity in batteries and using it directly.
They also forget to include the carbon cost of creating the more expensive machine. Generally, the cost of a thing is roughly proportional to the energy input that it takes to make it,
Riiiight. So China, who makes steel less efficiently than they do in the US, sells it for more than we do, right?;)
Propane Zambonis are emitting CO, but this isn't generally considered a pollutant or irritant like gasoline engine exhaust (yes, yes, in can still kill you, especially if your ice rink is only 500 sq. ft.)
So your argument is, "it can kill you, but who cares"? Carbon monoxide is a chronic cardio/neurotoxin. The damage it does is permanent, and it can build up over time from exposure to even very low levels of CO that don't pose a risk of imminent death. Reducing your exposure to CO is always a good thing.
Propane is indeed cleaner burning than gasoline, but it's hardly pollution free.
ALSO, you people are forgetting to mention the carbon footprint the electric one has: is it's power source a petro power station? Or a coal power station? Those cases would make the electric one worse.
No. According to a DOE study, switching vehicles over to electric would only increase particulate matter. SOx would remain about the same, NOx would decline somewhat, and CO and VOCs would be virtually eliminated. Furthermore, all pollutants would be emitted much further from people on average. CO2 would decline by... if I remember right, 27%.
And Vancouver primarily runs on hydro anyway.
(if not worse in the case of CFL bulbs)
What's wrong with CFLs? You could use a CFL over its lifespan, then vaporize all of the mercury from it straight into the jet stream, and you'd still have emitted less mercury into the atmosphere than a coal power plant would have emitted running incandescents during that time. And furthermore:
* Mercury is just one pollutant of many that coal power plants emit. Not even near their worst.
* Coal plants emit "organic" mercury (methylmercury, dimethylmercury, etc), which is much more toxic than the elemental mercury found in CFLs.
* CFLs don't release all of their mercury when disposed of. If incinerated, about 1/4th of their mercury ends up in the environment. If recycled or landfilled, about 3% ends up in the environment. And if treated as hazardous waste, a negligible percent of the mercury ends up in the environment.
How well will it's battery pack last for those 29000 resurfacing? I wouldn't be terribly surprised if it looses much of it's capacity and needs to be replaced well before it's completed all of them. And that battery pack is the most expensive thing on the resurfacing machine...
It depends, and not necessarily. I imagine it's a DC drive with a relatively meager charger, so the pack cost/drivetrain cost ratio is probably relatively high (most people would be surprised at how low it is for modern EVs -- most people think the packs are more expensive than they are and the drivetrains cheaper than they are). If the pack is PbA, it'll need to be replaced once every 3-5 years. If it's LFP or LiMnO4 (the "stable" types of li-ion), it should be good for closer to 10 years, so long as the DoD (Depth of Discharge) is kept reasonable.
One thing people haven't been mentioning is how much lower maintenance the drivetrain is in an EV than in an ICE-powered vehicle. There's something like 1/10th as many moving parts.
As for these particular machines... bad development and testing is bad development and testing, no matter what type of powertrain your vehicle has.
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EC2 doesn't run your services for you; it simply gives you "dumb", unmanaged virtual machines to do whatever you want with.
I'm well aware of that. :) Indeed, that's what I'm looking for. My questions are on how persistent disk space works with EC2, not whether or not they serve your applications for you. I assume that you get some sort of disk image for free which gets loaded when an instance starts up, but if you want read-write or more space than you start with, you have to use S3FS or something similar?
Also, if anyone has any scalable postgres hosting options they could recommend, I would appreciate that.
I'm not sure how you define optimum, but it sure as hell isn't safe.
False. Tadpole-configuration with the CG just behind the front wheels is just as safe as a conventional four-wheeled approach (unless you're driving backward at high speeds).
