Resources
Technical notes
What you need to know to understand plant performance, explained plainly and with the formulas.
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What is performance ratio (PR) and how do you read it?
Daily energy alone does not tell you whether a plant is healthy. PR judges output against that day's sunlight.
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How to spot soiling losses in a PV plant
Soiling builds up silently and never raises a fault alarm. Knowing the traces it leaves in the data helps you decide when to clean.
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Catching inverter faults early: zero output under sunlight
Every hour without production is energy lost for good. A simple, explainable rule makes a stopped inverter visible within minutes.
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How to calculate fresh air flow (DIN EN 16798-1)
How much fresh air a room needs does not depend on a single rule. The largest of the occupancy, area, CO₂ and air-change criteria governs.
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Heat loss calculation: the basics of TS EN 12831
Sizing a heating system correctly starts with knowing how much heat each room loses on the design day.