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# Schedule for Photovoltaic Efficiency in Simple mode

How can I create an schedule for energy efficiency to add in the "PhotovoltaicPerformanceSimple" using the Conversion mode scheduled depend on the temperature of the surface of painel? I want to relate the surface temperature (or at last the temperature of wheather file) to the effiency of the painel. Could be with a equation or a table of temperature x = efficiency y. It is possible? I want to compare some different tecnologies production.

Thank You.

Henrique Lauffer

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If you want to use the PhotovoltaicPerformance:Simple option, then I would suggest to run two simulations:

• The first one is to obtain the surface temperature, by reporting the Surface Outside Face Temperature on a Timestep level. Make sure, that the modeled surface has similar construction materials to a PV panel's materials. Once you have this, you can calculate the efficiency of the PV system in excel for every timestep and save it in a .csv file. In the documentation of SAM equation 9.32 can help you determine, how change in temperature changes the efficiency. This equation is using cell temperature, which is usually 0-3 degrees higher, than the surface temperature.
• Then you can import the .csv to EnergyPlus with the Schedule:File object and run the simulation again, with the new efficiency schedule to get the PV output.

An other option is, to go for a more detailed PV model, like PhotovoltaicPerformance:EquivalentOne-Diode or PhotovoltaicPerformance:Sandia which have the temperature dependency already built-in. I would only suggest to go for this option, if you now exactly what type of PV modules you have, and you can get their exact parameters from the Sandia or CEC database.

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Thanks, this input schedule with file helped to get the efficiency hourly. The photovoltaics are simulated by shadow surface, instead of modeled the surface with similar construction materials, can I get this temperature of the shadow surface? Thanks

( 2019-01-27 09:30:35 -0500 )edit

e+ doesn't calculate the temperature of shading surfaces. For the first simulation to get the temperatures, in Sketchup-Euclid you can make a new zone and copy-paste the shadowing surfaces there, and delete the original shade surfaces. e+ might throw a warning due to non-enclosed zones, but the simulation should be fine.

( 2019-01-28 02:57:52 -0500 )edit