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When you use the TiltAzimuth option, the irradiance calculation is detached from your model geometry. It assumes shade-f

I think the simplest way to do it is in post-processing. You can define output variables for electric generation and con

If you want to use the built-in PV models of e+, then using e+'s own irradiance model should be fine to use, because the

With the SurfaceProperty:HeatBalanceSourceTerm object you can add an additional heat source to the outside or inside bou

e+ doesn't calculate the temperature of shading surfaces. For the first simulation to get the temperatures, in Sketchup-

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

You can find it on pg. 145 in the EnergyPlus I/O reference. The nodes are numbered from outside to inside.

If you have a decent amount of insulation, the effect of this on the thermal load of the zone is very small. Especially

If all you need to edit in the IDF is the schedules, go with Jason's suggestion. That is a more straightforward way to d

You can find plenty of ideas here and here.

You can find plenty of ideas here and here.

Try reporting the EMS variable with Timestep frequency instead of hourly. Probably the values are calculated correctly,

Try reporting the EMS variable with Timestep frequency instead of hourly. Probably the values are calculated correctly,

It is probably a problem with the Python IDE you use. If you use Canopy, make sure you have the eppy package installed i

It is probably a problem with the Python IDE you use. If you use Canopy, make sure you have the eppy package installed i

If there is a shadow on an exterior surface, the shadowing algorithm calculates the sunlit area of the surface. It doesn

I think it is subtracted for f != 0, because the motor does two things with the electric energy it consumes: 1) dissipat

If a large portion of the mechanical power of the impeller would be converted to rotational energy, the the fan would co

If a large portion of the mechanical power of the impeller would be converted to rotational energy, the the fan would co

If a large portion of the mechanical power of the impeller would be converted to rotational energy, the the fan would co

Fan Heat Gain Calculation I'm looking into the fan heat gain equations in the engineering reference guide, but I don't u

There was in the large model. However in the dummy model (see Edit part), where I reproduced the error, there wasn't any

There was in the large model. However in the dummy model (see Edit part), where I reproduced the error, there wasn't any

EnergyPlus probably calculates irradiance on shading surfaces if necessary, e.g. for reflections, but looks like it does

Have a look at this discussion: https://unmethours.com/question/15156/can-energy-plus-simulate-directly-semi-transparent

You can report the Surface Outside Face Incident Solar Radiation Rate per Area output variable.

Why is a simulation necessary? You can do it with Excel.

In the winter the slab would preheat the return water from the terminal units, before it goes to the heat pump, to reduc

(contd.) - Read the Surface Outside Face Incident Solar Radiationfor the surface you keep. - Calculate the amount of g

The workaround described above is just an idea. Unfortunately I don't have a working model. But if I had to do it I woul

One possible (and cumbersome) workaround to move a surface, may be to define multiple Shading:Building:Detailed in the s

Instead of using shading, you could set up a Surface Property Solar Absorptance EMS actuator for the roof surface, and

"What I actually need to know is the material that constitutes the frame or its thickness just by knowing the informatio

You can get this data from Berkeley Lab WINDOW, if you model the window there.Be careful with U, it is the heat transfer

I think Frame Conductance here really is just the conductance of the frame per square meters. Maybe it's just me, but wh

I think, with BCVTB you can do this. Check out this: https://unmethours.com/question/18627/bcvtb-how-to-install-new-pyth

It may be because of Sizing:Parameters Cooling Sizing Factor. I think the default value is 1, but maybe it is 1.3 in your idf.

I assume, that you refer to the ElectricLoadCenter:Generators object. As it says in the Input Output Reference:

"This value [Generator Rated Electric Power Output] is used only for supervisory control and generator dispatch; the actual power output for each time step is determined by the generator models."

So the power output comes from the PV models. I think, this value is only needed for something like: how much generated electric power should the Electric Load Center "expect" from the PV models, to manage storage and other things. If your setup is relatively simple, e.g. you have only one generator object, no storage, the value of Rated Electric Power Output may have no effect on your results. Just set it to the sum rated power of your PV system.

I'm afraid you can't calculate that. You have to get that information from the designer of your exact PV system. If it is not designed yet, or that information is not available, maybe you can guess from the type of the inverter:

If you know, that your inverter's nominal voltage is e.g.: 51 V, then you can assume, that there are 3 panels in series, because your panel's max power voltage is 16.9V and 51 / 3 is almost 16.9. So in this case the Number of Modules in Series will be 3 and the Number of Series Strings in Parallel will be the sum number of your panels / 3.

If you don't know anything about your inverter, then use an ElectricLoadCenter:Inverter:Simple. In this case maybe (this is just my guess) the voltage and current figures of the whole array are irrelevant, because maybe (this is just my guess again) e+ uses the voltage only to calculate inverter efficiency in case of a more complicated inverter object, like ElectricLoadCenter:Inverter:LookUpTable

Generally if you have limited available information on the systems that you want to model, use simple models, because sometimes increasing complexity may just increase overall estimation error:

NREL's System Advisor Model contains a library for this, which you can download separately here, in csv, at the bottom of the page.

With Pandas library in Python, you can read Excel files. Also there is Eppy, that can manipulate IDF. Both of them works with lists. If you have a good naming convention in the IDF it's quite easy to loop through these lists and fill up your IDF objects with data from Excel.

Maybe I could use something else for the holes instead of IRTMaterial. Is that possible?

Wow, that is wery handy, I didn't know about that. Thanks rraustad. Anyway, in the dummy model (see EDIT part of original question) the problem does not come up during warmup. It occours, when solar heat gain, (or isnide temperatures) are starting to get high. I also tried it with FullExteriorAndInterior, this way the solar heat gain, I assume, falls to the bottom floor, and walls of the building, not the horizontal hole, thus there is no error. Unfortunately FullExteriorAndIInterior is not an option in my original modell, because of the non-convex zones. How could I bypass this problem?