# About the Site Feedback category
**URL:** https://forum.cleanenergyreviews.info/t/about-the-site-feedback-category/2
**Category:** Site Feedback
**Created:** [September 11, 2018, 7:45am UTC](https://forum.cleanenergyreviews.info/t/about-the-site-feedback-category/2 "2018-09-11T07:45:02Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@system](https://forum.cleanenergyreviews.info/u/system)
#### Post date: [September 11, 2018, 7:45am UTC](https://forum.cleanenergyreviews.info/t/about-the-site-feedback-category/2/1 "2018-09-11T07:45:02Z")
Discussion about this site, its organisation, how it works, and how we can improve it.
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### Author:  [@jss](https://forum.cleanenergyreviews.info/u/jss)
#### Post date: [February 10, 2023, 4:58pm UTC](https://forum.cleanenergyreviews.info/t/about-the-site-feedback-category/2/2 "2023-02-10T16:58:42Z")
Your page about controllers, [MPPT Solar Charge Controllers Explained — Clean Energy Reviews](https://www.cleanenergyreviews.info/blog/mppt-solar-charge-controllers) has a section about Solar Panel Voltage vs Battery Voltage. Here is an excerpt:
… For an MPPT charge controller to work correctly, the solar panel operating voltage must be at least 4V to 5V higher than the battery charging (absorption) voltage, not the nominal battery voltage. **On average, the real-world panel operating voltage is around 3V lower than the optimum panel voltage (Vmp).**
I believe this is only true fur PWM controllers. For example, Renogy states that their MPPT controllers can raise the solar input voltage to the voltage needed for battery charging, so-called boost controllers.
I hope this helps,
jon stivers [acimasolar.com](http://acimasolar.com)