Harmattan and Solar: What Seven Years of Data at Abba's Heart Tells Us

Every year between September and February, the harmattan wind carries Saharan dust across West Africa and cuts solar irradiance across Lagos by 15 to 25 percent. Most system sizing calculations in Nigeria either ignore this or guess at it.

Abba's Heart Montessori School has been generating real data on the question since 2019, when its 200kWp off-grid installation went live. That makes it, unusually, a school with seven full harmattan seasons of operating history already on the books before SPARC+CM's own six-month monitoring programme even begins.

From September 2026 to February 2027, that monitoring programme will combine Abba's Heart's historical performance with new instrumentation to produce the first independently validated harmattan season solar performance dataset for a commercial-scale Lagos school installation.

The output will be published in March 2027 as the open-source Harmattan Resilience Protocol: a free, practical sizing methodology for any Nigerian solar installer, whether or not they ever work with SPARC+CM.