Anyone Seen Usefull Solar Panels Around?


Polossatik said:
* 9 to 12 volt (1 A max) solar panels who are using the best possible way (DC-DC converter is what i'm now looking at) to output 5V - this should be fairly compact from electronics but indeed maybe a bit more expensive.

Take a look at this DC-DC converter:
http://www.dimensionengineering.com/DE-SW050.htm

I have some of those regulators (including the adjustable one), which I plug in special cables I made for powering several devices with the same 9,6V NiMh battery as needed (audio recorder, photo camera, nds, guitar amp, more instruments...). Efficiency seems very good (83%-87%). And they send it worlwide for $1.25.
 
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Looks good, certainly for that price and way better then a 7805... but it needs 5v+ 1.3v to work as input...

I'm however trying to see if any converter with "step up" might be possible to use.

Still torturing google...
 
I was out doing some last minute chrimbo shopping (xmas eve, as ever) when I stumbled across the bargain of the century in TJ Hughes of all places.

Its a hand-crank mobile phone charger made by a UK company called UNI-COM. It features a surprisingly good 3x white LED torch (activated when not in charger mode) and even has a shoddy compass built in too! It has adapters for all popular hand sets inc. mini USB to juice our Pands.

£6! :eek:

Yep 600 pence! Barg!
 
danboid said:
I was out doing some last minute chrimbo shopping (xmas eve, as ever) when I stumbled across the bargain of the century in TJ Hughes of all places.

Its a hand-crank mobile phone charger made by a UK company called UNI-COM. It features a surprisingly good 3x white LED torch (activated when not in charger mode) and even has a shoddy compass built in too! It has adapters for all popular hand sets inc. mini USB to juice our Pands.

£6! :eek:

Yep 600 pence! Barg!
I'm deeply sorry but I have no intention to "crank up" my Pandora... I have an intention to actually do different things with my life the next 2 months after it's delivered...

By the way, what is it these day's with pseudo science? first Scientology came to Europe, then "intelligent design" and now poor old Tesla is the victim? I suggest that you actually verify a few of those rather silly claims made in your footer...But it's also possible you simply like Sarah Louise Heath Palin ... not sure which is worse...
 
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Polosic:

People like you really make me feel sick. I come and post in this thread to share info, trying to help people and all you can do is have a cheap crack at my expense. Absolutely pathetic! I realise the device I mentioned isn't a solar generator like you want but it is a cheap alternative energy source for the Pandora non-the-less.

What has Sarah Palin got to do with ANYTHING (apart from being from Alaska)? Do you really know anything about Tesla? Did you actually click on any of the links in my sig and do anything other than scoff and mock, you the superior being who always knows much better?

I know I'm probably wasting my time with you but I recommend you take a good look at

http://cheniere.org/

http://www.theorionproject.org/en/research.html

Lindsey Williams, who spent several years working for Big Oil, wrote a whole book on the Alaskan oil reserves btw and you can watch a presentation of his on Google Video

http://video.google.com/videoplay?docid=33...ergy+non-crisis

Or you can just carry on believing what the BBC, NBC, CBS, MSNBC, the Royal Society/Universities and the corporate media want you to believe, the choice is yours.
 
danboid said:
Polosic:

..etc etc..

Do you really know anything about Tesla? Did you actually click on any of the links in my sig and do anything other than scoff and mock, you the superior being who always knows much better?

etc..

Or you can just carry on believing what the BBC, NBC, CBS, MSNBC, the Royal Society/Universities and the corporate media want you to believe, the choice is yours.
I've seen those "evidences" you mention before, and contra to your statement they did not convince me at all. I've done extensive research on Tesla, both on and off line, so I'm pretty sure I have an idea who he was and what he did. I'm not superior, just tired of all this pseudo conspiracy, based on lose ends.
It's also quite arrogant from your side to assume because I disagree that I'm unaware of what you link.
so I think we are at least even, even if I find the usage of "Polosic" as a "joke" to my nick quite misplaced.

I humble apologies for going off topic, but your footer was just so misplaced in this context.
I don't use a footer *here* to share my "believes".

Peace.

Now back to Solar power.
 
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ledow said:
It just annoys me as a mathematician... you don't need to be a genius to do the mathematics but nobody bothers. It also annoys me as an amateur scientist - solar and wind are *STILL* a humungous waste of time on anything other than stupidly large scales where they *JUST* make energy "profit" for an enormous amount of effort.
Quoted For Truth, though I disagree with the spirit. Yes, anybody who can do basic math and can remember high school physics knows that solar chargers are completely impractical for a device like the Pandora. Perhaps if you spend long periods of time in sub-Saharan Africa or the Australian outback where sunshine is far more prevalent than reliable access to AC power, something like this makes sense. If you live in dreary old England, you're probably just kidding yourself.

