Skip to content
View in the app

A better way to browse. Learn more.

Power Forum - Renewable Energy Discussion

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

PV difference sunny/partly cloudy

Featured Replies

Hi the Forum.

Why is there such a difference  in maximum PV amps on sunny compared to partly cloudy days?

PV is N facing 3000W and on partly cloudy days I see maximum of 3100W/56A but on sunny days

maximum of 2300W/43A approximately. 

Is this normal?

Thanks

Rob 

 

2 minutes ago, RobG said:

Is this normal?

Yup. Two reasons.

1. Cooler temperatures. On days with lots of sun, everything tends to bake a bit warmer, and PV panels don't like to be hot. They make less power under those circumstances.

2. Cloud flare effect. As the sun shines through the edge of the cloud, it tends to flare and you get insolation spikes that are higher than the 1000W per square meter that PV panels are rated at, giving you a nice big spike.

3 minutes ago, RobG said:

Hi the Forum.

Why is there such a difference  in maximum PV amps on sunny compared to partly cloudy days?

PV is N facing 3000W and on partly cloudy days I see maximum of 3100W/56A but on sunny days

maximum of 2300W/43A approximately. 

Is this normal?

Thanks

Rob 

 

Yes it is. 

You have to consider cloud edge effect, which can add 20-40% extra radiation.

1 hour ago, plonkster said:

Yup. Two reasons.

1. Cooler temperatures. On days with lots of sun, everything tends to bake a bit warmer, and PV panels don't like to be hot. They make less power under those circumstances.

2. Cloud flare effect. As the sun shines through the edge of the cloud, it tends to flare and you get insolation spikes that are higher than the 1000W per square meter that PV panels are rated at, giving you a nice big spike.

I know some people like that as well ;)

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.