DIY Solar panels - a scam?

McSack

McSack

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I've come across a couple of products promising miracles wrt energy generation.
"Apparently" one can build cheap, efficient solar panels in the backyard shed that will provide you with 60-80% of electricity needs ... and if you really apply yourself, allow for that magical "off-grid" leap we all dream about

Generally I reckon if it sounds too good to be true, then it probably is ... but some part of me really wants to try this sht out.

Two I've looked at
Home Made Energy
Green DIY

Cost for the instruction manuals isn't too bad, but I wonder if the content isn't just a load of seriously complicated technical horse-sht. Also a bit pointless if necessary materials are not readily available in SA
 
You CANNOT build your own solar panels. Never mind meeting 60-80% of your electricity needs, they dont even know what your needs are...

Most Solar Installations, use solar heat to supplement the Geyser as its usually a major component of your energy bill. But photo-voltaics? I dont think you can get much out of them at this stage, unless if you have Huge resources (cash) and Vast open fields which are drenched in Solar radiation. Oh and batteries to store the energy are also kak.
 
Gona go with its a scam. With the amount of interest and investment in alternate energy.....any cheap option would have been very well known and published.
 
Just to give u an idea, i did a bit of research into this a while ago and it was something like R200 000+ to supply the needs for a house.
 
BrokenLink said:
Just to give u an idea, i did a bit of research into this a while ago and it was something like R200 000+ to supply the needs for a house.
Click to expand...

But maybe it's all a big conspiracy? lol They already have fusion reactors but they just don't want the price of oil to go down yet...
 
The best in bleeding-edge research panels (ones which are impractical to mass produce consequently) give you an efficiency of just under 50% (i.e. Less than half of the solar power coming in is converted to electrical power). If you mean build an array yourself, you can do it but you'll be looking at efficiencies of about 20-30%. You can then do some basic primary school maths to determine the area needed given (in some multiplicant of W/m^2) and requried power (W).
 
If you think you are going to be able to run your house from solar power... forget it! You will have an array bigger than your entire stand, and you will likely not be able to afford all the required panels.
 
It's possible. You can run part of the house on solar, cut your bill 1/2. But your initial layout is a lot!

1. Start with a Solar Geyser +-R25k+
2. Go Gas on stove / heating.
3. Solar panels + batteries + inverter : you should be able to run a few stuff from it, depending on the size of your battery bank.
Make sure your charging circuits don't discharge the battery's lower than 60%.
Switch the houses lights to 12v. More efficient, no need to inverter.

It's very possible to go off the grid, but it's not cheap.
I do agree, that kit sounds like a scam.
 
McSack said:
I've come across a couple of products promising miracles wrt energy generation.
"Apparently" one can build cheap, efficient solar panels in the backyard shed that will provide you with 60-80% of electricity needs ... and if you really apply yourself, allow for that magical "off-grid" leap we all dream about

Generally I reckon if it sounds too good to be true, then it probably is ... but some part of me really wants to try this sht out.

Two I've looked at
Home Made Energy
Green DIY

Cost for the instruction manuals isn't too bad, but I wonder if the content isn't just a load of seriously complicated technical horse-sht. Also a bit pointless if necessary materials are not readily available in SA
Click to expand...


Got some links we can inspect?

As above... you can go off-grid, but it will cost lots of dosh (if you want to generate electricity and not just use a solar geyser or heat up the pool), and it's no conspiracy theory. The electricity side of things can only really come in two forms (wind or photovoltaic solar panels - which themselves can either be crystaline or amorohous silicone, or thin film). All of the above will cost.

There's no garden shed solution for elec generation unless you go with wind and build your own generator.
 
spiderz said:
Switch the houses lights to 12v. More efficient, no need to inverter.
Click to expand...

Its better to stay with AC and using inverters, it has to do with the battery AmpHour rating,
for example:
Volt x Amp = Watt
so A = W/V
50W / 230V = 0.217A
or 50W / 12V = 4.166A
therefore a 50AmpHour battery will last longer inverting to AC than running things in DC.

If you still want to go 12V, you would have to re-wire the house with cables specific to 12V. Because of the higher Amps you need thicker cables. If you keep the existing cables and shove 4Amps down the line, things will get very hot very quickly, melting plastic, short circuits, and BIG POO POO!!!!!

Regards,
Monty.
 
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Monty, I don't think you are comparing it correctly.

50W / 230V = 0.217A on the AC side (output of the inverter) but still 4.166A DC from the battery is needed at the input. So it is the same as running off 12V directly.

In fact, running off 12V can be slightly better because you don't have conversion losses of around 10% between the battery and the inverter output.

But yes, you do need thicker wiring potentially.
 
PV panels use Gallium & stuff. No way you're building that at home.

Even in a standard lab setup it would be pushing it.
 
I read DIY Solar panel not DIY voltaic cells in the topic? Maybe its just me but building your own solar DIY panel with voltaic cell components may be viable if the components can be acquired cheaper to make a self build panel than purchasing a "market" panel. I have seen a web article where someone was getting broken solar pieces from a factory and build up a panel like a Jigsaw puzzle, lots of soldering. Yeah, so it's ugly for the Sun to look at but who cares if the panel just cost a fraction of the full price of a beautifully manufactured panel but still delivers the same voltage and current?

BTW Solar "water" heater panels also fits under the topic as it uses a panel to collect solar heat to warm water and save energy.
 
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MegasXLR said:
I read DIY Solar panel not DIY voltaic cells in the topic? Maybe its just me but building your own solar DIY panel with voltaic cell components
Click to expand...
The cell either works or it does not so essentially you'd be competing against a mass manufacturer on the assembly cost....no thanks.
 
MontyPython said:
Its better to stay with AC and using inverters, it has to do with the battery AmpHour rating,
for example:
Volt x Amp = Watt
so A = W/V
50W / 230V = 0.217A
or 50W / 12V = 4.166A
therefore a 50AmpHour battery will last longer inverting to AC than running things in DC.

If you still want to go 12V, you would have to re-wire the house with cables specific to 12V. Because of the higher Amps you need thicker cables. If you keep the existing cables and shove 4Amps down the line, things will get very hot very quickly, melting plastic, short circuits, and BIG POO POO!!!!!

Regards,
Monty.
Click to expand...

ROFLD!.

So why doesn't Eskom provide us with 1 V electricity to the home?
 
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