More and more African businesses are shifting toward solar energy solutions due to declining solar equipment costs.
The biases in the estimation of solar production in Africa can lead to up to a 20pc reduction in savings for African businesses and a 1-2pc reduction in the internal rate of return (IRR) for solar developers and investors, a report by CrossBoundary Energy titled, Measuring Solar Irradiation in Africa has concluded.
“For most commercial and industrial (CI) clients, a major factor in awarding projects is the electricity tariff and resulting savings offered. An often-overlooked factor is the estimated solar irradiation on site, which can have a significant impact on forecasted production and, thus, expected savings.” Lenny Matei, co-author and Senior Project Engineer at CrossBoundary Energy, says.
Data from an analysis conducted at operational sites in Nairobi, Kenya, and Accra, Ghana, revealed that actual irradiation which is measured by project ground-based measurement systems, deviated 3-5pc from the satellite data widely accepted as accurate for making production forecasts during solar design. This translated into an equal deviation of 3-5pc in solar power production estimates, while all other factors are held constant.
The report also states that sites outside of major cities experience even higher biases. According to the data, due to variable microclimates created by diverse topography, satellite solar irradiation estimates for sites nestled in highlands, valleys, or next to lakes can be biased by up to 20pc. The findings are in line with kWh Analytics’ inaugural 2020 Solar Generation Index Report, which found that that 25pc of U.S. solar projects surveyed missed their 3-year forecasted production targets by over 10pc.
The report further shows that as a result of systems underperforming their production estimates, CI clients in African metropolitan areas could fail to realize 4-5pc of their projected savings from solar, while those outside major cities risk savings reductions up to 20pc.
The risk is far higher for off-grid solar customers, such as mining companies, which use generators to supplement renewable power and could carry unexpected increases in fuel costs to offset unmet power needs.
For investors, such systemic underperformance can reduce the projected IRR by up to 1pc for urban sites, while diverse portfolios of urban and rural assets could see deviations from the projected IRR of greater than 1pc.
“Until we all recognize the shortcomings of how we currently forecast, the growth of the African distributed solar market as a whole – and its promise to neutralize the carbon footprint of the continent’s growing industries – rests on a fractured foundation.” Phuthi Tsatsi, co-author and Business Development Associate at CrossBoundary Energy says.
“By highlighting this issue, we aim to begin a broader conversation about how to raise the CI industry standard for solar production forecasting to deliver better outcomes for clients.”
The report recommends collaborative actions that African solar developers and data providers can take to improve African irradiation estimates over the long term, but also practical steps CI solar buyers and investors can implement on their own to protect themselves against over-optimistic production estimates.
These include ideas such as requiring disclosure of irradiance estimates as part of competitive tenders or investing in on-site weather stations.
Kathleen Jean-Pierre, co-author and Vision and Delivery Lead for CrossBoundary Energy says, “Responsibility for improving solar irradiance assessment on the continent does not lie with a single player. We believe it should be addressed collaboratively, with input from solar developers, data providers, customers, and investors.”
Africa’s CI solar industry can support the continent to recover faster and cleaner after the Covid-19 pandemic. For this to happen, CI solar customers, developers, and data providers must act together to better interrogate and ultimately improve solar irradiation assessments.