Model Definition

For the modeling and optimization of an energy system, parameters for all system components must be given in the model generator using the enclosed .xlsx file (editable with Excel, LibreOffice, …). The .xlsx file is divided into nine input sheets. In the “energysystem” sheet, general parameters are defined for the time horizon to be examined, in the sheets “buses”, “sinks”, “sources”, “transformers”, “storages” and “links” corresponding components are defined. In the sheet “time series”, the performance of individual components can be stored. In the “weather data” sheet, the required weather data is stored. When completing the input file, it is recommended to enter the energy system step by step and to perform test runs in between, so that potential input errors are detected early and can be localized more easily. In addition to the explanation of the individual input sheets, an example energy system is built step by step in the following subchapters. The input file for this example is stored in the program folder “examples” and viewed on GitHub. The following units are used throughout:

  • capacity/performance in kW,

  • energy in kWh,

  • angles in degrees, and

  • costs in cost units (CU).

Cost units are any scalable quantity used to optimize the energy system, such as euros or grams of carbon dioxide emissions.

Energysystem

Within this sheet, the time horizon and the temporal resolution of the model is defined. The following parameters have to be entered:

  • start date: Start of the modelling time horizon. Format: “YYYY-MM-DD hh:mm:ss”;

  • end date: End date of the modelling time horizon. Format: “YYYY-MM-DD hh:mm:ss”; and

  • temporal resolution: For the modelling considered temporal resolution. Possible inputs: “a” (years), “d” (days), “h” (hours) “min” (minutes), “s” (seconds), “ms” (milliseconds).

  • timezone: By specifying the timezone, energy systems with correct time series (e.g. relevant for the correct balancing of the PV yield) can be modeled anywhere in the world. For this purpose, the pandas timezone string (e.g. Europe/Berlin) is inserted into the column. Then the weather data, which are available in the weather data sheet in UTC form, are corrected to the considered location.

  • periods: Number of periods within the time horizon (one year with hourly resolution equals 8760 periods).

  • cost limit in (CU): Value in order to set a limit for the whole energysystem, e.g. monetary costs. Set this field to “None” in order to ignore the limit. If you want to set a limit, you have to set specific values for each components seen below.

  • constraint cost limit in (CU): Value in order to set a limit for the whole energysystem, e.g. carbon dioxide emissions. Set this field to “None” in order to ignore the limit. If you want to set a limit, you have to set specific values for each components seen below.

  • minimum final energy reduction in (kWh): This value can be used to define how much final energy reduction must be achieved. Thus, the optimization algorithm is forced to save at least <your_value_here> kWh of final energy amount. Currently only insulation investments can be used to achieve reductions. The “constraint2” factor of the insulation measures is 1, since every kWh saved by insulation measures is fully included in the savings. This value is set in the algorithm and can currently not be changed by the user.

  • weather data lat: Latitude (WGS84) of the area under investigation. This value is used to import weather data from Open Energy Platform using feedinlib’s OpenFred.

  • weather data lon: Longitude (WGS84) of the area under investigation. This value is used to import weather data from Open Energy Platform using feedinlib’s OpenFred.

Exemplary input for the energy system

start date

end date

timezone

temporal resolution

periods

cost limit

constraint cost limit

minimum final energy reduction

weather data lat

weather data lon

(CU)

2012-01-01 00:00:00

2012-12-30 23:00:00

Europe/Berlin

h

8760

None

None

None

None

None

Competition Constraints

The spreadsheet “Competition Constraints” allows you to match two components against a predefined limit. For example, an area competition. If you do not want to use this spreadsheet, it simply remains empty. To use this worksheet, the following values must be filled in:

  • label: Unique designation of the competition constraint.

  • comment: Space for an individual comment.

  • component 1: First component that lays claim to the parameter which size set as the limit.

  • factor 1: Factor that defines how many units of the target unit component 1 needs to provide 1 kW of power.

  • component 2: Second component that lays claim to the parameter which size set as the limit.

  • factor 2: Factor that defines how many units of the target unit component 2 needs to provide 1 kW of power.

  • limit: Maximum size suitable for providing power (e.g. roof area for providing electricity and heat).

Exemplary input for the competition constraints sheet

label

comment

component 1

factor 1

component 2

factor 2

limit

unit/KW

unit/kW

unit

ID_competition

ID_photovoltaic_electricity_source

5.26

ID_solar_thermal_source

1.79

168

Buses

Within this sheet, the buses of the energy system are defined. The following parameters need to be entered:

  • label: Unique designation of the bus. The following format is recommended: “ID_energy sector_bus”.

  • comment: Space for an individual comment, e.g. an indication of which measure this component belongs to.

  • active: Specifies whether the bus shall be included to the model. 0 = inactive, 1 = active.

  • excess: Specifies whether a sink is to be generated, which consumes excess energy. 0 = no excess sink will be generated; 1 = excess sink will be generated.

  • shortage: Specifies whether to generate a shortage source that can compensate energy deficits or not. 0 = no shortage source will be generated; 1 = shortage source will be generated.

  • excess costs in (CU/kWh): Assigns a price per kWh to the release of energy to the excess sink. If the excess sink was deactivated, the fill character “0” is used.

  • shortage costs in (CU/kWh): Assigns a price per kWh to the purchase of energy from the shortage source. If the shortage source was deactivated, the fill character “0” is used.

  • excess constraint costs in (CU/kWh): Assigns a price per kWh to the release of energy to the excess sink referring to the constraint limit set in the “energysystem” sheet. If the excess sink was deactivated, the fill character “0” is used. If not considering constraints fill character “0” is used.

