PermalinkSubmitted by Ryousuke Ishikawa on Tue, 02/27/2018 - 02:14

Nice to meet you. I am grateful to have studied with your wonderful teaching materials.
Recently sliders and Flash animations on the web do not seem to work well.
I tried the latest FlashPlayer with Chrome, IE and Firefox but it did not work.
What should I do?

PermalinkSubmitted by ganley0905 on Tue, 07/24/2018 - 10:32

This is a question, not a comment. Can I copy figures from one of your pages for use on a website I am building for my startup? I will acknowledge your site as the source. Thanks. J. T. Ganley

PermalinkSubmitted by TimCHEN on Wed, 12/30/2020 - 03:42

This website supplies abundant, detailed, and reliable resources for PV learning! I've studied some parts of the section "properties of sunlight". It helps me a lot in deed. Thanks!

PermalinkSubmitted by holretz on Wed, 03/02/2022 - 17:15

I live in Aasiaat, latitude 68,7 degrees north. According to the curves for calculation of solar incidence, a solararray should be tilted around 55,5 degrees. It says somewhere else on one of the pages, that one should choose tilt equal to latitude.
This is clearly not the case for my latitude, so I don't quite understand this statement....is it true for some limited range of latitudes ?

PermalinkSubmitted by Peter W on Wed, 10/26/2022 - 07:20

I believe the formula given for solar radiation on a panel with arbitrary orientation and tilt is incorrect. I think it should be:
Smodule = Sincident .cos(Ψ-θ).[cos(α)sin(β) + sin(α)Cos(β)]

Reason: On the previous page, for a module directly facing the sun, at tilt β:
Smodule = Sincident. sin(α+ β), where
sin(α+ β) = cos(α)sin(β) + sin(α)Cos(β)
For a module at orientation θ,
Smodule = Sincident .cos(Ψ-θ). sin(α+ β), so
Smodule = Sincident .cos(Ψ-θ).[cos(α)sin(β) + sin(α)Cos(β)], not as given.

PermalinkSubmitted by petercl14 on Thu, 05/02/2024 - 03:36

Hi, Equations for the position of the sun,. elevation angle and azimuth. If I enter 9 for 9am in the morning being the local time in the equations I get accurate results. I compare the result with an application on the internet which gives the elevation and azimuth at my location and time. However, if I enter say the number 13 for 1pm I no longer get an accurate or comparable result.
Can you please let me know what I should enter in the equations for pm times? Should this be perhaps a negative number? I never had to put 'am' after the 9 in the equation.
I am making a computer application using the equations to simply put in the local time and days since the start of the year to give me the elevation and azimuth of the sun. These are the only variables in the equations. All the other data is fixed for my location. The application on the internet also probably uses these equations.
Please let me know the local times I should enter for the pm time to get an accurate result. Thanks.

## Comments

## how I can save this CD

how I can save this CD

## There is no off line version

There is no off line version at present.

## HI

HOW CAN I FIND THIS INFORMATION ON BOOKS PDF

## hard copy

hello sir, im electrical engineer.I need a hard copy of whole attachments.

waiting for your kind responce.

thank you.

## iPhone,iPad..

How to see the animations on iPhone and iPad ...

## The animations are in flash

The animations are in flash that is not supported by the iPad. Unfortunately there are still no suitable substitutes.

## Flash animations

Nice to meet you. I am grateful to have studied with your wonderful teaching materials.

Recently sliders and Flash animations on the web do not seem to work well.

I tried the latest FlashPlayer with Chrome, IE and Firefox but it did not work.

What should I do?

## As far as I know they still

As far as I know they still work. Which page is the problem?

## USe of Figures from your site

This is a question, not a comment. Can I copy figures from one of your pages for use on a website I am building for my startup? I will acknowledge your site as the source. Thanks. J. T. Ganley

## As long as you acknowledge

As long as you acknowledge the source of the images you may use figures for your site. If it is a website just make sure you have at a minimum

Picture: www.pveducation.org

And a link to the website.

## Printing Sections

I'd love to be able to print sections instead of part by part.

## User's feeling: Powerful and practical website for photovoltaics

This website supplies abundant, detailed, and reliable resources for PV learning! I've studied some parts of the section "properties of sunlight". It helps me a lot in deed. Thanks!

## module tilt in Aasiaat

I live in Aasiaat, latitude 68,7 degrees north. According to the curves for calculation of solar incidence, a solararray should be tilted around 55,5 degrees. It says somewhere else on one of the pages, that one should choose tilt equal to latitude.

This is clearly not the case for my latitude, so I don't quite understand this statement....is it true for some limited range of latitudes ?

## S 2.4 Arbitrary Orientation and Tilt

I believe the formula given for solar radiation on a panel with arbitrary orientation and tilt is incorrect. I think it should be:

Smodule = Sincident .cos(Ψ-θ).[cos(α)sin(β) + sin(α)Cos(β)]

Reason: On the previous page, for a module directly facing the sun, at tilt β:

Smodule = Sincident. sin(α+ β), where

sin(α+ β) = cos(α)sin(β) + sin(α)Cos(β)

For a module at orientation θ,

Smodule = Sincident .cos(Ψ-θ). sin(α+ β), so

Smodule = Sincident .cos(Ψ-θ).[cos(α)sin(β) + sin(α)Cos(β)], not as given.

## entering local time in equations of sun

Hi, Equations for the position of the sun,. elevation angle and azimuth. If I enter 9 for 9am in the morning being the local time in the equations I get accurate results. I compare the result with an application on the internet which gives the elevation and azimuth at my location and time. However, if I enter say the number 13 for 1pm I no longer get an accurate or comparable result.

Can you please let me know what I should enter in the equations for pm times? Should this be perhaps a negative number? I never had to put 'am' after the 9 in the equation.

I am making a computer application using the equations to simply put in the local time and days since the start of the year to give me the elevation and azimuth of the sun. These are the only variables in the equations. All the other data is fixed for my location. The application on the internet also probably uses these equations.

Please let me know the local times I should enter for the pm time to get an accurate result. Thanks.