Just a quick question about glass

[inetdog]

I want to say capacitor, but that's not right.

Also, I'd love to know where you got the horrible fright nickname for Harbor Freight.

I would say capacitor too. It would be driven by the flyback transformer, and the CRT (picture tube) itself will act like a large capacitor with very good (glass) dielectric. To hold a charge that long the air would have to be bone dry and clean. Hours or even days or weeks is common enough. Years, on the other hand, I have not heard anyone describe.

The name Horrible Fright came into being back in pre-history, based on the value and reliability of what they sell. The first form to show up was just Harbor Fright.
There are similar mocking names for Home Depot (also called Big Orange), Lowe's (also called Blue), The U.S Snail Service, etc.

One of my favorite HF stories is their 3-ton jack stands, which are stamped 3-tons on each one and are actually rated for 3-tons of supported weight per pair!
After all, you only use them in pairs, right?

[tjames]

Some awfully impressive videos out there vacuum bagging the EVA / cell / glass sandwich, then heating in a simple 215F oven. Tedlar on the back. I'm not thinking they will leak when done properly. Call me a skeptic but I'm not seeing all commercial panels being made in such clean room environments as being described here.

A 3x5 panel has $60 worth of (6x6) cells, $10 of EVA, a simple frame and a sheet of glass. Looking at the glass is what led me to this thread. Could reasonable glass cost more than $2 a square foot? I suppose if you bought by the little piece on ebay, but glass ordered and bought properly I suspect can be found "reasonably."

Then I'd maybe consider the M215 Enphase micro inverters. Another $130.

So depending on glass I'm looking at ~$260 a panel, including the M215. Some will claim it will leak. Some will claim if there is the slightest hint of any moisture you're screwed, Some will claim some thermo-expansion differential will shatter things. I suppose all of thse things are possible on a poorly made panel. Looking at EVA working parameters, and a simple silicone vacuum bag, there's just no reason why a thought out oven wouldn't work. Glass / EVA / Cells / EVA / Tedlar http://www.thebackshed.com/windmill/...olarPanels.asp This guy did it. Many other have also.

Photofanatic- Send me a PM if you like and we can compare notes

[SunEagle]

Some awfully impressive videos out there vacuum bagging the EVA / cell / glass sandwich, then heating in a simple 215F oven. Tedlar on the back. I'm not thinking they will leak when done properly. Call me a skeptic but I'm not seeing all commercial panels being made in such clean room environments as being described here.

A 3x5 panel has $60 worth of (6x6) cells, $10 of EVA, a simple frame and a sheet of glass. Looking at the glass is what led me to this thread. Could reasonable glass cost more than $2 a square foot? I suppose if you bought by the little piece on ebay, but glass ordered and bought properly I suspect can be found "reasonably."

Then I'd maybe consider the M215 Enphase micro inverters. Another $130.

So depending on glass I'm looking at ~$260 a panel, including the M215. Some will claim it will leak. Some will claim if there is the slightest hint of any moisture you're screwed, Some will claim some thermo-expansion differential will shatter things. I suppose all of thse things are possible on a poorly made panel. Looking at EVA working parameters, and a simple silicone vacuum bag, there's just no reason why a thought out oven wouldn't work. Glass / EVA / Cells / EVA / Tedlar http://www.thebackshed.com/windmill/...olarPanels.asp This guy did it. Many other have also.

Photofanatic- Send me a PM if you like and we can compare notes

It is still not worth my time to take a chance to build my own panel and save a few bucks as long as commercially made panels are between $1 - $2 per watt. Maybe if that price goes back up to $5/watt a DIY will be worth the chance but not until then.

[tjames]

That's cool. But others like me are still interested in the numbers.

250 watt panels run $350 with no inverter? http://www.amazon.com/dp/B00635Y1AQ/...?tag=dradis-20

Why can't I build that same panel and knock off half that panel cost? Having built many exotic projects over the years, the panels seem straightforward.

[SunEagle]

That's cool. But others like me are still interested in the numbers.

250 watt panels run $350 with no inverter? http://www.amazon.com/dp/B00635Y1AQ/...?tag=dradis-20

Why can't I build that same panel and knock off half that panel cost? Having built many exotic projects over the years, the panels seem straightforward.

If you have the time and patience to DIY then enjoy. Hope it works out for you.

[tjames]

Thanks- I'm not finding a reason not to give this a whirl. I like the idea that I could make a batch, laminate them, then gang them into my expanding field of panels.

[green]

A lot of people look at...well... everything as an "investment". They always look towards "will it be worth it?" Well the money I spend on cells and materials comes out of my hobby budget. I don't look to make a return on my hobby money. Some people golf, others have classic cars, my point is that some people do this as a hobby and shouldn't be told it's not worth it.

[SunEagle]

A lot of people look at...well... everything as an "investment". They always look towards "will it be worth it?" Well the money I spend on cells and materials comes out of my hobby budget. I don't look to make a return on my hobby money. Some people golf, others have classic cars, my point is that some people do this as a hobby and shouldn't be told it's not worth it.

I agree. Anyone that takes the time and effort to perform a DIY on a solar panel should be in it for the fun and learning process.

I just try to caution people that what they build may not last long (if at all) as well as inform them that they shouldn't believe that they are necessarily saving money when you compare a factory made panel to their DIY panel at today's prices.

If the money and potential failures don't bother them, then I support their decision to explore and try out new things and hope the best for them.

