Lazy Daze Owners' Group

'I have too much solar capacity', said no one, ever......

We've been through this before, but...

Everybody's needs are different.  Some might be fine with a single panel.  For some, like me, 5 panels are barely enough.  I would rather have 6.  What you need depends on how you use your equipment, where you camp geographically, when you camp seasonally, and whether you are in campgrounds with hookups or whether you are dry camping.  When I ordered my rig, I knew I would need much more than two panels, so I requested no panels, and had AM Solar do the entire setup.

If you think your needs will be minimal, after calculating your daily energy consumption needs, or if you think you might need more than two panels some day, go with the single panel for now.  If you know you will need more than two, and can get the rig with none, do that, and have your system designed and installed with all matching panels, the right wiring, the right battery bank, the right solar controller, all matched so you get maximum efficiency.

If in doubt of your needs, the way to determine your energy consumption is to look at every single piece of electrical power, determine its consumption, figure how many hours a day you use it, then add that all up.  Take the maximum power a panel can provide and divide it by 2, because you will rarely get that power, except for midday, summertime, with the sun directly overhead on cloudless days.  Using the panel power you just calculated, assume 3 hours of charging in the winter, and 5 hours in the summer, with lower charge rates earlier and later in the day.  Then, knowing what you are likely to need, and what a panel can provide, you can estimate how many panels you will need.  If someone tells you you will need no more than two panels without going through the numbers, pay no attention.  Again, we are all different, and what works for one of us is not necessarily adequate for someone else.

Ken F in WY

Here's a photo of my former midbath's roof with six 100 W panels. Note that there's no "batwing" TV antenna and no satellite-TV dish. Since I don't have a TV, I removed them both. If I hadn't, I would not have been able to fit six panels. And as you can see, there's barely room to walk on the roof.

(The black and orange box just aft of the air conditioner is a Ridgid tool case that contains the tilt bars for the panels.)

"I did see someone that is running a mini-split AC totally off grid, but he had 8 panel's."

Be aware that a solar panel can generate anywhere from 80 watts to several hundred. So seeing that a rig has a certain number of panels doesn't tell you anything. What counts is how many watts it has.

Keep in mind that battery capacity must be matched to panel wattage. It won't do you much good to have a thousand watts of panels if you only have a couple hundred amp-hours of batteries. The most common rule of thumb is one amp-hour of battery per watt of solar panel.

And finally, when under a very heavy load such as running an air conditioner, lead-acid batteries perform well below their rated capacities. (Look up 'Peukert's law' for a technical explanation.) So even if you had a thousand watts of solar panels and a thousand rated amp-hours of batteries, you wouldn't get anywhere near a thousand amp-hours of service when running an air conditioner.

LiFePO4 batteries do much better with heavy loads, but now you're talking five times the cost.

I understand that the AM Solar installation package allows for tilting each panel. Have you found a need to do so and if so have you noticed an increase in solar gain?

$343 for 90 watts is rather costly--$3.81 per watt. By contrast, standard Renogy 100 W panels cost $1.08 per watt, and even Renogy's high-efficiency (= physically smaller) Eclipse 100 W panels are $1.79 per watt-