Yield assessments (YA) and Long-Term Yield Predictions (LTYP) are a prerequisite for business decisions on long term investments into photovoltaic (PV) power plants. Together with cost data (CAPEX, OPEX and discount rate), the output of a YA and LTYP (utilisation rate, performance loss rate and lifetime) provides to the financial investors the parameters needed for the calculation of the Levelised Cost of Electricity (LCOE) and to assess the cash flow model of an investment with relative Internal Rate of Return (IRR) and Net Present Value (NPV).

One of the most relevant question that the Task 13 has tried to answer in this report is the following: How reliable are YA’s? Seven highly skilled specialists did not arrive at the same result in the two benchmarking exercises. From an industry perspective, it would be beneficial if more “live” post-mortem analyses (i.e. comparison of the LTYP and measured data, every 5 years of system life) would be made and published.

They also conclude that together with the previous report , they have provided all the needed information to understand if one YA is more reliable than another and which input and output data must be provided by the assessor to reach this conclusion.

The report is available here