Reduce 36V solar panel output to 12V

Thread Starter


Joined Jan 5, 2005
I have a solar panel that has a 36V output. I'd like to be able to reduce it to 12V so it can be fed into a charge controller connected to a 12V deep cycle battery. Is that feasible, and at reasonable cost. I've attached the specs for the panel.

I see buck converters on Amazon for $20-$30 but there are always a few negative reviews where the item didn't work for long, or in one instance started a fire. I'd like to avoid both of those.

Here's an example:




SD Labs

Joined Dec 1, 2020

Input: Solar PV
Output: Charge Controller
Problem: You are having some readymade buck converter, but reviews are bad.

Here you will need a buck or buck-boost converter to perform Maximum Power Point Tracking (MPPT) along with voltage reduction.
Note: I suggested a buck-boost converter as the buck converter is not applicable for the entire voltage range of PV.
As the market is not according to your tailormade problems, you need to design your own buck converter.

Buck Converter:
It is a simple DC-DC converter that results in a lower output voltage as compared to the input voltage. Following is the structure of a conventional buck converter.


Design of Buck Converter:

One can design the buck converter according to the following equations.


Note: Here 'D' is the duty ratio. In order to generate the duty ratio, the MPPT algorithm to be written, otherwise the circuit may malfunction and you will not be able to get proper output voltage.

With Sincere Regards,
SD Labs

Thread Starter


Joined Jan 5, 2005
Thanks for both replies. :)
I didn't realize there were charge controllers that allow for different input and output voltages. Since I'll need to buy a charge controller regardless, I might as well get a device that performs both tasks. Thanks again.