Field survey insights and performance assessment of water-in-glass evacuated tube solar water heaters in Burkina Faso

Water-in-glass evacuated tube collectors (WiG-ETCs) now dominate Ouagadougou’s solar water-heating market as locally manufactured flat plate collectors (FPCs) continue to decline. This study evaluates the relevance and long-term viability of WiG-ETCs in Burkina Faso by assessing their potential, challenges, and prospects for sustained adoption. A field survey of 31 operational systems in Ouagadougou—24 households and one seminary—was conducted in April 2024, supported by a literature review and market analysis. The inspection covered system functionality, maintenance history, tank material, tilt angle, and visible signs of deterioration. Results show that 94% of systems were operational at the time of the survey. The most frequent issues were malfunctioning float valves (35%) and water leakages (29%). Stainless-steel tanks demonstrated markedly higher durability, with several systems operating for more than 14 years. User satisfaction was high: 97% of respondents reported being satisfied with their investment, and 74% reported year-round hot-water availability. Older or rust-affected systems exhibited greater maintenance needs. Overall, WiG-ETCs demonstrate high operational reliability and strong user satisfaction in Burkina Faso. To secure this potential, key priorities include addressing prevalent float-valve failures and promoting corrosion-resistant stainless-steel tanks to enhance system longevity.