Solar Panel Half Cell Discussion

CA Traveler wrote:
Half Cell or Half Panels are ramping up production and I wanted to know how they work and are they suitable for a RV. I'm not an expert but this is what I found. Lots of sites have the basic half cell marketing information, more power, better shade tolerance, higher cost, pros and cons, etc. I found the link below that has excellent information and comparison of full cell and half cell panels and is the basis for this post using 72 full cell and 144 half cell panels.

https://www.youtube.com/watch?v=AZ8VQ_zmf1M&t=34s
This link also contains excellent graphics on how full cell panels operate in the shade with bypass diodes.

Based on my understanding of the above link the Half Cell panels require a new MPPT controller that can detect 2 power points - The Global Power Point and the Local Power Point and is based on the 5A half cell amp rating and the higher voltage associated with twice the number of cells in the panel and the unique cell layout. Increased shade power is dependent on the type of shade and the panel orientation to the shade. Shade may also reduce the power available for series panels as shown at time 8:30 to 10:00 in the link. 10:15 strongly suggests that heavy uniform shading like a solar farm is needed for half cut cell performance improvement. ie All modules need to be similarly shaded in the lower half on any given row (series string).

My take is that half cell series panels (with the new MPPT controller) are more likely to be a disadvantage for the typical RV due to the unique shade and shade orientation required for more shade power vs the full cell panels. Plus no doubt the new MPPT with additional power point cost.

What's your take on the video?

This is nothing new, I have been using a 24V 325W 120 split cell (or half-cell depending on the company) panel for three years now on my camper. Yes, they are more efficient and do much better in low light and shade. to give you an example of the improvements in efficiency I got, my 5th wheel has a 12V 480W solar set up run off a PWM controller and the best ever see is 21 Amps of charging, where as my MPPT with the 325watt split cell set up routinely gives me 22 to 23 amps in the middle of the afternoon. I also get more charging power in the early morning and lait at night. in the 5th wheel it's not uncommon for me to have to wait till 8:30 to 9 am before charging registers, the camper with the split cell will be putting out 0.2 amps at 6am and you can watch it rise as it gets brighter out. shading I can't speak on with technical data as I don't measure the panels as I observe the shadows, but I take the camper to mostly partial shaded sites in the middle of the forest and I have never had an issue charging. I am also looking into replacing the panels on the 5th wheel with similar panels and a better controler to improve their performance.

Steve