East-west model with PV GIS data

[Richard L.]

 Hello everyone!

I am currently working on a model for a PV system with east-west orientation and am trying to import data from PVGIS. However, I am encountering a problem that I do not fully understand and would appreciate your help.

The error occurs when I run modelchain.run_model in my code and is: TypeError: Input must be a tuple of length 2, got DataFrame.

Unfortunately, I've reached a point where I don't know what to do and hope that someone of you can shed some light on this. I would greatly appreciate any assistance or advice on how to solve this problem.

Many thanks in advance and best regards,
Richard

PV Simulation # Location lat = row['Coord_lat'] lon = row['Coord_long'] alti = row['altitude'] location = Location(latitude=lat, longitude=lon, tz='Europe/Berlin', altitude=alti, name='EDID NR_Test') arrays = [ Array(FixedMount(surface_tilt=(30), surface_azimuth=(270)), name = "West Facing Arra", module_parameters=module, temperature_model_parameters=temperature_parameters, modules_per_string=m_string, strings=s_inverter), Array(FixedMount(surface_tilt=(30), surface_azimuth=(90)), name = "East Facing Arra", module_parameters=module, temperature_model_parameters=temperature_parameters, modules_per_string=m_string, strings=s_inverter) ] system = PVSystem(arrays=arrays, inverter_parameters=inverter) modelchain = ModelChain(system, location) # PV-GIS of east-west system # east orientation poa_data_east, meta_east, inputs_east = pvlib.iotools.get_pvgis_hourly( latitude=lat, longitude=lon, start=start_, end=end_, raddatabase="PVGIS-SARAH2", components=True, surface_tilt=(30), # fixed tilt angle surface_azimuth=90, # Fixed alignment for east orientation outputformat='json', usehorizon=True, userhorizon=None, pvcalculation=False, peakpower=None, pvtechchoice='crystSi', mountingplace='free', loss=0, trackingtype=0, optimal_surface_tilt=False, optimalangles=False, url='https://re.jrc.ec.europa.eu/api/v5_2/', map_variables=True, timeout=30) # west orientation poa_data_west, meta_west, inputs_west = pvlib.iotools.get_pvgis_hourly( latitude=lat, longitude=lon, start=start_, end=end_, raddatabase="PVGIS-SARAH2", components=True, surface_tilt=(30), # fixed tilt angle surface_azimuth=-90, # Fixed alignment for west orientation outputformat='json', usehorizon=True, userhorizon=None, pvcalculation=False, peakpower=None, pvtechchoice='crystSi', mountingplace='free', loss=0, trackingtype=0, optimal_surface_tilt=False, optimalangles=False, url='https://re.jrc.ec.europa.eu/api/v5_2/', map_variables=True, timeout=30) poa_data_2020 = poa_data_east.add(poa_data_west, fill_value=0) poa_data_2020['poa_diffuse'] = poa_data_2020['poa_sky_diffuse'] + poa_data_2020['poa_ground_diffuse'] poa_data_2020['poa_global'] = poa_data_2020['poa_diffuse'] + poa_data_2020['poa_direct'] poa_data_2020.index = pd.to_datetime(poa_data_2020.index) modelchain.run_model_from_poa(poa_data_2020) total_production = modelchain.results.ac.sum()

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[kevina...@gmail.com]

Hello Richard,

When using run_model_from_poa, a separate weather/irradiance dataframe must be supplied for each Array:

> If the ModelChain’s PVSystem has multiple arrays, data must be a list or tuple with the same length and order as the PVsystem’s Arrays. Each element of data provides the irradiance and weather for the corresponding array.

(from https://pvlib-python.readthedocs.io/en/stable/reference/generated/pvlib.modelchain.ModelChain.run_model_from_poa.html)

So since you're using two Arrays, you need to pass in a list of the two dataframes you got back from PVGIS.  I'm not sure what the current code is doing (adding the dataframes together) makes any sense anyway (~2000 W/m2 irradiance and twice the ambient temperature?).

Cheers,

Kevin

[Richard L.]

Hi Kevin

Many thanks for your reply. The hint has given me the right impulse and I think I have found my error. It seems to be working so far.

Thank you very much!

Richard

Here is the revised code snippet:

arrays = [ Array(FixedMount(surface_tilt=30, surface_azimuth=90), name="East Facing Array", module_parameters=module, temperature_model_parameters=temperature_parameters, modules_per_string=m_string, strings=s_inverter), Array(FixedMount(surface_tilt=30, surface_azimuth=270), name="West Facing Array", module_parameters=module, temperature_model_parameters=temperature_parameters, modules_per_string=m_string, strings=s_inverter) ] system = PVSystem(arrays=arrays, inverter_parameters=inverter) modelchain = ModelChain(system, location) # PV-GIS of east-west system # east orientation poa_data_east, meta_east, inputs_east = pvlib.iotools.get_pvgis_hourly( latitude=lat, longitude=lon, start=start_, end=end_, raddatabase="PVGIS-SARAH2", components=True, surface_tilt=(30), # fixed tilt angle surface_azimuth=90, # Fixed alignment for east orientation outputformat='json', usehorizon=True, userhorizon=None, pvcalculation=False, peakpower=None, pvtechchoice='crystSi', mountingplace='free', loss=0, trackingtype=0, optimal_surface_tilt=False, optimalangles=False, url='https://re.jrc.ec.europa.eu/api/v5_2/', map_variables=True, timeout=30) poa_data_east['poa_diffuse'] = poa_data_east['poa_sky_diffuse'] + poa_data_east['poa_ground_diffuse'] poa_data_east['poa_global'] = poa_data_east['poa_diffuse'] + poa_data_east['poa_direct'] # west orientation poa_data_west, meta_west, inputs_west = pvlib.iotools.get_pvgis_hourly( latitude=lat, longitude=lon, start=start_, end=end_, raddatabase="PVGIS-SARAH2", components=True, surface_tilt=(30), # fixed tilt angle surface_azimuth=-90, # Fixed alignment for west orientation outputformat='json', usehorizon=True, userhorizon=None, pvcalculation=False, peakpower=None, pvtechchoice='crystSi', mountingplace='free', loss=0, trackingtype=0, optimal_surface_tilt=False, optimalangles=False, url='https://re.jrc.ec.europa.eu/api/v5_2/', map_variables=True, timeout=30) poa_data_west['poa_diffuse'] = poa_data_west['poa_sky_diffuse'] + poa_data_west['poa_ground_diffuse'] poa_data_west['poa_global'] = poa_data_west['poa_diffuse'] + poa_data_west['poa_direct'] poa_data_east.index = pd.to_datetime(poa_data_east.index) poa_data_west.index = pd.to_datetime(poa_data_west.index) poa_data_2020 = (poa_data_east, poa_data_west) modelchain.run_model_from_poa(poa_data_2020)

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