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Solar Power From Home Curtains
kaliann writes "With the push for more sustainable energy, easy DIY kits for alternative energy sources are likely to become quite popular in the coming years. We may see some big improvements in our ability to 'green up' if these photovoltaic curtains become widely available."
The killer app for renewable energy will be to get the cost down.
Once it makes economic sense for me to go green, I will, but in the mean time much as I want to save the planet and everything I have bills to pay :-(
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SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
I have to admit, solar shutters make more sense.
This wouldn't be bad as a DIY project for a sun-facing wall that gets too much light, though. Or a porch, to power the porch lights (like a solar lantern, but bigger).
Obviously not the solution for everyone. I, for one, have a tree to the south, which would likely displease the new solar curtain overlords.
What would be a cool application for solar fabric is a canopy (say, for an outdoor market). That could provide shade while powering lights or electronics (like cash machines) in the stalls. Or self-lighting party tents.
One other thing -- how come I've never seen, anywhere, the idea of putting a hydroelectric turbine in a sewer line?
I once worked in a office full of civil engineers so perhaps I can answer that question, here goes...
There is one point that should be understand right off the bat and that is that any time a generator is introduced into a system where current, water, sewage, or energy flows freely a load is induced upon the system and the total energy outflow is reduced (i.e. the velocity of the outflow is slowed by the generator as the generator converts that energy into electricity or perhaps a water wheel is turned in which case some of the energy of the outflow is being converted directly into mechanical work). I realize that this is a very rough description of the physics, but would the thermodynamics geeks please cut me some slack? Thanks.
Now, the typical sewer lateral (the pipe from your home or building to the main in the street) has an average fall of 1/2 percent over the distance that it travels to the main or just enough to ensure that the raw sewage makes it all the way to the main without backing up in your lateral. It might be possible to introduce some sort of turbine in there but there several problems:
1) Raw sewage tends to be sludgy with lots of trash, hair, and other assorted junk that is just perfect for chocking or clogging your turbine (this might be less of a problem if you are only talking about the outflow from your home, but it is still an issue).
2) As previously mentioned there is barely enough fall to ensure that the sewage makes it all the way to the main without obstructions (and the turbine is an obstruction) so any back pressure will back up your sewage.
3) Digging a ditch for your lateral with greater average fall is possible but the main sewer line is only so much deeper than the street surface so practically speaking how much extra slope could you fit into the distance between your home and the street? Probably not enough to increase velocity substantially and thus not enough extra energy to convert to electricity with a turbine.
4) Greater slopes mean higher velocities and ultimately higher pressures and higher pressure pipes and turbines are always more expensive (just ask the guys who run oil and natural gas pipelines). In fact, they used to hydraulically mine gold in California using pressurized jets of water at lethal force from slopping troughs over long distances into ever narrower pipes fed from upstream rivers and streams.
To sum up: There is not enough useful energy to extract from your out flowing sewage over the distance from your home or building to the sewer line in the street to make the generator worth a crap (pun intended), it would probably just back up your sewage lateral and even if you had a very large property there probably isn't enough difference in slope between your toilet and the street to build up enough energy to make it worthwhile unless you have a very large property and your house is built on top of a hill our mountain. There is also the problem that toilet flushes are very sporadic in most residential situations so even more energy will be lost to spinning up the turbine on each flush as opposed to keeping a spinning turbine going. Basically, in most cases it just wouldn't be worth it.
As with seemingly everything, it's already been done.
Unisolar has been making these shingles for years. Maybe others are too now. I don't know much about them, just read about em online.
-Matt
2) I've replaced all the bulbs at both my parents' houses with compact florescents.
3) I've put smart strip outlets on my entertainment center in the living room, and the tv/dvd/roku box in the bedroom so everything is only on when the TV is on.
4) I've replaced desktops in the house with laptops (big energy saver there)
5) My favorite: I converted an old diesel generator to run on biodiesel/waste vegetable oil/etc. It's set to run in the morning about 30 minutes before I get up. It's coolant runs through a heat exchanger to preheat my water to about 100-120 degrees for the shower (in the event it's not running, a tankless hot water heater does the work). The power is fed back into my utility.
Some of us are trying the best we can =)