Solar Chargers

[Gad-Westy]

Google has failed me on this so over to PH.

Having recently had a new driveway installed at the top of our garden, I've started parking our least used 'proper' car up there. The car is sometimes used a few times per week but there are periods where it can sit for 3-4 weeks without moving and I worry a little about battery drain. In the past, I used to deal with this sort of scenario by having a bluetooth battery monitor installed that would ping alerts to me if the battery was depleted. Great though that was, it won't work for me now as the car is out of bluetooth range and though I'm probably near it most days in summer, in winter I'll typically not be out in the garden much. Eventually there'll be a garage up there with electricity and this problem will go away but for now I'm looking for other options.

Anyway, long story short, how about a solar charger or two? The car is a BMW 5 series touring so I could fit a solar charger to the rearmost side window/s and leave it there permanently without it being in the way but could I maybe use two and have one both sides to maximise coverage or could that cause issues?

Any particular model I should opt for is any old thing from amazon as good as anything else?

[swamp]

3-4 weeks should be absolutely no problem for most car batteries.

If you're worried, get a lithium jump starter.

[ssray]

As you are probably aware, most if not all modern cars have parasitic drain, something is always on GPS etc.

If the battery gets too low on charge you won't recover it.

We have a AA solar panel, it was given to us, it seems to work well, it will hopefully at least mean the battery lasts a lot longer

[Gad-Westy]

swamp said:

3-4 weeks should be absolutely no problem for most car batteries.

If you're worried, get a lithium jump starter.

Cheers but I have found that 4 weeks can be pushing my luck even on a fresh battery. There is quite a bit of parasitic drain going on in modern cars and letting an AGM battery go too flat can be an expensive mistake.

[Gad-Westy]

ssray said:

As you are probably aware, most if not all modern cars have parasitic drain, something is always on GPS etc.

If the battery gets too low on charge you won't recover it.

We have a AA solar panel, it was given to us, it seems to work well, it will hopefully at least mean the battery lasts a lot longer

Cheers. Do you know if there is any reason I cannot use two solar chargers? It would be useful if I could because of the direction the car is generally parked in relation to the sun, especially in winter.

[littleredrooster]

I use one of these in the MX-5.

Solar charger

Placed in the windscreen (which faces due South) and plugged into the OBD socket, it keeps the battery nicely charged when the car is not in use.

[ssray]

Gad-Westy said:

Cheers. Do you know if there is any reason I cannot use two solar chargers? It would be useful if I could because of the direction the car is generally parked in relation to the sun, especially in winter.

It would depend on how the wiring in the car, in theory you could get 24volts depends how they are wired up.

One should be sufficient, you are only adding a trickle charge but it should be only loosing a little

[Gad-Westy]

Thanks both