Lesedi Solar Care Business Plan — The Soiling Problem & Value Proposition

Soiling is the accumulation of dust, sand, pollen, agricultural spray drift, industrial fallout and bird droppings on module glass. It scatters and absorbs…

The Soiling Problem & Value Proposition

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4.1 What soiling costs an owner

Soiling is the accumulation of dust, sand, pollen, agricultural spray drift, industrial fallout and bird droppings on module glass. It scatters and absorbs incident light before it reaches the cell. The effect is continuous, non-linear and highly site-specific: rates depend on particulate load, tilt angle, humidity, wind and rainfall patterns. In South Africa’s semi-arid solar corridors, long dry seasons allow deposition to build for months without natural washing.

Figure 6. Annual soiling loss by site context.

Site context	Typical annual soiling loss	Peak dry-season rate
Northern Cape utility plant (arid, dusty)	6% – 9%	up to 1.0%/week
Free State / North West (agricultural)	4% – 7%	0.6%/week at harvest
Coastal Western Cape (salt, wetter)	2% – 4%	0.3%/week
Urban C&I rooftop (industrial fallout)	3% – 6%	0.5%/week

4.2 The arithmetic clients can verify

StrengthA 75 MW plant: the client is cash-positive on the cleaning benefit alone

A 75 MW plant generating roughly 172 GWh a year at an average realised tariff of R1.05 per kilowatt-hour produces approximately R180 million of annual revenue. A 5.8% recovered-yield improvement from a disciplined cleaning programme is worth about R10.4 million a year to the owner. Lesedi’s full-service contract on that plant is priced at R7.1 million. The client is cash-positive on the cleaning benefit alone, before counting availability improvements, fault detection, warranty preservation and avoided module replacement. This is why the sale is a data conversation rather than a price negotiation, and it is the single most important commercial fact in the Plan.

4.3 Beyond cleaning: the full loss stack

Loss mechanism	Lesedi intervention
Soiling	Scheduled cleaning cycles calibrated to site-specific soiling rate measured by reference cells
String and combiner faults	Continuous LumenIQ monitoring with automated deviation alerts and dispatch
Inverter downtime	Preventive servicing, spares pooling, guaranteed response times under SLA
Module defects (hotspots, PID, cracking)	Annual drone thermography and IV curve tracing; warranty claim substantiation
Tracker misalignment	Mechanical inspection and calibration within the preventive schedule
Vegetation and shading	Managed vegetation programme integrated into the site plan
Theft and damage	Perimeter integrity checks; incident escalation protocol

The breadth of this stack matters commercially as well as technically. Cleaning is the entry point because it is easy to price and easy to prove, but the recurring revenue and the switching costs come from the full stack. An owner who has handed over monitoring, fault dispatch, warranty substantiation and vegetation management does not change supplier lightly.