But none of that is the point. The Pandora is a tinkerer's device. If these guys want to tinker, let them. Painting, reshaping and adding flashing lights to a Pandora requires time, money and energy with no practical return on investment, but plenty of people are going to do it anyway. Adding solar panels is a mod like any other, and people are welcome to mod however they wish.
 
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danboid said:
What has Sarah Palin got to do with ANYTHING (apart from being from Alaska)? Do you really know anything about Tesla? Did you actually click on any of the links in my sig and do anything other than scoff and mock, you the superior being who always knows much better?
One quick point:
If you've been paying attention to the 2008 US election, Sarah Palin believes (with you) that Alaska has enough oil to power the world for some amount of time. And let the useful discussion resume.
 
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ledow said:
It just annoys me as a mathematician... you don't need to be a genius to do the mathematics but nobody bothers. It also annoys me as an amateur scientist - solar and wind are *STILL* a humungous waste of time on anything other than stupidly large scales where they *JUST* make energy "profit" for an enormous amount of effort.

Yes, the *highly* efficient, top-of-the-range solar panels in good-sunshine spots can do lots of great things - power satellites (virtually 100%, but without any atmosphere in the way), power towns (with huge fields full of them and the associated maintenance costs) or power your house (if you can afford the £100,000 up-front cost and are prepared to take the chance that you'll not need to do many repairs over their operational lifetime).

However, 99% of suggested uses and places that sell such things don't realise that all they are doing is making the situation worse by producing some *horrible* chemicals, slapping them into a solar cell, selling them to joe-public, who thinks they are saving money when in fact over their operational life, they could have bought the equivalent in AA batteries or pulled off the grid and not incurred anywhere near 50% of the cost, unreliablity or production emissions (not to mention landfill).

The best example I've ever seen was in my local B&Q (DIY hardware store). A "fit-it-yourself-to-save-money" 2KW wind turbine that was bigger than my car. Aside from planning permission, fitting, connecting to your electrical setup, batteries, ongoing repair costs (ten-foot-wide blades don't take kindly to high winds or just general wear and tear), etc. the damn thing would never (not even at "theoretical maximum", assuming fixed/rising grid energy prices, etc.) recoup the initial outlay of just the device itself within its theoretical operational lifetime (five years, I think it said) if it operated 24 hours a day.

Solar - great for your calculator, but make sure you have a battery in it as well. My calculator has had a solar panel in it since the early 80's, we haven't progressed much since then. Give it another 5-10 years and either it'll work as advertised or it'll be replaced by something that does.
Air source heat pumps will probably replace the whole solar effort within 5 years, they really work and give 1kw in 5kw out efficiency at 6 degrees. I know because my house is heated by them :)
 
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craigix said:
Air source heat pumps will probably replace the whole solar effort within 5 years, they really work and give 1kw in 5kw out efficiency at 6 degrees. I know because my house is heated by them :)
heatpump2.jpg
:D
http://www.waynewhitecoop.com/pages/HeatPumps
 
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Using a booster circuit would be similar to my magnetic circuit suggestion(ok, without additional batteries needed).
Chip said:
If you live in dreary old England, you're probably just kidding yourself.
And that's the important thing to see. A LED Bonsai magnetic circuit addresses this problem best as possible(it surely can't eliminate the general inefficiency of photovoltaics). You could tune it to produce something utilisable in nearly every lighting situation except total darkness.

Btw. when I hear "Solar Charger" the first thing that comes to my mind is camping. If you just take such a simple charger out of your back pack and throw it on the floor somewhere, you will most certainly have some juice at night, to at least partly recharge Pandora while you sleep. No need to align the panel several times a day. The current delivered to the batteries in low light conditions is minimal but it is at least something, when you are somewhere without an outlet.

Heat pumps are very popular in Germany. About every third new building gets one, where I live. Very nice technology :)
 
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Ridiculously off topic, but as an HVAC tech, I have to comment on heat pumps.

Just so everybody is clear, heat pumps do not create electricity, they simply move heat via the standard refrigeration cycle (a process which consumes electricity) from inside to outside, or vice versa. It's hardly new tech - it was invented around the turn of the century and they've been installing them residentially since at least the 50s. They are relatively efficient and mechanically simple, but they become very inefficient for heating if the ambient temperature drops much below 20F. You see them a lot in condos and townhouses, especially in the south. Many office and residential towers use them as well with a building water loop, which can be cooled in an evaporative tower in the summer and heated with boilers in the winter. In a mild climate like England's, they make a lot of sense.

I just wanted to clarify that heat pumps are not really comparable to photovoltaic panels. One generates power while the other uses power to condition a space.
 