  • shortage constraint costs in (CU/kWh): Assigns a price per kWh to the purchase of energy from the shortage source referring to the constraint limit set in the “energysystem” sheet. If the shortage source was deactivated, the fill character “0” is used. If not considering constraints fill character “0” is used.

  • district heating conn.: This column allows you to specify whether the bus should be connected to the heating network. If not, select 0. If yes, either the nearest point of the heating network can be used as a connection (in this case the column must be filled with “dh-system”), or one of the street points from the “District Heating” sheet is used (in this case the column must be filled according to the following pattern: street-label-1 for the first node or street-label-2 for the second).

  • lat: This column must be filled if dh-system was specified in the “district heating conn.” column. In this case, this column must be filled with the latitude (WGS84).

  • lon: This column must be filled if dh-system was specified in the “district heating conn.” column. In this case, this column must be filled with the longitude (WGS84).

  • sector: This column is used to assign the shortages of the buses to the energy amount diagrams in the result processing. Possible entries: electricity, heat, cooling, central_electricity, central_heat, central_cooling and None for buses that cannot be assigned to any category.

Exemplary input for the buses sheet

label

comments

active

excess

shortage

excess costs

shortage costs

excess constraint costs

shortage constraint costs

district heating conn.

lat

lon

sector

(CU/kWh)

(CU/kWh)

(CU/kWh)

(CU/kWh)

ID_electricity_bus

1

0

1

0.000

0.300

0.00

474.00

0

0

0

electricity

ID_heat_bus

1

1

0

0.000

0.000

0.00

0.00

0

0

0

heat

ID_gas_bus

1

0

1

0.000

0.070

0.00

0.00

0

0

0

None

ID_cooling_bus

chiller

1

1

0

0.000

0.000

0.00

0.00

0

0

0

cooling

ID_pv_bus

1

1

0

-0.068

0.000

-56.00

0.00

0

0

0

electricity

ID_hp_electricity_bus

heat pumps

1

1

1

0.000

0.220

0.00

474.00

0

0

0

electricity

district_electricity_bus

delivering electr. to neighb. subsystems

0

0

0

0.000

0.000

0.00

0.00

0

0

0

central_electricity

district_heat_bus

delivering heat to neighb. subsystems

0

0

0

0.000

0.000

0.00

0.00

dh-system

50.000000

10.000000

central_heat

district_chp_electricity_bus

0

0

1

0.000

0.000

-375.00

0.00

0

0

0

central_electricity

district_gas_bus

0

0

1

0.000

0.070

0.00

0.00

0

0

0

None

Bus_Graph

Graph of the energy system, which is created by entering the example components. The non-active components are not included in the graph above.

District Heating

Within this sheet, the road network structure of the energy system is defined. The following parameters need to be entered:

  • label: Unique designation of the street section, e.g. the street section name.

  • comment: Space for an individual comment.

  • active: Specifies whether the street section shall be included to the model. 0 = inactive, 1 = active.

  • lat. 1st intersection: Latitude (WGS84) of the first point of the given street part.

  • lon. 1st intersection: Longitude (WGS84) of the first point of the given street part.

  • lat. 2nd intersection: Latitude (WGS84) of the second point of the given street part.

  • lon. 2nd intersection: Longitude (WGS84) of the second point of the given street part.

Exemplary input for the district heating sheet

label

comment

active

lat. 1st intersection

lon. 1st intersection

lat. 2nd intersection

lon. 2nd intersection

street1

1

50.000000

10.000000

55.000000

11.000000

Sinks

Within this sheet, the sinks of the energy system are defined. The following parameters need to be entered:

  • label: Unique designation of the sink. The following format is recommended: “ID_energy sector_sink”.

  • comment: Space for an individual comment, e.g. an indication of which measure this component belongs to.

  • active: Specifies whether the sink shall be included to the model. 0 = inactive, 1 = active.

  • fixed: Indicates whether it is a fixed sink or not. 0 = not fixed; 1 = fixed.

  • input: Specifies the bus from which the input to the sink comes from.

  • load profile: Specifies the basis onto which the load profile of the sink is to be created. If the Richardson tool is to be used, “richardson” has to be inserted. For standard load profiles, its acronym is used. If a time series is used, “timeseries” must be entered and must be provided in the Time series sheet. If the sink is not fixed, the fill character “x” has to be used.

  • nominal value in (kW): Nominal performance of the sink. Required when “timeseries” has been entered into the “load profile”. When SLP or Richardson is used, use the fill character “0” here.

  • annual demand in (kWh/a): Annual energy demand of the sink. Required when using the Richardson Tool or standard load profiles. When using time series, the fill character “0” is used.

  • occupants [RICHARDSON]: Number of occupants living in the respective building. Only required when using the Richardson tool, use fill character “0” for other load profiles.

  • building class [HEAT SLP ONLY]: BDEW building classes that coincide with the building locations are explained here.

  • wind class [HEAT SLP ONLY]: Wind classification for building location (0=not windy, 1=windy).

  • sector: This column is used to assign the sinks’ energy amounts to the energy amount diagrams in the result processing. Possible entries: electricity, heat, cooling.

