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NREL / EnergyPlus

EnergyPlus™ is a whole building energy simulation program that engineers, architects, and researchers use to model both energy consumption and water use in buildings.
https://energyplus.net
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PhotovoltaicPerformance:EquivalentOne-Diode: litterature/module out of date? #5285

Open jmarrec opened 8 years ago

jmarrec commented 8 years ago

based on: https://unmethours.com/question/12243/using-the-cec-performance-database-data-for-solar-pv-in-e/ and @EnergyArchmage answer.

I'd also like to know if this is indeed the same as the CEC model... I've been trying to map CEC field to the E+ one, and some do match, but others don't like TauAlpha, Bandgap, heat loss coeff and total heat capacity are unclear to me (latest two are only for BIPV as I understand it)

Also, it seems that "Cell Type", which is a required input (though that's not reflected in the IDF Editor it will throw an error if blank here), isn't even used anywhere.

The rationale might have been to use a dropdown to preset values such as eV etc?

jmarrec commented 7 years ago

This just popped up again today (here): can we get this clarified?

mjwitte commented 7 years ago

@EnergyArchmage ?

EnergyArchmage commented 7 years ago

I don't know what CEC is doing, need a CA person who is up to speed on that program. I suspect it is all the same trnsys model but I cannot confirm. Need a trnsys person to figure thisout.

IMHO the one-diode implementation in E+ needs to be completely redone, but that has never been funded.

nealkruis commented 7 years ago

CEC is now using a modified version of the PV Watts algorithms. They have since moved on from the Beckman approach used in the original model. The Beckman approach is a variation of the 4-parameter model which is used in the one-diode implementation.