Thanks for the link; I'm in the market for hosting. However, that link really threw me for a loop (I had been strongly leaning toward EC2) until I noticed something about their study. A potentially really big issue. They're talking about how much performance you get for your money... but they apparently chose Amazon's worst performance option -- only one compute unit (their best buy on performance is a 20 compute unit instance). That's 20x the performance for only about 8x the price. If you were going for performance, you'd never pick the cheapest option. Furthermore, EC2 prices are dramatically slashed if you put money down -- nearly in third. But they compared it to no-money-down offerings. After taking that into account, I still think I prefer EC2 over other options. That, and the linode offerings seem to have very limited disk space.
I am a bit confused about how disk space works with the Amazon EC2 cloud. They advertise how much local storage there is per instance... but then later they mention that this isn't persistent. Anyone know how persistent storage works with them? I'm also not quite sure on how they decide to use more or fewer instances. Our service fluctuates greatly in demand -- upon a user request, demand can spike tremendously for 10 seconds or so, then drop to nearly nothing until the next user request comes in. I assume they always keep at least once instance running so that the service stays alive, right? What about running a database -- our app queries a postgres DB. We certainly wouldn't want multiple copies running and going up and down. So I'm still a big vague on some of these things.
Even if you get all of the SUVs off the road, there are still semis and buses.
Even if you get semis and buses off the road, there are still large, heavy inanimate objects (bridge supports, trees, culverts, etc).
Bikes are not a substitute for a car. Rain, snow, ice, cargo capacity, passenger capacity, safety, speed, etc as just a few examples. A non-shelled bike has as much drag as the much larger Aptera -- bike drag coefficients suck, and they only get by on having a small cross section. And non-ebikes are bad because they require the extremely environmentally costly energy conversion method, copious amounts of light + copious amounts of water + copious amounts of fertilizer + copious amounts of land -> small amount of food energy -> inefficiently converted to mechanical energy. Again, the only way that bikes aren't as bad for the environment as the horribly inefficient conversion would suggest is simply how small and light they are -- which comes at the downside of low speeds, no safety, tiny cargo capacity, single passenger, no protection from the elements, etc, etc.
Current vehicles aren't anywhere near fully optimized, mass-wise or aerodynamics-wised. They're still largely built out of steel (composites can be as much as nearly an order of magnitude better in terms of passenger protection per unit mass -- plus, they can't pin you in). We *still* don't generally shroud the tires (and many cars have overly large wheel wells to boot). Most cars have a sharp kink between the windshield and the hood, as well as around the A-pillars. The hood is too long and the rear end too short. There's not *nearly* enough rear taper. We do all sorts of un-aerodynamic ridiculous grill styling, when most of the air for the engine of a modern car comes from underneath anyway. Most cars still don't have aero belly pans. Many include stupid things like fake (or even worse, real) spoilers. Most cars still use *way* overweight wiring harnesses, rather than an aircraft-style networked communication system. The rear wheels are spaced way too far apart (optimum is a single rear wheel). I could go on and on. Heck, only a small fraction of cars are even hybrids.
With current tech, we could make a reasonably affordable 5-person sedan that gets ~70mpg, four-person that gets ~90, three-person that gets ~110, two-person side-by-side that gets ~130, and two-person tandem that gets ~150+, with all of the normal car comfort and safety features. But it'd mean having to first redo our production infrastructure for composites and throw our conventions of what cars *should* look like out the window.
To further the debate, however, there are several key issues running counter to what you say.
1) There are *always* heavier things than you on the road. You think your Hummer is tough? Try running into a school bus. Of course, if you think your school bus is tough, try running into an embankment.
2) The results of an uneven-weight crash can be counter-intuitive. For example, picture 6,000lb SUV A running into 3,000lb Car B head-on, each going 30mph, in an inelastic collision (I.e., assuming that they fuse on impact). What's the result of the collision? The mass A-B moving along at 10mph in the direction A was moving. Now picture 6,000lb SUV A hitting 1,500lb ultralight C under the same conditions. The result is the mass A-C moving along in the direction A was moving at 18mph. So B decelerated by 40mph, and C decelerated by 48mph -- only a 12% difference in deceleration, despite C being half the weight of B.