Exemplary input for the sinks sheet

label

comment

active

fixed

input

load profile

nominal value

annual demand

occupants

building class

wind class

sector

(kW)

(kWh/a)

(richardson)

(heat slp)

(heat slp)

ID_electricity_sink

H0 standard load profile sink

1

1

ID_electricity_bus

h0

0

5000.0

0

0

0

electricity

ID_heat_sink

EFH standard load profile sink

1

1

ID_heat_bus

efh

0

30000.0

0

3

0

heat

ID_cooling_sink

fixed timeseries cooling demand

0

1

ID_cooling_bus

timeseries

1

0

0

0

0

cooling

Sink_Graph

Graph of the energy system, which is created by entering the example components. The non-active components are not included in the graph above.

Sources

Within this sheet, the sources of the energy system are defined. Technology specific data (see 2nd line), must be filled in only if the respective technology is selected otherwise use 0. The following parameters have to be entered:

  • label: Unique designation of the source. The following format is recommended: “ID_energy sector_source”.

  • comment: Space for an individual comment, e.g. an indication of which measure this component belongs to.

  • active: Specifies whether the source shall be included to the model. 0 = inactive, 1 = active.

  • fixed: Indicates whether it is a fixed source or not. 0 = not fixed; 1 = fixed.

  • output: Specifies which bus the output of the source is connected to.

  • inout: Specifies which bus the input of the source is connected to (only needed for solar heat).

  • technology: Technology type of source. Input options: “photovoltaic”, “windpower”, “timeseries”, “other”, “solar_thermal_flat_plate”, “concentrated_solar_power”. Time series are automatically generated for photovoltaic systems and wind turbines. If “timeseries” is selected, a time series must be provided in the Time series sheet.

  • sector: This column is used to differentiate between an electricity, heat and cooling timeseries source for the result processing’s energy amount collection. Possible entries: electricity, heat, cooling, central_electricity, central_heat, central_cooling.

Costs

  • existing capacity in (kW): Existing capacity of the source before possible investments.

  • min. investment capacity in (kW): Minimum capacity to be installed in case of an investment.

  • max. investment capacity in (kW): Maximum capacity that can be added in the case of an investment. If no investment is possible, enter the value “0” here.

  • variable costs in (CU/kWh): Defines the variable costs incurred for a kWh of energy drawn from the source.

  • variable constraint costs in (CU/kWh): Defines the variable costs incurred for a kWh of energy drawn from the source referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • periodical costs in (CU/(kW a)): Costs incurred per kW for investments within the time horizon. Periodical costs only apply for newly invested capacities but not for existing capacities.

  • periodical constraint costs in (CU/(kW a)): Costs incurred per kW for investments within the time horizon referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • Non-Convex Investment: Specifies whether the investment capacity should be defined as a mixed-integer variable, i.e. whether the model can decide whether NOTHING OR THE INVESTMENT should be implemented. Explained here.

  • Fix Investment Costs in (CU/a): Fixed costs of non-convex investments (in addition to the periodic costs).

  • Fix Investment Constraint Costs in (CU/a): Fixed constraint costs of non-convex investments (in addition to the periodic costs)

Wind

The following parameters need to be set for wind sources.

The wind speed timeseries entered in the sheet “weather data” (measured at 10 m height) will get converted into wind speeds at specified hub height. With the specified turbine model an energy timeseries will then be calculated.

  • Turbine Model: Reference wind turbine model. Possible turbine types are listed in the windpowerlib’s database. Write the value of the column “turbine_type” of the .csv in your spreadsheet.

  • Hub Height: Hub height of the wind turbine. Which hub heights are possible for the selected reference turbine can be viewed in the windpowerlib’s database too.

PV

The following parameters need to be set for PV sources.

  • Modul Model: Module name, according to the database used (see PVLIB database). Possible Modul Models are presented here.

  • Inverter Model: Inverter name, according to the database used. Possible Inverter Models are presented here.

  • Azimuth: Specifies the orientation of the PV module in degrees. Values between 0 and 360 are permissible (0 = north, 90 = east, 180 = south, 270 = west). Use fill character “0” for other technologies.

  • Surface Tilt: Specifies the inclination of the module in degrees (0 = flat). Use fill character “0” for other technologies.

  • Albedo: Specifies the albedo value of the reflecting floor surface. Only required for photovoltaic sources, use fill character “0” for other technologies.

  • Altitude: Height (above mean sea level) in meters of the photovoltaic module. Only required for photovoltaic sources, use fill character “0” for other technologies.

  • Latitude: Geographic latitude (decimal number) of the photovoltaic module. Only required for photovoltaic sources, use fill character “0” for other technologies.

  • Longitude: Geographic longitude (decimal number) of the photovoltaic module. Only required for photovoltaic sources, use fill character “0” for other technologies.

Concentrated Solar Power

The following parameters need to be set for concentrated solar power sources.

  • Azimuth: Specifies the orientation of the PV module in degrees. Values between 0 and 360 are permissible (0 = north, 90 = east, 180 = south, 270 = west). Use fill character “0” for other technologies.

  • Surface Tilt: Specifies the inclination of the module in degrees (0 = flat). Use fill character “0” for other technologies.

  • ETA 0: Optical efficiency of the collector. Use fill character “0” for other technologies.

  • A1: Collector specific linear heat loss coefficient. Use fill character “0” for other technologies.

  • A2: Collector specific quadratic heat loss coefficient. Use fill character “0” for other technologies.

  • C1: Collector specific thermal loss parameter. Only required for concentrated solar power source, use fill character “0” for other technologies.

  • C2: Collector specific thermal loss parameter. Only required for concentrated solar power source, use fill character “0” for other technologies.

