Abstract
Photovoltaic (PV) risk analysis serves to identify and reduce the risks associated with investments in
PV projects. The key challenge in reacting to failures or avoiding them at a reasonable cost is the ability
to quantify and manage the various risks. There are several interpretations of the concept of risk, but in
general risk can be defined as the probability of failure multiplied by the consequences of its failure.
Best practice guidelines to improve the operation of PV power systems are often only applied as long
as the recommended actions have advantages for the executors, the Engineering, Procurement,
Construction (EPC) and Operation and Maintenance (O&M) companies and for the investors whose
main interests focus on low risks and maximum profit from an economic point of view. This leads to the
key question: How can you demonstrate the effectiveness of measures and justify their application?
Because the technical best solution is not always the economic best solution. And before you are able
to evaluate the cost-benefit ratio, the following question arises: How to quantify the basic impact of
technical risks on performance and reliability?
In a first approach we reviewed scientific literature and technical reports to compare and assess the
common practices for quantifying the impact of technical risks. Limitations and challenges were
compiled and selection criteria defined for the four methods:
a) Failure Modes and Effects Analysis (FMEA)
b) Multi Criteria Decision Analysis (MCDA)
c) Reliability, Availability, and Maintainability (RAM) analysis
d) Cost Priority Number (CPN) method
The advantages and disadvantages of these methods are demonstrated considering the factors
maturity level and data availability, and as well an overview of common risk mitigation measures is
given.
The second part deals with 30 PV Failure Fact Sheets (PVFS) annexed to this report which summarise
some of the most important aspects to know about single failures. The target audience for these PVFSs
are PV planners, installers, investors, independent experts and insurance companies or anyone
interested in a brief description of failures with examples, an estimation of risks and suggestions of how
to intervene or prevent these failures. Besides the PVFS collection we used a PV Failure Degradation
Sheet (PVDS) as introduced in [1]. These requires much more detailed measured input data but are
able to provide statistics on degradation rates and power loss of PV systems based on failure types.