Go Power Overlander-E 200W Monocrystalline Expansion Solar Panel

The Go Power Overlander-E is the expansion panel built to grow an Overlander solar system you already own. If your rig came with the Overlander 200-watt kit and you're finding that a single panel runs out of daylight before your batteries are full, this is the piece that adds a second monocrystalline module without changing how your controller is wired. It pushes another 200 watts and up to 9.62 amps of charging current into the same 12-volt bank.

Here's the part people miss, so we'll say it up front. This is an expansion panel, not a complete kit. There's no charge controller in the box and no cabling run to your batteries. It's designed to bolt on next to an existing Overlander array and tie in through the included MC4 expansion connectors. If you don't already have an Overlander kit with its controller installed, you'll want the full kit first, then come back for this to expand. Buy it as your second or third panel and it drops right in.

The panel itself is monocrystalline, which is the cell type that gives you the most watts per square inch. That matters on a roof, where space is always the limiting factor. At 59.1 inches long, 26.3 inches wide, and just 1.58 inches thick, it sits low and flat. The low profile keeps it out of the wind and out of the way when you're up top cleaning or stowing gear.

Mounting is screw-mount, flush to the roof, using the hardware that ships in the box. That does mean drilling into your roof, so plan your layout before you commit. Most folks lay the panel out, mark the feet, and seal every penetration with butyl tape and a good self-leveling sealant. Do that once, do it right, and the panel will ride out years of highway wind and weather. The feet raise the panel just enough for air to move underneath, which helps the cells run cooler and hold output on hot afternoons.

Because this expands the Overlander system, the whole array grows with it. The Overlander platform is built to expand up to 600 watts total, so you can run two or three of these panels off the same controller as your power needs climb. That's the appeal for anyone living out of a van, trailer, or camper for weeks at a stretch. More panel means more amp-hours back into the bank each day, which means running the fridge, charging tools and laptops, and topping off house batteries without firing up a generator or plugging into shore power.

Wiring in is meant to be quick. The MC4 expansion connectors snap into the leads coming off your existing Overlander panel, running the new module in parallel so both feed the same controller. Keep both panels in the same orientation and you'll avoid mismatched output between them. It's the kind of upgrade you can knock out in an afternoon once the roof holes are drilled and sealed.

Who's this for? Anyone who already went solar with the Overlander and outgrew a single panel. Full-time RVers, weekend boondockers, overland and van-life builds, and off-grid trailers all land here eventually. The math is simple. One 200-watt panel is a great start, but a second one turns "we have to watch the battery monitor" into "we barely think about it." If you dry-camp in shade or short winter days, the extra panel is what keeps you off the generator.

A couple of honest notes. Real-world output depends on sun angle, temperature, and shade. The 9.62-amp figure is the panel's rated charging current under full sun with the matching Overlander controller doing its job. Partial shade from a roof vent, an antenna, or a nearby tree will knock output down more than you'd expect, so mount it where it gets clean, open sky. And size your wiring for the run. Long cable runs on undersized wire cost you voltage and amps before the power ever reaches the battery.

The Overlander-E ships with the panel, the mounting hardware, and the MC4 expansion connectors you need to tie into your existing Overlander module. Add it to a system you trust, and you've got a clean, straightforward way to double your solar without re-engineering the whole install.