  • Temperature Inlet in (°C): Inlet temperature of the solar heat collector module. Use fill character “0” for other technologies.

  • Temperature Difference in (°C): Temperature Difference between in- and outlet temperature of the solar heat collector module. Use fill character “0” for other technologies.

  • Cleanliness: Cleanliness of a parabolic through collector. Only required for Concentrated Solar Power source, use fill character “0” for other technologies.

  • Electric Consumption: Electric consumption of the collector system. Example: If value is set to 0,05, the electric consumption is 5 % of the energy output. Use fill character “0” for other technologies.

  • Peripheral Losses: Heat loss coefficient for losses in the collector’s peripheral system. Use fill character “0” for other technologies.

Exemplary values for concentrated_solar_power technology:

Exemplary values for concentrated_solar_power technology (The parameters refer to Janotte, N; et al)

Cleanliness

ETA 0

A1

A2

C1

C2

solar heat

solar heat

solar heat

solar heat

solar heat

solar heat

0.9

0.816

-0.00159

0.0000977

0.0622

0.00023

Solar Thermal Flatplate

The following parameters need to be set for solar thermal flatplate sources.

  • Azimuth: Specifies the orientation of the PV module in degrees. Values between 0 and 360 are permissible (0 = north, 90 = east, 180 = south, 270 = west). Use fill character “0” for other technologies.

  • Surface Tilt: Specifies the inclination of the module in degrees (0 = flat). Use fill character “0” for other technologies.

  • ETA 0: Optical efficiency of the collector. Use fill character “0” for other technologies.

  • A1: Collector specific linear heat loss coefficient. Use fill character “0” for other technologies.

  • A2: Collector specific quadratic heat loss coefficient. Use fill character “0” for other technologies.

  • Temperature Inlet in (°C): Inlet temperature of the solar heat collector module. Use fill character “0” for other technologies.

  • Temperature Difference in (°C): Temperature Difference between in- and outlet temperature of the solar heat collector module. Use fill character “0” for other technologies.

  • Electric Consumption: Electric consumption of the collector system. Example: If value is set to 0,05, the electric consumption is 5 % of the energy output. Use fill character “0” for other technologies.

  • Peripheral Losses: Heat loss coefficient for losses in the collector’s peripheral system. Use fill character “0” for other technologies.

  • Conversion Factor in m²/kW: The factor is explained here.

Timeseries

If you have chosen the technology “timeseries” (in the technology column), you have to include a timeseries in the Time series sheet or use default one.

Commodity

If you have chosen the technology “other” (in the technology column), a commodity source with maximum investable capacity but completely variable time series becomes part of the energy system. The solver can thus design a completely linear source and use it to cover the demand when required.

Exemplary input for the sources sheet

label

comment

active

fixed

technology

output

input

existing capacity

min. investment capacity

max. investment capapcity

non-convex investment

fix investment costs

variable costs

periodical costs

variable constraint costs

periodical constraint costs

Turbine Model

Hub Height

technology database

inverter database

Modul Model

Inverter Model

Albedo

Altitude

Azimuth

Surface Tilt

Latitude

Longitude

ETA 0

A1

A2

C1

C2

Temperature Inlet

Temperature Difference

Conversion Factor

Peripheral Losses

Electric Consumption

Cleanliness

sector

solar heat

(kW)

(kW)

(kW)

(CU/a)

(CU/kWh)

(CU/(kW a))

(CU/kWh)

(CU/(kW a))

windpower

windpower

PV

PV

PV

PV

PV

(m)| PV

(°)

(°)

(°)

(°)

solar heat

solar heat

solar heat

solar heat

solar heat

(°C) | solar heat

(°C)|solar heat

(sqm/kW) | solar heat

solar heat

solar heat

solar heat

ID_photovoltaic_electricity_source

1

1

photovoltaic

ID_pv_bus

None

0

0

20

0

0

0

90

56

0

0

0

SandiaMod

sandiainverter

Panasonic_VBHN235SA06B__2013_

ABB__MICRO_0_25_I_OUTD_US_240__240V_

0.18

60

180

35

52.13

7.36

0

0

0

0

0

0

0

0

0

0

0

electricity

ID_solar_thermal_source

1

1

solar_thermal_flat_plate

ID_heat_bus

ID_electricity_bus

0

0

20

0

0

0

40

25

0

0

0

0

0

0

0

0

0

20

10

52.13

7.36

0.719

1.063

0.005

0

0

40

15

1.79

0.05

0.06

0

heat

wind_turbine

0

1

windpower

electricity_bus

None

0

0

30

0

0

0

100

9

0

E-126/4200

135

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

electricity

Source_Graph

Graph of the energy system, which is created by entering the example components of sources sheet. The non-active components are not included in the graph above.

Transformers

Within this sheet, the transformers of the energy system are defined.

The following parameters have to be entered:

  • label: Unique designation of the transformer. The following format is recommended: “ID_energy sector_transformer”.

  • comment: Space for an individual comment, e.g. an indication of which measure this component belongs to.

  • active: Specifies whether the transformer shall be included to the model. 0 = inactive, 1 = active.

  • transformer type: Indicates what kind of transformer it is. Possible entries: “GenericTransformer” for linear transformers with constant efficiencies; “GenericTwoInputTransformer” for transformers with two inputs and constant efficiencies (e. g. Pumping units with water and electricity intake); “GenericCHP” for transformers with varying efficiencies; “CompressionHeatTransformer”; “AbsorptionHeatTransformer”.

