Guide · Equipment
Monocrystalline or polycrystalline? String or micro-inverters?
These two questions come up as soon as you compare quotes, but for most Moroccan homes one of them is already settled. Here's how much each one actually deserves to keep you up at night, and why.
The panel: a question that's basically settled
Honestly, the mono-versus-poly choice shouldn't take up much of your time. Monocrystalline has won. A monocrystalline panel is cut from a single silicon crystal, giving its cells a uniform structure and an efficiency of 19 to 22 % on current models: every square metre produces more than a poly panel of the same surface. On a tight or oddly shaped roof, that translates directly into extra kilowatt-peak without enlarging the installation.
It also handles heat better. All panels lose a bit of power as temperature rises — that's semiconductor physics — but monocrystalline resists this thermal degradation better. In Marrakech or Agadir in high summer, that matters during the hottest hours.
Polycrystalline, meanwhile, was the standard until the mid-2010s: cells made from several fused crystals, bluish look, efficiency of 15 to 17 % and more pronounced heat sensitivity. With prices having converged, it's no longer the default choice. It's still available, but in practice we install monocrystalline — and that's what you'll see on nearly every serious quote today. In short, on this point, your real decision-making work lies elsewhere.
The inverter: this one deserves your attention
We install string inverters, and only those: Deye and Huawei. String architecture wires several panels in series to form a "chain" that feeds a centralised inverter. It's simple, proven and cheaper to install. Its weak point is well known: if one panel is partially shaded — an antenna, a shared wall, a chimney — it drags the whole chain down, like the weak link in a rope.
That's precisely why your roof's shape weighs more than the budget in this choice. Some string inverters, including the Huawei SUN2000 range we install, integrate per-string optimisation that partly mitigates the effect of shading. On a clear roof, well oriented and without recurring shade — the most common case in Morocco — a string setup is more than enough and remains the most rational choice.
What about micro-inverters? What you should know
You'll surely come across the terms "micro-inverters" and "optimisers" in your reading, and it's useful to know what they do — even though it's not what we install. A micro-inverter is a small converter mounted behind each panel: each module works independently, shading on one no longer affects the others. The power optimiser is a variant: also installed panel by panel, but connected to a central string inverter. Both allow fine-grained, panel-by-panel real-time production monitoring.
Their value is concentrated on truly difficult roofs: broken up, facing several directions, or subject to partial shading for a good part of the day. The trade-off is a higher cost and more components on the roof, so more parts liable to age. For configurations where these solutions are called for, it's better to turn to an installer who has made them their specialty. On the vast majority of Moroccan roofs, the right pairing remains high-density monocrystalline on a string inverter.