The most expensive mistake in Moroccan industrial solar is no longer buying the wrong panel. It is building too much capacity. Law 82-21 lets you inject at most 20% of annual production. Anything above that is energy you produced and cannot sell on regulated terms. On a sunny roof in Casablanca or Tangier, that leftover generation is a direct hit to IRR.

Size to the weekday load, not to the empty weekend roof

A factory that runs two shifts from Monday to Friday and is quiet on Sunday does not need a plant that peaks at Saturday noon. The correct input is 12 months of interval data — ideally 15-minute or hourly — not last year’s total kWh divided by 1,580. Two plants with the same annual consumption can need very different arrays if one is 24/7 process and the other is day-only packaging.

Why the 20% cap changes the old rule of thumb

Before the decree, some developers still oversized “to be safe” and treated the grid as a free battery. That logic is closed. The buy-back tariff (0.18–0.21 MAD/kWh on MT/HV) is a fraction of the avoided retail kWh. Every extra module that only produces surplus is a module you pay for at capex prices and sell at wholesale scraps.

A disciplined design therefore maximises the share of production that is consumed instantly on site. Storage is not mandatory, but it becomes interesting when the load curve has a late-afternoon peak (typical of HVAC and some process lines) that solar alone will miss.

A simple sizing sequence

  • Build the annual load duration curve from real bills and, if needed, a logger on the incoming MV feeder.
  • Simulate hourly PV production for the exact tilt, azimuth and soiling of the site (Tangier is not Errachidia).
  • Iterate capacity until self-consumption is high and modelled annual injection stays inside 20%.
  • Only then add a storage or load-shifting case, if the extra capex still clears your hurdle rate.

What “1 MWp” actually means on a Moroccan site

Green Taqa’s public reference case — about 1,580 MWh per year for 1 MWp — is a useful order of magnitude, not a design. Coastal haze, dust from a phosphate or cement neighbour, and roof orientation will move that number. The feasibility study should show the self-consumption ratio, the residual grid bill, and the surplus MAD, separately.

If a vendor quotes a plant that injects far more than 20% on paper, the quote is not aggressive. It is misaligned with the law that has been in force since 9 June 2026.

Talk to Green Taqa

Green Taqa is a C&I solar PV developer and independent power producer based in Casablanca. We deliver turnkey EPC and Zero-CapEx PPA solutions, with a complimentary pre-feasibility study based on your actual electricity bills. No obligation.

Contact: +212 5 21 56 26 00 · info@greentaqa.energy · greentaqa.energy