In my experiences dealing with photovoltaic power supply systems of all sizes, I've become convinced that solar panels are currently not a viable solution for powering mobile devices for a few reasons, mainly cost, unreliability, and inefficiency.
First of all, look at how much these things cost. the Portable Power Pack retails online for 420 pounds, or about $660. You could buy more than a dozen eeepc batteries for that much and just keep them stocked in your car or rucksack or whatever. LiIon batteries aren't terrible for the environment, and you won't even need sun to use them...
Speaking of the sun, I live in beautiful southern California, where one can definitely count on the sun 99% of the time. But most parts of the world aren't that sunny, and even if the sun is shining there's bound to be a tree/building/civilization in the way just when you need it most. You're not going to walk or drive around the city looking for a nice open space to sit in for an hour and roast while you check your email, just so you could feel good about spending $600 on a solar panel, no matter how good your intentions are.
so how do you charge your devices with a solar panel while actually "on the go"? you can try to drape it over that rucksack of yours while you're walking somewhere, but if the panel isn't facing the sun directly you won't get anywhere near the peak power output advertised. Instead, you need to find an open space and lay out your few-square-foot mat-- and then you're tied to the ground.
And what about that generous peak power they keep advertising? solar panels output their peak power when they are laid out flat, directly facing the sun, on a completely clear, sunny day. I know from personal experience with small panels that small deviations from the sun-facing angle mean big drops in power.
So alright, let's say that you bought a 30 watt panel and it's noon on a clear, sunny day, so you're getting 30 watts out of it. Please correct me if I am wrong, but I believe that EeePCs use 36 watt power adapters. How do you plan on charging and using your EeePC on less than 36 watts WHILE charging your phone and whatever else you have plugged in? all you could possibly do is increase your battery life considerably-- which might be great, but i'm not sure it justifies the costs and the effort involved.
Here's my suggestion: Save the money you were going to spend on that portable panel. Use a little to buy extra batteries for your gadgets, and put the rest in a savings account. Save up for a large, multi-kilowatt solar system for your house, which will save a lot more greenhouse gas emissions per dollar you spend than one of these portable things. Use that home solar system to charge your batteries, and you're gold... er, green.
If you read the article, it mentions that the system is designed to harvest light that is reflected off the roof of the building, which is probably being lit by the spaces between the tubes.
On that note, however, concentrating solar power systems do exist (http://en.wikipedia.org/wiki/Concentrating_solar_power#Concentrator_photovoltaics)
Note that many concentrated solar power plants don't use photovoltaic cells at all. Many just focus sunlight to boil water for a steam turbine or to run a stirling engine directly.
If this were a perfect solution, it would probably be implemented more often. My guess is that the cost and complexity of making a giant parabolic mirror, or a lot of flat tracking mirrors, outweighs the increases in efficiency. Also, imagine the maintenance costs on a field of electromechanical solar tracking mirrors or on a parabolic mirror that needs to be wiped down every so often.
Also, the chances of blinding/cooking alive passers-by with your giant parabolic mirror if your tracking system dies are probably too great for comfort.
damnit, now i want a giant parabolic mirror.
come on, how cool would that be?
I think a welded-shut steel box would fit the bill for a faraday cage.
I don't think there's much need for EEPROM. That's the stuff you can erase and rewrite, which probably won't be necessary. How about regular old-school ROM chips? you know, the kind that store data by frying traces off the die. Then your only problem would be interfacing, which wouldn't be harder than programming a USB-enabled PIC chip to work like a normal thumbdrive.
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In my experiences dealing with photovoltaic power supply systems of all sizes, I've become convinced that solar panels are currently not a viable solution for powering mobile devices for a few reasons, mainly cost, unreliability, and inefficiency.
First of all, look at how much these things cost. the Portable Power Pack retails online for 420 pounds, or about $660. You could buy more than a dozen eeepc batteries for that much and just keep them stocked in your car or rucksack or whatever. LiIon batteries aren't terrible for the environment, and you won't even need sun to use them...
Speaking of the sun, I live in beautiful southern California, where one can definitely count on the sun 99% of the time. But most parts of the world aren't that sunny, and even if the sun is shining there's bound to be a tree/building/civilization in the way just when you need it most. You're not going to walk or drive around the city looking for a nice open space to sit in for an hour and roast while you check your email, just so you could feel good about spending $600 on a solar panel, no matter how good your intentions are.
so how do you charge your devices with a solar panel while actually "on the go"? you can try to drape it over that rucksack of yours while you're walking somewhere, but if the panel isn't facing the sun directly you won't get anywhere near the peak power output advertised. Instead, you need to find an open space and lay out your few-square-foot mat-- and then you're tied to the ground.
And what about that generous peak power they keep advertising? solar panels output their peak power when they are laid out flat, directly facing the sun, on a completely clear, sunny day. I know from personal experience with small panels that small deviations from the sun-facing angle mean big drops in power.
So alright, let's say that you bought a 30 watt panel and it's noon on a clear, sunny day, so you're getting 30 watts out of it. Please correct me if I am wrong, but I believe that EeePCs use 36 watt power adapters. How do you plan on charging and using your EeePC on less than 36 watts WHILE charging your phone and whatever else you have plugged in? all you could possibly do is increase your battery life considerably-- which might be great, but i'm not sure it justifies the costs and the effort involved.
Here's my suggestion: Save the money you were going to spend on that portable panel. Use a little to buy extra batteries for your gadgets, and put the rest in a savings account. Save up for a large, multi-kilowatt solar system for your house, which will save a lot more greenhouse gas emissions per dollar you spend than one of these portable things. Use that home solar system to charge your batteries, and you're gold... er, green.
All of the replies to this thread are beginning to prove me right.
If you read the article, it mentions that the system is designed to harvest light that is reflected off the roof of the building, which is probably being lit by the spaces between the tubes.
On that note, however, concentrating solar power systems do exist (http://en.wikipedia.org/wiki/Concentrating_solar_power#Concentrator_photovoltaics) Note that many concentrated solar power plants don't use photovoltaic cells at all. Many just focus sunlight to boil water for a steam turbine or to run a stirling engine directly.
If this were a perfect solution, it would probably be implemented more often. My guess is that the cost and complexity of making a giant parabolic mirror, or a lot of flat tracking mirrors, outweighs the increases in efficiency. Also, imagine the maintenance costs on a field of electromechanical solar tracking mirrors or on a parabolic mirror that needs to be wiped down every so often.
Also, the chances of blinding/cooking alive passers-by with your giant parabolic mirror if your tracking system dies are probably too great for comfort.
damnit, now i want a giant parabolic mirror.
come on, how cool would that be?
... until somebody solders a crapload of diodes to their motherboard to drop each ram output line voltage by .7v.
Bonus points if they're LEDs.
I think a welded-shut steel box would fit the bill for a faraday cage. I don't think there's much need for EEPROM. That's the stuff you can erase and rewrite, which probably won't be necessary. How about regular old-school ROM chips? you know, the kind that store data by frying traces off the die. Then your only problem would be interfacing, which wouldn't be harder than programming a USB-enabled PIC chip to work like a normal thumbdrive.