3) Many factors are as important or more important than mass, including but not limited to: deceleration length (how far is the safety cell from the impact point?), safety cell integrity, quality of the crumple zone, and internal safety features like airbags.
4) Vehicle crash statistics bear this all out; there is a *lot* more difference in safety within a class of vehicles than between classes.
Reminds me of a hypermiling competition I read about a good while ago. The team that won totalled the competition... by cheating. ;) They built a wheeled plexiglass box (without a bottom), big enough for their car to be inside with extra room in all directions (esp. front and back). They then had a truck tow the box down the highway while they drove their car inside it at the same speed. No wind resistance! ;)
The problem is, "making it roadworthy" will ruin their numbers. Let's go into the gory details, shall we?
First off, take a look at those front wheels. Notice something? How about *a lack of ability to make relevant turns*? Note that it only holds one passenger, and that's being generous. Not even the slightest bit of comfort or safety features. It's rolling along on overinflated bicycle tires. And it gets its performance at speeds where aerodynamic drag is basically zero, with no stops and starts.
In short, you simply cannot get numbers anything like that in any sort of realistic driving.
If you want to see what sort of mileage you can get in a semi-normal vehicle, the Aptera 2e is probably as good a case study as you can get. It's also a case study of a board of directors ruining a company by bringing in a lousy leadership team, but that's neither here nor there. The idea was to get two people and a reasonable amount of cargo around in a comfortable, affordable vehicle with as little energy as possible and without sacrifice to safety. To do this, they threw all *normal* conventions of style and what a vehicle should be out the window and let physics optimize it. The drag coefficient clocked in at 0.15 -- not much more than this vehicle (but with all of the things needed for "normal" vehicles, such as stability and the ability to make sharp turns and the like). But to hold two people in comfort and carry a reasonable amount of cargo, the cross sectional area has to be *way* bigger. Not as big as many cars, but still way bigger than this. Also, the affordability requirement led them to use a fiberglass/VE/foam core structure instead of carbon fiber/epoxy/foam core, which would be a little lighter. The notably larger size meant notably more total material, and the need for the ability to survive crashes and rollovers increased it still. Nonetheless, the shell was only a fraction of the 1500 pounds that the vehicle ended up at. The Aptera team tried to trim weight everywhere possible -- even using an aircraft-style wiring harness. But all of the subsystems we demand in a vehicle led the weight to grow. Also, the battery pack (since it's electric) added a couple hundred pounds, although not nearly as much as the pack in most EVs (due to the efficiency). The gasoline vehicle would be lighter, but not as much as you might expect if you want it to actually be able to have even *remotely* acceptable performance; small ICEs kind of suck in terms of power output (as well as running worse)
Anyway, all in all, the vehicle ended up being able to do 120 miles at a steady 55mph on ~10kWh. That's nearly three times as efficient as a Prius. The plug-in hybrid version was predicted to average 130mpg combined in charge-sustaining mode.
Since then, under the new management a lot of the streamlining and weight reduction has been thrown out the window, and its energy use keeps creeping up -- although still nothing like a normal car. And now the company is nearly broke, since the new CEO hasn't raised a dime in the past year and a half (unlike the old team, which raised over $30m). A tragic end to an amazing vehicle.
So, when you see these claims of thousands of MPGs, look at the Aptera as an example of what happens when you try to turn such a vehicle into a real car. What could be improved over the Aptera design? Not much, but there are some things. You could use carbon fiber and epoxy, but your costs will be higher. You could use a tandem two-seater, but not only could you not sit next to each other, but it'd mean giving up most of your storage space. You could make the passengers lean back further to reduce frontal area, but that will reduce cargo area and make the passengers less comfortable -- same with making the body narrower. You could have suppliers make ultralight versions of all of the "comfort" hardware (and safety hardware) needed for a real car, but you better have a huge budget for all of that tooling. There are small tweaks here and there you could make to t
the company Second Sight promises to commercialize the implant, aiming for VGA resolution within the decade.
And, if they achieve VGA resolution, you can just get the next upgrade in software!