  • mode: Specifies, if a compression or absorption heat transformer is working as “chiller” or “heat_pump”. Only required if “transformer type” is set to “CompressionHeatTransformer” or “AbsorptionHeatTransformer”. Otherwise has to be set to “None”, “none”, “0”.

  • input: Specifies the bus from which the input to the transformer comes from.

  • input2: Specifies the bus from which the input2 to the transformer comes from. Only required if “transformer type” is set to “GenericTwoInputTransformer”. If there is no second input, the fill character “0” must be entered here.

  • output: Specifies bus to which the output of the transformer is forwarded to. For CHP Transformers it should be the electric output.

  • output2: Specifies the bus to which the output of the transformer is forwarded to, if there are several outputs. If there is no second output, the fill character “0” must be entered here.

  • input2 / input: Specifies the ratio of input2 to input (e. g. kWh/m³). Only required if “transformer type” is set to “GenericTwoInputTransformer”. If there is no second input, the fill character “0” must be entered here.

  • sector: This column is used to differentiate the transformer types for the result processing’s energy amount collection. Possible entries: electricity, heat, cooling, central_electricity, central_heat, central_cooling, electric_heating.

  • technology: The technology column represents the category for collecting the energy amounts for the energy amount diagrams. Attention: If at sector central_… is used, a leading “central_” will be added to the selected technology in the balancing.

Costs

  • variable input costs in (CU/kWh): Variable costs incurred per kWh of input energy supplied.

  • variable input costs 2 in (CU/kWh): Variable costs incurred per kWh of input2 energy supplied.

  • variable output costs in (CU/kWh): Variable costs incurred per kWh of output energy supplied.

  • variable output costs 2 in (CU/kWh): Variable costs incurred per kWh of output 2 energy supplied.

  • variable input constraint costs in (CU/kWh): Variable constraint costs incurred per kWh of input energy supplied referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • variable input constraint costs 2 in (CU/kWh): Variable constraint costs incurred per kWh of input2 energy supplied referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • variable output constraint costs in (CU/kWh): Variable constraint costs incurred per kWh of output energy supplied referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • variable output constraint costs 2 in (CU/kWh): Variable constraint costs incurred per kWh of output 2 energy supplied referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • existing capacity in (kW): Already installed capacity of the transformer.

  • min investment capacity in (kW): Minimum transformer capacity to be installed.

  • max investment capacity in (kW): Maximum installable transformer capacity regarding the output of the transformer, in addition to previously installed capacity, if existing.

  • periodical costs in (CU/a): Costs incurred per kW for investments within the time horizon. Periodical costs only apply for newly invested capacities but not for existing capacities.

  • periodical constraint costs in (CU/(kW a)): Constraint costs incurred per kW for investments within the time horizon. If not considering constraints fill character “0” is used.

  • Non-Convex Investment: Specifies whether the investment capacity should be defined as a mixed-integer variable, i.e. whether the model can decide whether NOTHING OR THE INVESTMENT should be implemented. Explained here.

  • Fix Investment Costs in (CU/a): Fixed costs of non-convex investments (in addition to the periodic costs).

  • Fix Investment Constraint Costs in (CU/a): Fixed constraint costs of non-convex investments (in addition to the periodic costs).

Generic Transformer

  • efficiency: Specifies the efficiency of the first output. Values between 0 and 1 are allowed entries.

  • efficiency2: Specifies the efficiency of the second output, if there is one. Values between 0 and 1 are entered. If there is no second output, the fill character “0” must be entered here.

Compression Heat Transformer

The following parameters are only required, if “transformer type” is set to “CompressionHeatTransformer”:

  • heat source: Specifies the heat source. Possible heat sources are “GroundWater”, “Ground”, “Air”, “Air-to-Air” (which represents an AAHP) and “Water” possible.

  • temperature high in (°C): Temperature of the high temperature heat reservoir. Only required if “mode” is set to “heat_pump”.

  • temperature low in (°C): Cooling temperature needed for cooling demand. Only required if “mode” is set to “chiller”.

  • quality grade: To determine the COP of a real machine a scale-down factor (the quality grade) is applied on the Carnot efficiency (see oemof.thermal).

  • area in (sqm): Open spaces for ground-coupled compression heat transformers (GC-CHT).

  • length of the geoth. probe in (m): Length of the vertical heat exchanger, only for GC-CHT.

  • heat extraction in (kW/(m*a)): Heat extraction for the heat exchanger referring to the location, only for GC-CHT.

  • min. borehole area in (sqm): Limited space due to the regeneation of the ground source, only for GC-CHT.

  • temp threshold icing: Temperature below which icing occurs (see oemof.thermal). Only required if “mode” is set to “heat_pump”.

  • factor icing: Factor to which the COP is reduced caused by icing (e.g. 0.8 if you have a reduction of 20%). (see oemof.thermal). Only required if “mode” is set to “heat_pump”.

Absorption Heat Transformer

The following parameters are only required, if “transformer type” is set to “AbsorptionHeatTransformer”:

  • name: Defines the way of calculating the efficiency of the absorption heat transformer. Possible inputs are: “Rotartica”, “Safarik”, “Broad_01”, “Broad_02”, and “Kuehn”. “Broad_02” refers to a double-effect absorption chiller model, whereas the other keys refer to single-effect absorption chiller models.

  • temperature high in (°C): Temperature of the heat source, that drives the absorption heat transformer.

  • temperature low in (°C): Output temperature which is needed for the cooling demand.

