24V battery with 12V consumers

DIY
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We run a solar installation with a 12V/690Ah battery bank.

I plan to upgrade the capacity of this battery bank and would like to go to 24V simultaniously, but there are a number of small consumers running on 12V. Easy you think, just use a DC/DC converter, but …

The location of this installation is in Scandinavia, so during winter there is very little yield from the solar modules. Actually just enough to power one router and one surveillance camera directly from the battery.

The Orion-Tr 24/12-9 or 24/12-20 would add a minimum of 30/80 Ah per month. This could be digested with the planned upgrade of the battery, but I’d rather add a second camera than spending the additional capacity just for being on 24V.

Has anybody got a creative (extra low power consumption) idea on how to solve this?
​Or would tapping 12V directly from the battery be a solution?

Thanks your support is appreciated

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Taking directly from one battery will end with imbalanced batteries. Not a good situation.

A small DC-DC converter will be about 85% efficient so not a huge amount of loss there.

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Is your low energy yield due to snow or the lack of daylight?
Because of the snow, I have modules at a 90° angle on the façade, as no snow remains there.

Why the step up in voltage? I know, a degrees in amps, less mm²,… but are there any other consuptions than 12V?

DCDC side wise, I have a DDR-60GL-5 in my sytem whitch is using 6.9 mA under 24V by itself (testet by me). So in comparison to the Orion a fraction. This would lead to around 5Ah per month.
There are also two 12V version avalible.

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You could use a very small DC-DC converter to power your router and camera.

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You could also add a low-voltage disconnect board module, like the XH-M609 based ones that are really efficient when their input is turned off during low-voltage trigger. That way, all you equipment would work when on high SoH, and the 12V DC-DC converter-powered would be switched off when the voltage would drop below a threshold. Granted, that would be a bit difficult to achieve if using LFPs, however it still can be done.

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My low energy yield from solar is due to lack of daylight. The modules are on poles directly on the gable of the roof. For winter I put them upright, so they’re free of snow.

Regarding the step up in voltage - only illumination, router and camera are on 12V, all the rest is behind 2 inverters (small one for 24/7 and a large one to be switched on when needed). So you’re right, there isn’t really a necessity for increasing the voltage.

Thanks for the information regarding the DDR-60GL-5 - I’ll keep this in mind

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