Solar Trickle Charge Ideas

Hi all,

I have a business that runs a fleet of vehciles (mainly hiluxes and landcrusiers) in remote locations in WA. Sometimes, between jobs or on the off season these vehicles get left on site or at an airport and not driven for weeks, sometimes months on end. As a result we quite often have flat batteries which is inconvenient and not great for the batteries no doubt. We run dual batteries but more often than not both a flat particularly if left a couple of months.

I'm thinking about putting in solar trickle charger into each vehicle to keep a charge up to the primary battery. Hoping to get some ideas from you all around the following points;

- Panel options: size (considering 4w) and type
- Panel mounting: prefer a permanent mount either on the lightbar (mine spec), or internally, say on the dash somehow (velcro) or stuck to passenger windscreen??
- Regulator: been considering the monrningstar sunguard 4A 12v
- Wire, connectors, fuses: guage and ideas would be appreciated.

Hoping to get some good advice and experiences from anyone that has done the same. Thanks in advance.

Will.