fiiting up a solar panel to van

I presume you would have a hotwire running from your car alternator to charge the batteries whilst driving? if that is the case, all you need to do is chop the alligator clips off the solar panel cables and put an Anderson plug on just like the one you should have coming from the alternator>batteries. Done. So whilst driving, you have them charging and when camped, disconnect the car/alternator plug and plug in your solar panels instead. Like Rooster, I'm no genius with this stuff but that is pretty easy to do. If you don't have a "hotwire" running from alternator to van batteries, you ought to have one put in. Not really expensive.

Ah! the old 'hot wire' from the Alternator to the charge the batteries trick.

Absolutely fascinating - now top of my 'to do' list.

Thks for that and as you said - 'you don't have to a genius with this stuff'

DD

Thanks Guys, Yes I agree,it can,t be that hard. My auto man wants $150 to do the job (includes $50 for a set of anderson plugs that are available on E Bay for $14 and are genuine). Thanks again johno

We do have a deep cycle Batt that charges as u drive , so assume it has a hot wire. The problem with this method of charging your battery is that it will ONLY charge it to 80 % thus the need for a solar panel jhono

Although not entirely true, even taking the 80% thing as gospel, (there's plaenty about that in the archives) you still have a good foundation to build upon. Your solar, if you have enough of it, and sun, can charge you up to 100%. Some like to fix their panels to the van roof, which is a handy way to store them and pretty secure but means you have to park in the sun and if shade creeps over, your charging is over. I have a longer lead from panels to the Anderson socket on the van (that also plugs into the hotwiree to the alternator) and am able to move the panels around with the sun. Not as convenient as you have to store them when not in use and you have to make sure they are theft proof or at least theft resistant. Neither is difficul though.

Thanks Steve, Never thought about the problem with shade etc, I like the idea of being able to move the panel wherever u want for max sun Thanks

Thanks Ross, The Panel has a regulator and just trying to determine whether it has a multi stage charging system which apparently is the way to go. Can u advise? There is certainly a lot might to Solar and Batteries than first meets the eye !!! Some are saying MPPT regulators are best? What does that mean? Thanks again johno

Hi Johno,

you can use an alternator as a charging source for your house battery.

But solar is a smarter choice in that it provides ample voltage, which isn't always true for car alternators.
Having said this, any car alternator will put 'some' charge into your battery.
Remember, alternators were designed to keep an almost fully charged battery full - they're not suitable to bring a reasonably discharged 'deep cycle' battery back to 100% full charge.
And never charging a battery to 100% means reduced battery life.

So you're asking what are MPPT solar regulators:
these units basically convert voltage from the panel to charging amps.

Ordinary PWM solar regulators just provide a switching function between panel and battery: either the panel is connected (on) or disconnected (off), and the on/off happens rapidly, sometimes over hundred times per second.
This process isn't very efficient, because the solar panel cannot output maximum charging power when directly wired to the battery (even for short times).

MPPT solar regulators on average achieve a 20% higher charging power/current from the same panel compared to an ordinary PWM solar regulator.

Look for a multistage charging capable MPPT regulator, ideally with battery temperature sensor, and optimised charging algorithm. The latter enables the regulator to precisely charge the battery to 100%, regardless of any load drawing power during charging.
If that's not done precisely and correctly, the battery either gets over- or under-charged, shortening its life.

One word of caution: there are quite a few PWM solar regulators being marketed as MPPT by unscrupulous Australian and overseas sellers.

To see a good example of a well designed MPPT solar regulator, just follow the link next to our logo.

cheers, Peter