Here in Germany the mostly used versions are terrestrial heat collectors and groundwater fountain collectors to aquire the heat energy which is then transfered to a higher level by the heat pump needed for a underfloor heating system. The flow temperature of that system is very low, so it yields the highest efficiency. Air systems are rare, because they freeze over quickly and need a heating system for the outside module and operate at higher temperature levels, which both eat a lot of efficiency. The very interesting point of these systems is the fact, that they only need electricity to work and it's a fairly small amount of electricity. These systems are somewhat independent of fossile fuels, because if the energy-mix the electricity consists of shifts to more ecofriendly production like off shore wind generators for example, all of those heat pump systems automatically get more ecofriendly.
 
Yep, that is what I meant in terms of the future of clean tech, the power use on the new ones from Japan is so little you could consider going off grid, the UK has an almost perfect climate for them too. While mine are the Mitsubishi 1kw in 5kw out at 5-6degrees, there is already a 1 in 6 out one available in Japan, this technology is flying forward fast after being still for about 50 years.

That said I thought they had recently made some major advances with solar too?

If you don't have access to a gas supply solar panels can reduce your hot water heating costs quite well (I'd buy some second hand panels from ebay myself), although an air source water pump is a lot cheaper!
 
Those COP figures have to be taken with a grain of salt. I doubt, that they(air heat pumps) keep their efficiency at -15deg Celsius, there is much marketing talk going on ;) Well, it's seldomly that cold here anyway.

Solar collectors are generally more efficient than photovoltaics. They are very well suited to produce the whole warm sanitary water in summer(especially good for people who would instead heat that water with gas or oil otherwise).
 
Totally Offtopic here, but:
QUOTE
Yes, the *highly* efficient, top-of-the-range solar panels in good-sunshine spots can do lots of great things - power satellites (virtually 100%, but without any atmosphere in the way), power towns (with huge fields full of them and the associated maintenance costs) or power your house (if you can afford the £100,000 up-front cost and are prepared to take the chance that you'll not need to do many repairs over their operational lifetime).
My house is run purely on solar (with a generator as backup), its not mains connected at all. It cost about $23,000 AUD unsubsidised 15 years ago. This includes 10x Solar panels, 12x 2V Batteries, 2x 5m Towers and an Inverter. Due to government subsidies it cost my parents $8000 AUD, which was the same price as getting powerlines up to our house. So it made sense economically, as well as environmentally.

The only maintainance we've had to do is spend $5000 AUD to replace the batteries every ~10 years. However i wouldn't say its exactly equivalent to being mains connected. When the suns out your pretty unrestrained but you generally dont want to make heavy use of heaters/toasters/ovens at night or during winter.
 
I'm asking input from Mweston on this, still discussing this with him but he did provided already something that is good to know (I quote):

"the voltage should always be between 5 and 6 volts with 5.2-5.5 volts being the best. If the voltage goes above 6.5V-ish, the DC input will be shut off and the system will fall back to battery power"

(Edit: To avoid any mistakes this is about the 5v DC input jack, not the USB power)

This makes sense seen most "standard 5v powersupplies" are really not that well regulated, hence only dropping to 5v when on full load but easily go to 5.8v or so when only providing a light load.

So we should regulate to 5.3 V or so not 5.0 V.
It also means that some ripple on the regulation would not cause any problem as long as it is not to high ( a few 0.1 V's).
 
Great info! :)
This should be included in the Dev Team Updates list and the Community Blog.

Edit:
If someone wants to build and emergency battery pack for mobile charging, 5 NiMh cells plus one 7806 regulator(just in case, to prevent a shut-off of the circuit when using fully charged cells) would be the ideal solution to maximize the charging capability till the cells are empty. Of course a low voltage diconnect circuit should be included, too to prevent damage of the cells.
 
ledow said:
It just annoys me as a mathematician... you don't need to be a genius to do the mathematics but nobody bothers. It also annoys me as an amateur scientist - solar and wind are *STILL* a humungous waste of time on anything other than stupidly large scales where they *JUST* make energy "profit" for an enormous amount of effort.

Yes, the *highly* efficient, top-of-the-range solar panels in good-sunshine spots can do lots of great things - power satellites (virtually 100%, but without any atmosphere in the way), power towns (with huge fields full of them and the associated maintenance costs) or power your house (if you can afford the £100,000 up-front cost and are prepared to take the chance that you'll not need to do many repairs over their operational lifetime).

However, 99% of suggested uses and places that sell such things don't realise that all they are doing is making the situation worse by producing some *horrible* chemicals, slapping them into a solar cell, selling them to joe-public, who thinks they are saving money when in fact over their operational life, they could have bought the equivalent in AA batteries or pulled off the grid and not incurred anywhere near 50% of the cost, unreliablity or production emissions (not to mention landfill).

