I've planned a small array of 4 panels on a toy-hauler (link to panels). At minimum it would need to provide for a bunch of PoE cameras w/nvr, a hotspot router, and cordless tool batteries. Hopefully it well outperforms, and I can stack a bunch more loads later. Shading & indirect light is a big concern of mine. This is a work trailer, and sometimes I will have to park in a less than ideal locations for several days. Yes, obviously generators/upgraded-car-alternators could do me wonders, but come-on... if that's how we were, we wouldn't be here. Also, I will not be hauling it daily. The security is not only for the trailer but also it's surroundings.
To combat this I plan to use the following:
1) A baby MPPT dedicated on each panel: Victron 75|15
2) 12V battery bank (generic)
3) A fan to push air from the trailer to behind the panels when panels trip over a certain temperature.
My reasoning on part 1 should be self explanatory. Part 2 is based on the fact that because the controller needs battery bank voltage + 5V, think this will massively extend the range of time it can collect and improve collection on lower light situations.
My concerns are:
1) I have to boost back up to 48 Vdc to run the camera system. That being said, 48 Vdc pairs nicely with a lot of stuff anyway and will help me save on other losses.
2) I have read literature which suggests that panels will tend to hug their max power voltage & limit their amperage during low light conditions which should indicate that achieving +5V won't actually be that hard on 24 Vdc even with all panels on a dedicated MPPT.
3) If I try to straight to 48 Vdc, I would need to do a 2S2P or 4S configuration. This could eliminate several components and complexity if I am trying to dream up a way to squeeze energy which won't be effective.
4) Is the fan even worth it? What temperature should I set it to? I would have it only cut on when power generation is significant enough anyway. Perhaps a few fans would make a mediocre dump load? It would also keep the contents in the trailer a lot cooler too. I have my doubts if this would help AT ALL though.
Also, bonus question: Would hacking my tool battery chargers to charge directly from DC to DC via a boost or buck converter be worth it? Or should I just use the DC-AC-DC and keep the computer/electronics that were designed to be used with the batteries at eat the losses.
To combat this I plan to use the following:
1) A baby MPPT dedicated on each panel: Victron 75|15
2) 12V battery bank (generic)
3) A fan to push air from the trailer to behind the panels when panels trip over a certain temperature.
My reasoning on part 1 should be self explanatory. Part 2 is based on the fact that because the controller needs battery bank voltage + 5V, think this will massively extend the range of time it can collect and improve collection on lower light situations.
My concerns are:
1) I have to boost back up to 48 Vdc to run the camera system. That being said, 48 Vdc pairs nicely with a lot of stuff anyway and will help me save on other losses.
2) I have read literature which suggests that panels will tend to hug their max power voltage & limit their amperage during low light conditions which should indicate that achieving +5V won't actually be that hard on 24 Vdc even with all panels on a dedicated MPPT.
3) If I try to straight to 48 Vdc, I would need to do a 2S2P or 4S configuration. This could eliminate several components and complexity if I am trying to dream up a way to squeeze energy which won't be effective.
4) Is the fan even worth it? What temperature should I set it to? I would have it only cut on when power generation is significant enough anyway. Perhaps a few fans would make a mediocre dump load? It would also keep the contents in the trailer a lot cooler too. I have my doubts if this would help AT ALL though.
Also, bonus question: Would hacking my tool battery chargers to charge directly from DC to DC via a boost or buck converter be worth it? Or should I just use the DC-AC-DC and keep the computer/electronics that were designed to be used with the batteries at eat the losses.
