Solar PV

The solar PV technology represents solar PV installations on rooftops and soon fassades. It is adjusted to the available roof potential in a given municipality.

For Switzerland, building-level estimates of annual rooftop photovoltaic potential are derived from a geospatial assessment published by the Swiss Federal Office of Energy (2023). Temporal PV production is represented by hourly generation profiles, which were simulated with the PV*SOL software (Valentin Software GmbH, 2025) for a set of representative locations across Switzerland and provided to DEM as time-series inputs. The irradiation data applied in PVSOL is based on a Typical Meterological Year.

Attribute	Description	Standard value	Unit	Data type
deployment	If set to ‘true’, the technology will be considered in the energy system model (this does not necessarily mean it will be used). Only relevant for optimisation.	True	—	bool
kWp_max	Kilowatt Peak: Maximum power output of PV system under standard test conditions (STC).	inf	kW	float
eta_overall	Overall conversion efficiency from solar radiation to electricity output at AC side.	0.15	—	float
co2_intensity	Carbon-dioxide intensity of technology output (annual average value).	0	kg CO2/kWh	float
lifetime	Expected lifetime of technology before replacement is required.	25	years	int
capex	CAPEX cost of technology per unit of capacity.	3000	CHF/kWp	float
maintenance_cost	OPEX cost of the technology.	6.45	CHF/kWp/year	float
interest_rate	Interest rate for computing levelised costs (if required).	0.025	—	float
potential_integration_factor	Used for scenario ‘pv_integration’. This factor specifies the fraction of additional solar VP potential to be implemented. The additional PV potential is based on suitable roof-space that is not yet covered with PV.	0.3	—	float
virtual_export_tariff	virtual export tarriff to prefer internal usage of the electricity	0	CHF/kWh	float
export_subsidy	subsidy to make export more likely (and prevent cycling of storages to curtail energy)	0	CHF/kWh	float
only_use_installed	If set to ‘true’, only the currently installed PV capacity can be used. No additional capacity will be built. Only relevant if Optimisation is activated	False	—	bool

The symbols and names of the flows are

v_e_pv_exp	Exported Electricity
v_e_pv	Outflow Electricity

References

Swiss Federal Office of Energy. (2023, January). Dokumentation Geodatenmodell – Solarenergie: Eignung Dächer (Sonnendach.ch); Solarenergie: Eignung Fassaden (Sonnenfassade.ch) (Technical report). Bern, Switzerland. Retrieved December 17, 2025, from https://www.bfe.admin.ch/bfe/en/home/supply/digitalization-and-geoinformation/geoinformation/geodata/solar-energy/suitability-of-roofs-for-use-of-solar-energy.html

Valentin Software GmbH. (2025). PVSOL [Software]. Berlin, Germany. Retrieved December 17, 2025, from https://valentin-software.com/en/products/pvsol/