  • electrical input conversion factor: Specifies the relation of electricity consumption to energy input. Example: A value of 0,05 means, that the system comsumes 5 % of the input energy as electric energy.

  • recooling temperature difference in (°C): Defines the temperature difference between temperature source for recooling and recooling cycle.

  • heat capacity of source: Defines the heat capacity of the connected heat source e.g. extracted waste heat.

GenericCHP

Warning

Currently the GenericCHP component can only be used for the purpose of simulation. The solver is not able to dimension the components capacity. Since there is no investment decision no periodical costs apply.

  • min. share of flue gas loss: Percentage flue gas losses of the operating point with maximum heat extraction.

  • max. share of flue gas loss: Percentage flue gas losses of the operating point with minimum heat extraction.

  • min. electric power in (kW): Minimum electrical power supply without heat extraction (district heating).

  • max. electric power in (kW): Maximum electrical power supply without heat extraction (district heating).

  • min. electric efficiency: Specifies the minimum electric efficiency without heat extraction (district heating). Values between 0 and 1 are allowed entries.

  • max. electric efficiency: Specifies the minimum electric efficiency without heat extraction (district heating). Values between 0 and 1 are allowed entries.

  • minimal thermal output power in (kW): Heat output taken from the exhaust gas via a condenser even in purely electric operation.

  • electric power loss index: Reduction of the electrical power by “electric power loss index * extracted thermal power”.

  • back pressure: Defines rather the end pressure of “Turbine CHP” is higher than ambient pressure (input value has to be “1”) or not (input value has to be “0”). For “Motoric CHP” it has to be “0”.

Exemplary input for the transformers sheet

label

comment

active

transformer type

mode

input

input2

output

output2

input2 / input

efficiency

efficiency2

existing capacity

min. investment capacity

max. investment capacity

non-convex investment

fix investment costs

variable input costs

variable input costs 2

variable output costs

variable output costs 2

periodical costs

variable input constraint costs

variable input constraint costs 2

variable output constraint costs

variable output constraint costs 2

periodical constraint costs

heat source

temperature high

temperature low

quality grade

area

length of the geoth. probe

heat extraction

min. borehole area

temp. threshold icing

factor icing

name

electrical input conversion factor

recooling temperature difference

min. share of flue gas loss

max. share of flue gas loss

min. electric power

max. electric power

min. electric efficiency

max. electric efficiency

minimal thermal output power

elec. power loss index

back pressure

sector

technology

(kW)

(kW)

(kW)

(CU/a)

(CU/kWh)

(CU/kWh)

(CU/kWh)

(CU/kWh)

(CU/(kW a))

(CU/kWh)

(CU/kWh)

(CU/kWh)

(CU/kWh)

(CU/(kW a))

(°C)

(°C)

(m²)

(m)

(kW/(m*a))

(m²)

(°C)

(°C)

(kW)

(kW)

(kW)

ID_gasheating_transformer

1

GenericTransformer

0

ID_gas_bus

0

ID_heat_bus

None

0

0.85

0

10

0

20

0

0

0

0

0

0

70

0

0

200

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

heat

natural_gasheating

ID_TwoInput_transformer

high pressure pump

0

GenericTwoInputTransformer

None

ID_water_intake_bus

ID_electricity_intake_bus

ID_water_output_bus

None

0.84

0.88

0

0

0

4000

0

0

0

0

0

0

6.600

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

None

None

ID_GCHP_transformer

ground-coupled heat pump

1

CompressionHeatTransformer

heat_pump

ID_hp_electricity_bus

0

ID_heat_bus

None

0

1

0

0

0

20

0

0

0

0

0

0

115.57

0

0

0

0

0

Ground

60

0

0.6

1000

100

0.05

100

3

0.8

0

0

0

0

0

0

0

0

0

0

0

0

heat

GCHP

ID_ASCH_transformer

air source chiller

1

CompressionHeatTransformer

chiller

ID_hp_electricity_bus

0

ID_cooling_bus

None

0

1

0

0

0

20

0

0

0

0

0

0

100

0

0

0

0

0

Air

0

-10

0.4

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

cooling

ASCH

ID_AbsCH_transformer

absorption chiller

1

AbsorptionHeatTransformer

chiller

ID_hp_electricity_bus

0

ID_cooling_bus

None

0

1

0

0

0

20

0

0

0

0

0

0

100

0

0

0

0

0

0

85

10

0

0

0

0

0

0

0

Kuehn

0.05

6

0

0

0

0

0

0

0

0

0

cooling

AbsCH

ID_ASHP_transformer

air source heat pump

1

CompressionHeatTransformer

heat_pump

ID_hp_electricity_bus

0

ID_heat_bus

None

0

1

0

0

0

20

0

0

0

0

0

0

112.78

0

0

0

0

0

Air

60

0

0.4

0

0

0

0

3

0.8

0

0

0

0

0

0

0

0

0

0

0

0

heat

ASHP

ID_chp_transformer

0

GenericTransformer

0

district_gas_bus

0

district_chp_electricity_bus

district_heat_bus

0

0.35

0.55

0

0

20

0

0

0

0

0

0

50

130

0

375

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

heat

natural_gas_CHP

Transformer_Graph

Graph of the energy system, which is created by entering the example components. The non-active components are not included in the graph above.

Storages

Within this sheet, the storages of the energy system are defined. The following parameters have to be entered:

  • label: Unique designation of the storage. The following format is recommended: “ID_energy sector_storage”.

  • comment: Space for an individual comment, e.g. an indication of which measure this component belongs to.