I just look forward to the day when I no longer keep having these strange dreams of prospecting, stealing, crusading, and combat. My friends kept asking me why I've engraved "Elbereth" all over my house. All I could usually manage is to shakingly point at the water fountain outside and say, "The ampersand... it came from there!"
I figure that this pine wand that I'm whittling should give me about a 60% chance of getting out of this padded cell, depending on what type it turns out to be.
I don't know... it'd kind of suck if life got too close to being like a video game. ;)
So? The CO difference between propane and gasoline is generally only 20-40% (the real improvement over gasoline is in PM, just so you know). Either way, you're talking dangerous levels.
Do you want to harvest existing algae -- the basis of most marine food chains -- or fertilize to create new algae, with possible downstream consequences?
If you think runoff from land-based farms is bad... the ocean is *all* runoff. If farming the oceans is done, it needs to be approached very slowly and carefully.
by wisdom_brewing (557753) writes: Alter Relationship on 03:30 PM -- Tuesday February 16 2010 (#31160516)
CO builds up in the blood binding to red blood cells until they die
First off, even that mechanism you described is wrong. It doesn't kill red blood cells any more than it does other cells. It binds with hemoglobin instead of oxygen causing hypoxia.
However, that's only one of the ways it kills you, and that particular way is one of the short-term toxicity effects, not the chronic toxicity effects. The primary chronic effects are lipid peroxidation causing loss of white matter and necrosis in the brain.
the concentration in the air will be much lower than in... say... cigarette smoke, orders of magnitude lower.
A room heavily polluted with cigarette smoke will contain about 20ppm CO. This particular skating rink was measured at over 90ppm due to zamboni usage, with readings as high as 500ppm from the machines themselves. The NIOSH-recommended level is an 8-hour TWA of 35ppm with a 200ppm ceiling limit.
Space Rock is a genre of music?
Wikipedia is your friend. :) It's actually a somewhat broad category, so to more precisely describe "1000 Reels" by The Timeout Drawer, one could say it's ambient-electric guitar-electronica that slowly builds from a simplistic, mildly atonal riff up to a theatrical crescendo, with vocals used as an instrument.
That detailed enough? :)
A quick google search reveals that, yes, health risks at hockey arenas from ice resurfacers are a big issue that has been studied in the medical literature. Yeah, a lot of the cases are from malfunctioning machines, but others aren't. Either way, what's your solution to make a device as complicated as an internal combustion engine never malfunction again?
Yes. OTOH, a lot of power is lost during transport from the central plant to the consuming device.
Score 4, Insightful? Sorry, but electricity transmission in the US averages 92.8% efficient.
anything else is just shifting from local pollution to remote pollution
Making pollution more remote *is* a good thing. Many pollutants have relatively short atmospheric lifespans. The further they are from people on average and the higher altitude they're emitted at, the better. Furthermore, power plants are more efficient than ICEs. And they have big, central scrubbers. And only half of our power in the US is coal (less elsewhere); the next leading sources are nuclear, natural gas, hydro, and wind. And coal's share is falling.
Indeed, that's why Aerovironment and a couple other companies have been pushing solutions for rapid-charging forklift batteries. It reduces worker time and risk of injuries when compared to battery swapping.
What a moron, siding with 97% of active, publishing climate scientists.
And if we're thinking of the children, how about thinking about all the children in places like India that become dumping grounds for the waste produced by the "green" electronic technologies?
You're thinking of computers, which generally aren't considered "green". This zamboni most likely either runs on PbA batteries or one of the "stable" li-ion variants. PbA batteries are nearly universally recycled, generally at home here in the US; they're the most recycled product on the planet. The stable li-ion variants are nontoxic; in many municipalities, you can legally just throw them in with municipal waste after discharging them.
Are you referring to the drivetrain? An AC induction motor is windings of aluminum or copper with an aluminum or copper rotor and an aluminum stator. Which will almost certainly be recycled when scrapped. A DC motor will additionally tend to use rare-earth magnets, which in addition to being nontoxic will likely be ground-up and recast at end-of-life. There are other electric components, such as the charger and inverter, but we're talking high-power hardware like silicon carbide thyristors, not high-performance CPUs that contain every other toxic metal known to man.