The best example I've ever seen was in my local B&Q (DIY hardware store). A "fit-it-yourself-to-save-money" 2KW wind turbine that was bigger than my car. Aside from planning permission, fitting, connecting to your electrical setup, batteries, ongoing repair costs (ten-foot-wide blades don't take kindly to high winds or just general wear and tear), etc. the damn thing would never (not even at "theoretical maximum", assuming fixed/rising grid energy prices, etc.) recoup the initial outlay of just the device itself within its theoretical operational lifetime (five years, I think it said) if it operated 24 hours a day.

Solar - great for your calculator, but make sure you have a battery in it as well. My calculator has had a solar panel in it since the early 80's, we haven't progressed much since then. Give it another 5-10 years and either it'll work as advertised or it'll be replaced by something that does.
Solar power is great if it is used properly. Photovoltaics (PV) aren't very practical in most situations. Solar heat and solar electricity generated by solar heat is very good. As I pointed out earlier, PV is good in southern latitudes, especially CA due to their tiered rate structure. In this scenario, the cost of electricity goes up as use increases. So you could buy a small system that takes you out of the 2 top tiers and save a lot of money, especially with tax incentives. The energy recoup times is usually only a couple of years and the cost recoup time is about 7 years (at the top tier rates).
Solar hot water is feasible in most of the US as is solar heat, especially when designing a new house. You can implement passive and active solar heat + add solar hot water. In the lower latitudes people could get boiling water from their solar hot water. Mixing solar heat and solar hot water with geothermal and passive solar in new home construction will save quite a bit of energy and will quickly pay for itself.
Installing commercial generation stations in the south, especially the desert American southwest is a great idea and is being done. They are just the beginning and as low heat electric generation matures you will see it become more and more efficient.
There are also projects being done to use fiber optics to light buildings during the day with solar. Solar concentrators reflect sunlight (minus the IR band) onto collectors which route the sunlight into office building and department stores. The natural light looks better and works with peoples bio-rhythms much better. The light is soft in the morning and quitting time and harsher during the rest of the day. Workers are shown to be more productive and store displays look better under this natural light than artificial. It also works on a blend, so on cloudy days the building isn't effected (it just uses more artificial light).
Wind has major problems due to the intermittent nature of wind and with the fact that the winter is more windy than the summer which is when electricity use goes way up from air conditioning. I have heard that every megawatt of wind energy put on line has to be met with a megawatt of conventional generation. There is a project being designed right now that will put a wind farm off the coast of Maine that has 100% wind during the winter and since there is so much electric heat up there, all of New England's heating can be met with this farm. It's supposedly the windiest spot on earth during the winter. We will see what happens.

My big hopes are on Algae and other bio-mass and that PV will improve as more and more people buy it and give the companies R&D money. Hydrogen is a dead end. and their needs to be replacement liquid fuels. Even if we got radiation free fusion and could generate more than we need, hydrogen (which is made from electrolysis) is still too dangerous. Electric cars have too many problems and are unlikely to be resolved in the foreseeable future. Imagine the nightmare of batteries. There is no existing battery technology that is ready for electric cars and a replacement liquid fuel is needed. Switchgrass and Algae (especially Algae) are very good for replacement liquid fuels. Algae can produce Airplane fuel (Kerosene), Diesel and Gasoline and can be "farmed" anywhere, not just on our valuable farm land. It can also be done with salt water. Imagine an algae farm in the desert using salt water irrigated in from the ocean. It also grows very fast and doesn't have a once a year crop. More like every couple of days which is constant supply.

Besides renewables, there isn't any new energy sources on the horizon (except maybe fusion) and we are going to have to diversify since no one solution can replace ff. If we want to keep our modern society, replacements to FF needs to be found and since we don't know any other magic bullet that oil was/is, renewables and lots of them will have to be made to work.

Polossatik said:
Charging a battery seams to have about 75% efficiency (or worse) when charging, aka to fully charge an 7.5 watt battery you need at least 10watt "input".
So if you first charge a battery to use that later to charge a other device then you lose already at least 75% in the "inbetween" battery, then pumping energy into something like a pandora looses another 25% at least... not counting losses in voltage convertors etc
Charging a battery is very efficient (approaching 100%) when the battery is near dead and remains so until about 70% charged and then the efficiency drops like a stone, giving an AVERAGE 75% or so efficiency (ni-ad and NIMH. I'm not sure about Li-ion). IF you charge your batteries to only 70% or so, the efficiency is great. There is a book on the internet called batteries for dummies or something like that and it's great for understanding batteries, maintenance etc. You may want to check it out.

Chris
 
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