peak hours

[miike012]

Also you have to realize the way Im going to go about my speach, I am a new customer.. I have never purchased solar in my life and no nothing about solar so I will be looking at and comparing data sheets (just like any other customer I would imagine) .

[miike012]

Sorry I need to know what about correct temperature?

I'm finding it very hard to search for information on cells, I think it because I'm trying to do all this reasearch in a short amount of time which is making me rush.

Anyways this is the outline of what I will talk about during my speach

1. Efficiency of cell

I was going to compare the density, efficiency, Pmax, Ptolerance, cell type of a list of moduals.. (I will get this info from the data sheet- Is this useless info when comparing a modual?) Anyways I will finally lead into why I picked the sun tech solar cell explaining that I believe it is most efficient which I need due to limited roof space... To be honest I dont have much time so i will probably be doing a little bs'sing...

2nd I will compare prices of a few systems and the first annual savings-( i will get this info by calling the dealer)

3rd talk about where and why we decided to mount the pv system where we did, my parner and I did a project to decided this which we will talk about in our speach

I will also talk about suntech warranty and why thats important/ how much I save using suntech/ and incentives.. I will throw this in there somewhere
I know this isn't a perfect outline but this is what I have in a limited amount of time, what do you think?

[russ]

That information you already have. Look at the document I provided a link to in post no.25

Info and stats is a meaningless statement. You need only to how to temperature correct for a particular panel in question.

For an individual cell or a DIY panel one might spend a million bucks on equipment and still have a half assed idea.

[miike012]

where can i find info and stats on the affects of high temp. on solar panels?

[russ]

I used a consistent 1000 w/m^2 because that is what the module was tested at.

1000 watts/m2 is part of the STC (Standard Test Conditions) - by using STC or PTC any lab with the correct equipment can verify the panel production.

A typical June day at my location

0600 1 watt/m2
0700 25 watts/m2
0800 58 watts/m2
0900 151
1000 404
1100 711
1200 831
1300 906
1400 920
1500 879
1600 787
1700 650
1800 445
1900 275
2000 113
2100 11
2200 0
total 7,167 kW/m2/day

PTC conditions are much more real world - 800 watts/m2

[miike012]

I used a consistent 1000 w/m^2 because that is what the module was tested at.

[russ]

is is 1.72 kwh/(m^2-day) energy produced good, bad, or average?

Considering it is based on an imaginary consistent 1000 watts/m2 insolation it is meaningless.

1000 watts/m2 is not the most insolation a panel can accept - I do not know where that misconception comes from.

The annual average insolation for Phoenix is 5.35 watts/m2/day - on a fixed mount you may achieve 85% of that

[miike012]

Does anyone know the rate at which srp raises the dollar amount per kwh? I can't find this info online...

[miike012]

is is 1.72 kwh/(m^2-day) energy produced good, bad, or average?

[inetdog]

"and does 1m2 mean 1 meter^2? What else might it possibly mean - one never uses the ^ sign that I have seen"

The use of "^" for exponentiation when you can't do superscripts is pretty common among science and particularly computer science types. I don't see it in specs or used by engineers much. The other common usage among that group would be meter**2.

[russ]

Comments within the text

[QUOTE=miike012;48133]

1) If your panel is 1m2 and all else is at 'normal'

what do you mean by normal? temperature, humidity, air clarity for a start

and does 1m2 mean 1 meter^2? What else might it possibly mean - one never uses the ^ sign that I have seen

[miike012]

[QUOTE=russ;48132]1) If your panel is 1m2 and all else is at 'normal'

what do you mean by normal? and does 1m2 mean 1 meter^2?

[russ]

1) If your panel is 1m2 and all else is at 'normal'

2) For temp coefficient try this link http://homepower.com/files/PVModuleB...pecDetails.pdf

[miike012]

Are my calculations correct? I want to calculate max energy of a single cell in one day.

Assuming there is 6 haours of peak sun ( I live in Arizona)

1. p(1000 w/m^2)*(20%) = 200w/m^2

I chose the value 1000 w/m^2 because this is the most power any panel can intake and I multiplies it by 20% because that is the efficiency of my panel.

From line 1. 200w/m^2*6 hours = 1.2 kwh in a day.

Is this correct?

[websterize]

I learned a lot about temperature coefficients from this "PV Math" piece by John Wiles:

http://www.nmsu.edu/~tdi/Photovoltaics/Codes-Stds/PV%20MATH.pdf