Computer "recycling" in the third world involves shipping masses of computers over there, lighting them on fire to burn the plastic (releasing all sorts of horrible compounds in the process), then sifting through the scrap for gold, copper, etc. Nothing like that would or even could be applied to most bulk EV hardware.
The smart, CHEAP way to slap a propane surfacer on the ass and call it Green would have been to tweak it to run on compressed hydrogen for the duration of the event and have a truckload of spare cylinders ready to go, even better if they are on a snazzy Green cart.
You could call that green, but it wouldn't be. You'd just be wasting part of the energy of the natural gas that was used to make the hydrogen, and then wasting more energy compressing it and transporting it in big, heavy, low-capacity cylinders.
And if the answer is "electrolysis hydrogen" and "fuel cells, not only is it way more expensive, but it's about 1/3rd as efficient as just storing the electricity in batteries and using it directly.
They also forget to include the carbon cost of creating the more expensive machine. Generally, the cost of a thing is roughly proportional to the energy input that it takes to make it,
Riiiight. So China, who makes steel less efficiently than they do in the US, sells it for more than we do, right? ;)
Propane Zambonis are emitting CO, but this isn't generally considered a pollutant or irritant like gasoline engine exhaust (yes, yes, in can still kill you, especially if your ice rink is only 500 sq. ft.)
So your argument is, "it can kill you, but who cares"? Carbon monoxide is a chronic cardio/neurotoxin. The damage it does is permanent, and it can build up over time from exposure to even very low levels of CO that don't pose a risk of imminent death. Reducing your exposure to CO is always a good thing.
Propane is indeed cleaner burning than gasoline, but it's hardly pollution free.
ALSO, you people are forgetting to mention the carbon footprint the electric one has: is it's power source a petro power station? Or a coal power station? Those cases would make the electric one worse.
No. According to a DOE study, switching vehicles over to electric would only increase particulate matter. SOx would remain about the same, NOx would decline somewhat, and CO and VOCs would be virtually eliminated. Furthermore, all pollutants would be emitted much further from people on average. CO2 would decline by... if I remember right, 27%.
And Vancouver primarily runs on hydro anyway.
(if not worse in the case of CFL bulbs)
What's wrong with CFLs? You could use a CFL over its lifespan, then vaporize all of the mercury from it straight into the jet stream, and you'd still have emitted less mercury into the atmosphere than a coal power plant would have emitted running incandescents during that time. And furthermore:
* Mercury is just one pollutant of many that coal power plants emit. Not even near their worst.
* Coal plants emit "organic" mercury (methylmercury, dimethylmercury, etc), which is much more toxic than the elemental mercury found in CFLs.
* CFLs don't release all of their mercury when disposed of. If incinerated, about 1/4th of their mercury ends up in the environment. If recycled or landfilled, about 3% ends up in the environment. And if treated as hazardous waste, a negligible percent of the mercury ends up in the environment.
How well will it's battery pack last for those 29000 resurfacing? I wouldn't be terribly surprised if it looses much of it's capacity and needs to be replaced well before it's completed all of them. And that battery pack is the most expensive thing on the resurfacing machine...
It depends, and not necessarily. I imagine it's a DC drive with a relatively meager charger, so the pack cost/drivetrain cost ratio is probably relatively high (most people would be surprised at how low it is for modern EVs -- most people think the packs are more expensive than they are and the drivetrains cheaper than they are). If the pack is PbA, it'll need to be replaced once every 3-5 years. If it's LFP or LiMnO4 (the "stable" types of li-ion), it should be good for closer to 10 years, so long as the DoD (Depth of Discharge) is kept reasonable.
One thing people haven't been mentioning is how much lower maintenance the drivetrain is in an EV than in an ICE-powered vehicle. There's something like 1/10th as many moving parts.
As for these particular machines... bad development and testing is bad development and testing, no matter what type of powertrain your vehicle has.