1. Model DescriptionΒΆ

val-tab shows all the details for the used variables.

{table} Variables used for mathematical description :name: val-tab

symbols of variables

unit

definition

description

\( x_{{th}_{j,t}} \)

non -negative real

thermal energy fed into the grid

\( Cap_{j} \)

non -negative real

capacity

\( Cap_{{nom}_{j}} \)

non -negative real

normative capacity

\( x_{{el}_{j,t}} \)

non -negative real

electrical energy fed into the grid

\( P_{{el}_{max}} \)

non -negative real

maximum electrical power

\( x_{{load}_{hs,t}} \)

real

optimization variable depending on the load of heat storages, time-dependent

\( Cap_{hs} \)

non -negative real

capacity of heat storage

\( storelevel_{{hs}_{t}} \)

non -negative real

storage level of heat storage, time-dependent

\( ramp_{{j}_{chp,t}} \)

non -negative real

ramp function, chp (combined heat and power) and time-dependent

\( ramp_{{j}_{waste,t}} \)

non -negative real

ramp function, waste and time-dependent

\( coldstart_{j,t} \)

boolean

cold start, time-dependent

\( Activate_{j,t} \)

boolean

\( Activate_{{2}_{j,t}} \)

binary

\( Activate_{{3}_{j,t}} \)

binary

In param-tab, the parameters are mentioned and described.

{table} Parameters used for mathematical description :name: param-tab

symbols of parameters

unit

definition

description

\( demand_{{th}_{t}} \)

thermal demand, time-dependent

\( temp_{river} \)

temperature of river water

\( temp_{ww} \)

temperature of waste water

\( temp_{flow} \)

flow temperature

\( temp_{return} \)

return temperature

\( temp_{ambient} \)

ambient temperature

\( radiation \)

solar radiation

\( max_{demand} \)

maximum demand

\( potential_{j} \)

potential of the heat generator j

\( pow_{{cap}_{j}} \)

\( radiation_{t} \)

radiation, time-dependent

\( IK_{j} \)

\( OP_{{fix}_{j}} \)

\( n_{{el}_{j}} \)

electrical efficiency of heat generator j

\( elPrice_{jt} \)

electricity price for heat generator j , time-dependent

\( P_{{min,el}_{chp}} \)

minimum electrical power of chp

\( Q_{{min,th}_{chp}} \)

minimum thermal energy of chp

\( ratio_{{P,max}_{FW}} \)

ratio of maximum power for FW

\( ratio_{P,max} \)

ratio of maximum power

\( mc_{jt} \)

\( n_{{th}_{jt}} \)

thermal efficiency of heat generator j, time-dependent

\( hp_{{restrictionfactor}_{jt}} \)

restriction factor of heat pump of heat generator j, time-dependent

\( nom_{{p}_{th,j}} \)

\( min_{{p}_{th,j}} \)

\( x_{{th}_{cap,j}} \)

\( lt_{j} \)

\( ec_{j} \)

\( ir \)

\( \alpha_{j} \)

\( load_{{cap}_{hs}} \)

load capacity of heat storage

\( unload_{{cap}_{hs}} \)

unload capacity of heat storage

\( n_{hs} \)

efficiency of heat storage

\( loss_{hs} \)

losses of heat storage

\( IK_{hs} \)

IK of heat storage

\( cap_{hs} \)

capacity of heat storage

\( c_{{ramp}_{chp}} \)

\( c_{{ramp}_{waste}} \)

\( c_{{coldstart}_{j}} \)

\( \alpha_{hs} \)

\( rf_{j} \)

\( rf_{tot} \)

\( OP_{{var}_{j}} \)

\( temperature_{t} \)

time-dependent temperature

\( sale_{{electricityprice}_{jt}} \)

\( OP_{{fix}_{hs}} \)

\( mr_{j} \)

\( em_{j} \)

\( pco2 \)

\(CO_2\) price

\( cap_{{losse}_{hs}} \)

capacity losses of heat storages

\( n_{{th}_{nom,jt}} \)

thermal, normative efficiency of heat generator j, time-dependent

\( restricitionfactor_{th} \)

thermal restriction factor

\( min_{{out}_{factor,j}} \)

minimum output factor of heat generator j