Simulating Sudan's Climate in London: How We Solved Solar Efficiency Loss in Extreme Heat

Standard solar PV modules lose output in extreme heat. We partnered with London South Bank University to test a cooling solution for Sudan's climate.

The Problem We Kept Running Into

Sudan receives over 3,000 hours of sunshine per year. On paper, it is one of the most favourable locations on earth for solar photovoltaic generation. In practice, there is a problem that anyone who has installed PV systems in equatorial climates understands: extreme heat reduces module efficiency.

Solar panels are rated under Standard Test Conditions — 25°C cell temperature, 1,000 W/m² irradiance. In Sudan, ambient temperatures regularly exceed 40°C, pushing cell temperatures far beyond rated conditions. The result is measurable power loss at precisely the times when irradiance is highest.

This is not a theoretical concern. It is something our engineering team encountered repeatedly in the field. When we secured a project through the African Development Bank to install and commission 37 off-grid solar systems across Sudan, we needed a solution that was technically sound, affordable, and deployable at scale.

Taking Sudan's Weather to London

Testing PV performance modifications in Sudan would require a minimum of one year of field data collection — accounting for seasonal variation, dust conditions, and the logistics of operating measurement equipment in remote locations. We needed a faster path to validated results.

Through London South Bank University's Sustainable Innovation Programme, we gained access to LSBU's environmental testing chamber — a controlled facility capable of simulating specific temperature, humidity, and irradiance conditions on demand. What would take a year in the field could be replicated in two weeks.

The programme provided the full instrumentation suite: a solar array to simulate sunlight, a power inverter for DC-to-AC conversion, load resistors to manage excess power, a solar power meter for radiation measurement, and a solar tester for electrical data collection. Working alongside LSBU researcher Abdullah Qaban and the Built Environment and Architecture School's laboratory team, we designed a series of controlled experiments to isolate the variables affecting output in hot-climate conditions.

What We Found

The testing confirmed what our field experience suggested: as module temperature increased beyond rated conditions, electrical output declined in a predictable and measurable pattern. But the more significant finding was what reversed it.

We discovered that the application of water cooling combined with a fine sand layer on the panel surface produced a measurable increase in efficiency under high-temperature conditions. The sand layer acts as a passive thermal management surface, while periodic water cooling addresses acute temperature spikes. Both materials are abundantly available in the regions where these panels are deployed — this is not a solution that depends on expensive imported components.

The environmental chamber allowed us to test multiple configurations rapidly, isolating the contribution of each variable and establishing performance baselines that would have been impossible to achieve with the same precision in field

Why This Matters Beyond Our Projects

The efficiency loss from overheating is not unique to Sudan. It affects every solar installation operating in the Sunbelt — across the Sahel, the Arabian Peninsula, South Asia, and northern Australia. Any technique that demonstrably recovers lost output in these conditions has implications for gigawatts of existing and planned capacity.

For project developers calculating energy yield projections, even a few percentage points of recovered efficiency compound significantly over a 25-year asset life. For off-grid installations powering clinics, schools, and water pumps, it can mean the difference between a system that meets demand and one that falls short during peak afternoon hours.

The data and testing reports generated through the LSBU programme also provide the documented, third-party-validated evidence that regulators and financing bodies in Sudan require before approving new technology for

What Came Next

The partnership with LSBU produced outcomes beyond our own project requirements. The research strengthened the university's laboratory capabilities in renewable energy testing and provided valuable industrial experience for their research team. Two additional companies working on solar PV solutions for challenging climates subsequently applied to the Sustainable Innovation Programme — a direct result of the work we initiated.

For our team, the findings have informed how we approach system design for hot-climate installations. The cooling technique is one tool in a broader engineering toolkit that includes panel selection, mounting angle optimisation, inverter specification, and maintenance scheduling calibrated to local dust and temperature

Building on Evidence

Sudan's 60% electricity access gap will not be closed by a single technique or a single project. It will be closed by engineers who understand local conditions, test their solutions rigorously, and build systems designed to perform — not just on day one, but across decades of operation in some of the most demanding climates on earth.