[tjames]

I appreciate the responses, but why are these topics always trivialized? Just curious. A guy wants to look at panel-making and he's quickly labelled a hobbyist, here for the science project or to learn. If there's $100 a panel savings to be had, doesn't that deserve a look?

I haven't taken an inventory of all the panel makers, but I tend to think they don't assemble these in NASA clean rooms with zero humidity.

Are we quite sure that the $60 worth of solar cells can't be sealed on quality glass for significantly less than a panel maker charges? It's so labor-intensive, that if you extract out the labor by doing it yourself it would seem a significant savings is accessible.

Having reviewed this panel process, I'm not at all convinced that a high quality weather-tight panel can't be made for a lot less.

[SunEagle]

I appreciate the responses, but why are these topics always trivialized? Just curious. A guy wants to look at panel-making and he's quickly labelled a hobbyist, here for the science project or to learn. If there's $100 a panel savings to be had, doesn't that deserve a look?

I haven't taken an inventory of all the panel makers, but I tend to think they don't assemble these in NASA clean rooms with zero humidity.

Are we quite sure that the $60 worth of solar cells can't be sealed on quality glass for significantly less than a panel maker charges? It's so labor-intensive, that if you extract out the labor by doing it yourself it would seem a significant savings is accessible.

Having reviewed this panel process, I'm not at all convinced that a high quality weather-tight panel can't be made for a lot less.

I don't disagree that you have the ability to make a quality DIY panel that will last as long as a manufactured panel for less money. What I believe is that most people can't make a quality DIY panel or multiple panels that have the same specification in their "shop". There will be wide variations in the panel's output and quality. There will also be complete failures which in the end will cost more per watt than a group of manufactured panels.

So for a small or hobby sized system you have a great chance of saving money with DIY.

For a larger system, the odds that all the panels perform the same or last long goes down.

For a grid tie system, forget about using a DIY. They will never be approved by the local Utility.

That's my story and I'm sticking to it.

[tjames]

I just spent a lot of time on the phone with Consumers Energy, the utility provider here in Michigan. The Net Metering program does not care the source of the energy creation. I could have banks of squirrels riding bicycles generating DC current. They (Consumers Energy) do not care.

The interconnection equipment that connects distributed resources (squirrels) to an electric power system (Grid) must meet the requirements specified in IEEE Standard 1547. It's the interconnection equipment that must be IEEE 1547 approved, not the squirrels.

To be sure, I spoke with the engineer responsible for IEEE 1547. He kindly confirmed that I can use squirrels.

So I can Grid-Tie my homemade DIY solar panel that I make from individual cells.

[SunEagle]

I just spent a lot of time on the phone with Consumers Energy, the utility provider here in Michigan. The Net Metering program does not care the source of the energy creation. I could have banks of squirrels riding bicycles generating DC current. They (Consumers Energy) do not care.

The interconnection equipment that connects distributed resources (squirrels) to an electric power system (Grid) must meet the requirements specified in IEEE Standard 1547. It's the interconnection equipment that must be IEEE 1547 approved, not the squirrels.

To be sure, I spoke with the engineer responsible for IEEE 1547. He kindly confirmed that I can use squirrels.

So I can Grid-Tie my homemade DIY solar panel that I make from individual cells.

I do not necessarily believe that is true. Those squirrels would be required to have a UL listing for the electrical "system" as well as need to meet NEC to get approval. But then again maybe there are Utilities in Michigan that don't care what is connected to the grid.

Have you checked your insurance policy to see if your home will be covered should a fire break out at one of the connections of your homemade panels?

Look. I am not trying to persuade you to not go with DIY. I am trying to make sure you do not get yourself in a jam. Please be careful when it comes to electricity. It is not forgiving if mistreated.

[tjames]

I spoke to the IEEE 1547 engineer. They wrote the standard that utility companies like yours uses. The DC side does not have to be UL rated. UL is a for (big)-profit testing facility. A lot of folks think UL is a USA govt testing facility. They are pirates, nothing more.

Sorry, but feel free to contact them and confirm.

Maybe there's some other specific standard that comes into play here that I am as of yet unaware.

[SunEagle]

I spoke to the IEEE 1547 engineer. They wrote the standard that utility companies like yours uses. The DC side does not have to be UL rated. UL is a for (big)-profit testing facility. A lot of folks think UL is a USA govt testing facility. They are pirates, nothing more.

Sorry, but feel free to contact them and confirm.

Maybe there's some other specific standard that comes into play here that I am as of yet unaware.

All I can tell you is that before the Utility will allow a system to be connected to the grid it has to inspected. That is the "entire" system not just the inverter that is at the final connection. If the inspector passes the system then you are ok.

Just be aware that most electrical inspectors will not pass a system if there are components in it that are not UL listed or if anywhere in the installation the wiring and grounding does not meet the National Electric Code.

You can read all about the NEC concerning Solar PV systems. It is in Article 690.

[tjames]

That was very helpful! I read through the NEC guidelines, Article 690. Nowhere does it specify any testing standard or UL rating for the panels. Not that I could see. The closest reference to anything they want on the panel itself is:

Photovoltaic Module Module Marking
• NEC 690.51
• Modules shall be marked with Identification of terminal/lead polarity, maximum OCPD rating, and:
1. Open-circuit voltage (VOC)
2. Operating voltage (VMP)
3. Maximum permissible system voltage
4. Operating current (IMP)
5. Short-circuit current (ISC)
6. Maximum power

If there's something I'm missing, I'd be grateful for some clarification.