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The Technical Availability is the period of time for which a plant can produce without downtime. The time during which the irradiance is above the MIT is taken into account. Planned downtime, such as service calls and maintenance, is not taken into account.
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TTotal = Total time in which the plant could produce (see also picture below).
TDown = Not planned time in which the production of the plant is down.
In words
Availability = total plant time minus total downtime this divided by total plant time multiplied by 100.
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