  • active: Specifies whether the storage shall be included to the model. 0 = inactive, 1 = active.

  • storage type: Defines whether the storage is a “Generic” or a “Stratified” sorage. These two inputs are possible.

  • bus: Specifies which bus the storage is connected to.

  • input/capacity ratio (invest): Indicates the performance with which the storage can be charged (see also here).

  • output/capacity ratio (invest): Indicates the performance with which the storage can be discharged (see also here).

  • efficiency inflow: Specifies the charging efficiency.

  • efficiency outflow: Specifies the discharging efficiency.

  • initial capacity: Specifies how far the storage is loaded at time 0 of the simulation. Value must be between 0 and 1. The initial capacity value must be equal or higher than the ‘capacity min’ value.

  • capacity min: Specifies the minimum amount of storage that must be loaded at any given time. Value must be between 0 and 1.

  • capacity max: Specifies the maximum amount of storage that can be loaded at any given time. Value must be between 0 and 1.

  • sector: This column is used to differentiate between an electricity, heat and cooling storages for the result processing’s energy amount collection. Possible entries: electricity, heat, cooling, central_electricity, central_heat, central_cooling.

Costs

  • existing capacity in (kW): Previously installed capacity of the storage.

  • min. investment capacity in (kW): Minimum storage capacity to be installed.

  • max. investment capacity in (kW): Maximum in addition to existing capacity, installable storage capacity.

  • Non-Convex Investment: Specifies whether the investment capacity should be defined as a mixed-integer variable, i.e. whether the model can decide whether NOTHING OR THE INVESTMENT should be implemented. Explained here.

  • Fix Investment Costs in (CU/a): Fixed costs of non-convex investments (in addition to the periodic costs)

  • Fix Investment Constraint Costs in (CU/a): Fixed constraint costs of non-convex investments (in addition to the periodic costs)

  • variable input costs: Indicates how many costs arise for charging with one kWh.

  • variable output costs: Indicates how many costs arise for charging with one kWh.

  • periodical costs in (CU/a): Costs incurred per kW for investments within the time horizon. Periodical costs only apply for newly invested capacities but not for existing capacities.

  • variable input constraint costs: Indicates how many costs arise for charging with one kWh referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • variable output constraint costs: Indicates how many costs arise for charging with one kWh referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

  • periodical constraint costs in (CU/a): Costs incurred per kW for investments within the time horizon referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

Generic Storage

  • capacity loss (Generic only): Indicates the percentage storage loss per time unit. Only required, if the “storage type” is set to “Generic”.

Stratified Storage

  • diameter in (m) | (Stratified Storage): Defines the diameter of a stratified thermal storage, which is necessary for the calculation of thermal losses.

  • temperature high in (°C) | (Stratified Storage): Outlet temperature of the stratified thermal storage.

  • temperature low in (°C) | (Stratified Storage): Inlet temperature of the stratified thermal storage.

  • U value in (W/(sqm*K)) | (Stratified Storage): Thermal transmittance coefficient

Exemplary input for the storages sheet

label

comment

active

storage type

bus

input/capacity ratio

output/capacity ratio

efficiency inflow

efficiency outflow

initial capacity

capacity min

capacity max

existing capacity

min. investment capacity

max. investment capacity

non-convex investment

fix investment costs

variable input costs

variable output costs

periodical costs

variable input constraint costs

variable output constraint costs

periodical constraint costs

capacity loss

diameter

temperature high

temperature low

U value

sector

(invest)

(invest)

(kWh)

(kWh)

(kWh)

(CU/a)

(CU/kWh)

(CU/kWh)

(CU/(kWh a))

(CU/kWh)

(CU/kWh)

(CU/(kWh a))

Generic Storage

(m) | Stratified Storage

(°C) | Stratified Storage

Stratified Storage

(W/(m²*K)) | Stratified Storage

ID_battery_storage

1

Generic

ID_electricity_bus

0.17

0.17

1

0.98

0

0.1

1

0

0

100

0

0

0

0

70

0

0

400

0

0

0

0

0

electricity

ID_thermal_storage

1

Generic

ID_heat_bus

0.17

0.17

1

0.98

0

0.1

0.9

0

0

100

0

0

0

20

35

0

0

100

0

0

0

0

0

heat

ID_stratified_thermal_storage

0

Stratified

ID_heat_bus

0.2

0.2

1

0.98

0

0.05

0.95

0

0

100

0

0

0

20

35

0

0

100

0

0.8

60

40

0.04

heat

district_battery_storage

0

Generic

district_electricity_bus

0.17

0.17

1

0.98

0

0.1

1

0

0

1000

0

0

0

0

10

0

0

10

0

0

0

0

0

central_electricity

Transformer_Graph

Graph of the energy system, which is created after entering the example components. The non-active components are not included in the graph above.

Insulation

Within this sheet, the energy system insulation options are defined. The following parameters have to be entered:

  • label: Unique designation of the insulation. The following format is recommended: “ID_sink_label_insulation_type”

  • comment: Space for an individual comment, e.g. an indication of which measure this component belongs to.

  • active: Specifies whether the insulation shall be included to the model. 0 = inactive, 1 = active.

  • existing: Existing represents a boolean decision (0=no, 1=yes). If a 1 is filled in here, the insulation measure is completely implemented without incurring any costs.

  • sink: Sink influenced by the insulation.

  • temperature indoor in (°C): Definition of the living space temperature.

  • heat limit temperature in (°C): Temperature from which the heating is switched on.

