peak hours

I have to say about this is very interesting, it seems that many people like it.Okay, I will recommend my friends to have a look, look forward to the new content.

Mod note - forget the links

[miike012]

yeah I woud like to buy a few cells put them together and experiment on how to get more sun light, I was thinking of playing with lenses and things like that. I only want the system to be like 10 W so obviously something small at first.

[russ]

Are there any free online books or pdf's to teach me how to put a pv cell together? I only want to play with a small 40 watt panel.

Put a PV cell together? You mean a 3 x 6 cell - read posts on the forum - ain't no easy way

[miike012]

no books?

[Ian S]

the system that I have been looking at for my project is around 37000 dollars that includes installation and the 25 327 watt sunpower panels. After calculating the possible incentives the total cost is around 22000 dollars. My friend was doing some calculations and he is saying that we will never save any money. Can someone direct me to a site with incenctives for arizona? Im hopeing if I can save more money we will actually be able to save money.

The incentives for Arizona are the 30% federal tax credit, a $1000 state tax credit and the utility rebate which varies depending on the utility. Assuming your calculation is for APS, it sounds about right. That size system in Phoenix with no shading issues should be capable of saving you around $1600/year based on today's APS pricing. It will eventually pay off but not for quite a few years.

[miike012]

Are there any free online books or pdf's to teach me how to put a pv cell together? I only want to play with a small 40 watt panel.

[andrewc]

Also, consider moving to Louisiana :P

[russ]

the system that I have been looking at for my project is around 37000 dollars that includes installation and the 25 327 watt sunpower panels. After calculating the possible incentives the total cost is around 22000 dollars. My friend was doing some calculations and he is saying that we will never save any money. Can someone direct me to a site with incenctives for arizona? Im hopeing if I can save more money we will actually be able to save money.

On the forum page - on the right side you will see a link titled 'federal & state incentves - same link as follows

http://www.dsireusa.org/

Then you click on Arizona

[miike012]

the system that I have been looking at for my project is around 37000 dollars that includes installation and the 25 327 watt sunpower panels. After calculating the possible incentives the total cost is around 22000 dollars. My friend was doing some calculations and he is saying that we will never save any money. Can someone direct me to a site with incenctives for arizona? Im hopeing if I can save more money we will actually be able to save money.

[andrewc]

My questions is, how is the power of the module determined?

Same way power is normally determined, Ohm's Law. Power is equal to amperage times voltage. The amperage of a solar cell is proportional to irradiance (exposure to the sun), and voltage is inversely proportional to temperature. The power output of a module changes constantly throughout the day as those conditions change. Angle of sun and cloud cover change irradiance, and the temperature goes up and down. However, there are a number of standard test conditions where manufactures can say their panel will produce X under certain specific conditions. This is what STC and SOC and PTC are, various conditions whose parameters determine the power output of a panel.

PTC is 3rd party test results under real application.

I think this should be qualified that PVUSA isn't physically testing every single panel themselves, but instead are applying a statistical model to the given parameters of a panel. Their parameters are intended to be more of a real world application than STC, but isn't actually a result of a real test. It's just maths. Some panel manufactures flash test their panels upon shipment, and include that data with the shipment, so you could have specific data for each individual panel, but perhaps that is getting a bit off topic.

[Naptown]

STC is strictly a lab measurement under very strict controlled conditions. PTC is 3rd party test results under real application.

PTC and/or/ ratings are used to qualify for state/federal/local incentives and SREC.

This is also what PVwatts, Pathfinder and Solmetric Eye use to determine the annual output.

[Naptown]

I have a question about power of the module. Under STC my module says it is 333 watts but under PTC it says 247 Watts. My questions is, how is the power of the module determined?

thank you.

If that is the case yo got ripped off.
I will reject any module that PTC is less than 87% of STC without question.
that module is 74% of STC
Can you get your money back?
Most quality modules are in the 88-90+% range of PTC to STC

[Sunking]

I have a question about power of the module. Under STC my module says it is 333 watts but under PTC it says 247 Watts. My questions is, how is the power of the module determined?

thank you.

STC is strictly a lab measurement under very strict controlled conditions. PTC is 3rd party test results under real application.

PTC and/or/ ratings are used to qualify for state/federal/local incentives and SREC.

[miike012]

I have a question about power of the module. Under STC my module says it is 333 watts but under PTC it says 247 Watts. My questions is, how is the power of the module determined?

thank you.

[Naptown]

If you want high efficiency Suntech are not top of the line eficiency wise.
Look at Sanyo and Sunpower