  • U-value old in (W/(m2 *K)): U-value before insulation.

  • U-value new in (W/(m2 *K)): U-value after insulation.

  • area in (m2): Area that can be considered for isolation.

  • periodical costs in (CU/(m2 *a)): Costs incurred per m2 for investments within the time horizon.

  • periodical constraint costs in (CU/(m2 *a)): Costs incurred per m2 for investments within the time horizon referring to the constraint limit set in the “energysystem” sheet. If not considering constraints fill character “0” is used.

Time Series

Within this sheet, time series of components of which no automatically created time series exist, are stored. More specifically, these are sinks to which the property “load profile” have been assigned as “timeseries” and sources with the “technology” property “timeseries”. The following parameters have to be entered:

  • timestamp: Points in time to which the stored time series are related. Should be within the time horizon defined in the sheet “timesystem”.

  • timeseries: Time series of a sink or a source which has been assigned the property “timeseries” under the attribute “load profile” or “technology. Time series contain a value between 0 and 1 for each point in time, which indicates the proportion of installed capacity accounted for by the capacity produced at that point in time. In the header line, the name must rather be entered in the format “componentID.fix” if the component enters the power system as a fixed component or it requires two columns in the format “componentID.min” and “componentID.max” if it is an unfixed component. The columns “componentID.min/.max” define the range that the solver can use for its optimisation.

Exemplary input for time series sheet

timestamp

residential_electricity_demand.actual_value

fixed_timeseries_electricty_source.fix

unfixed_timeseries_electricty_source.min

unfixed_timeseries_electricty_source.max

fixed_timeseries_electricity_sink.fix

unfixed_timeseries_electricity_sink.min

unfixed_timeseries_electricity_sink.max

fixed_timeseries_cooling_demand_sink.fix

2012-01-01 00:00:00

0.559061982

0.000000

0.000000

1.000000

0.000000

0.000000

1.000000

100

2012-01-01 01:00:00

0.533606486

0.041667

0.000000

0.500000

0.041667

0.000000

0.500000

100

2012-01-01 02:00:00

0.506058757

0.083333

0.000000

0.333333

0.083333

0.000000

0.333333

100

2012-01-01 03:00:00

0.504140877

0.125000

0.000000

0.250000

0.125000

0.000000

0.250000

100

2012-01-01 04:00:00

0.507104873

0.166667

0.000000

0.200000

0.166667

0.000000

0.200000

100

2012-01-01 05:00:00

0.511376515

0.208333

0.000000

0.166667

0.208333

0.000000

0.166667

100

2012-01-01 06:00:00

0.541801064

0.250000

0.000000

0.142857

0.250000

0.000000

0.142857

100

2012-01-01 07:00:00

0.569261616

0.291667

0.000000

0.125000

0.291667

0.000000

0.125000

100

2012-01-01 08:00:00

0.602998867

0.333333

0.000000

0.111111

0.333333

0.000000

0.111111

100

2012-01-01 09:00:00

0.629064598

0.375000

0.000000

0.100000

0.375000

0.000000

0.100000

100

Weather Data

If electrical load profiles are simulated with the Richardson tool, heating load profiles with the demandlib or photovoltaic systems with the feedinlib, weather data must be stored here. The weather data time system should be in conformity with the model’s time system, defined in the sheet “timesystem”.

  • timestamp: Points in time to which the stored weather data are related.

  • dhi: Diffuse horizontal irradiance in W/m2.

  • dni: Direct normal irradiance in W/m2.

  • ghi: Global horizontal irradiance in W/m2.

  • pressure: Air pressure in Pa.

  • temperature: Air temperature in °C.

  • windspeed: Wind speed, measured at 10 m height, in unit m/s.

  • z0: Roughness length of the environment in units m.

  • ground_temp: Constant ground temperature at 100 m depth.

  • water_temp: Varying water temperature of a river depending on the air temperature.

  • groundwater_temp: Constant temperatur of the ground water at 6 - 10 m depth in North Rhine-Westphalia.

Exemplary input for weather data

timestamp

dhi

dirhi

pressure

temperature

windspeed

z0

ground_temp

water_temp

groundwater_temp

2012-01-01 00:00:00

0.00

0.00

98405.70

10.33

7.2

0.15

13.7

14.62

13.06

2012-01-01 01:00:00

0.00

0.00

98405.70

10.33

7.8

0.15

13.7

14.62

13.06

2012-01-01 02:00:00

0.00

0.00

98405.70

10.48

7.7

0.15

13.7

14.71

13.06

2012-01-01 03:00:00

0.00

0.00

98405.70

10.55

7.7

0.15

13.7

14.75

13.06

2012-01-01 04:00:00

0.00

0.00

98405.70

10.93

7.8

0.15

13.7

14.99

13.06

2012-01-01 05:00:00

0.00

0.00

98405.70

10.90

8.5

0.15

13.7

14.97

13.06

2012-01-01 06:00:00

0.00

0.00

98405.70

10.88

8.5

0.15

13.7

14.96

13.06

2012-01-01 07:00:00

0.00

0.00

98405.70

11.22

7.9

0.15

13.7

15.17

13.06

2012-01-01 08:00:00

0.00

0.00

98405.70

11.68

8.7

0.15

13.7

15.46

13.06

2012-01-01 09:00:00

0.56

0.56

98405.70

11.87

8.6

0.15

13.7

15.57

13.06

2012-01-01 10:00:00

13.06

13.06

98405.70

11.65

8.0

0.15

13.7

15.44

13.06