diff --git a/scripts/build_cop_profiles/BaseCopApproximator.py b/scripts/build_cop_profiles/BaseCopApproximator.py index 89118284..10019b3d 100644 --- a/scripts/build_cop_profiles/BaseCopApproximator.py +++ b/scripts/build_cop_profiles/BaseCopApproximator.py @@ -14,6 +14,24 @@ class BaseCopApproximator(ABC): """ Abstract class for approximating the coefficient of performance (COP) of a heat pump. + + Attributes: + ---------- + forward_temperature_celsius : Union[xr.DataArray, np.array] + The forward temperature in Celsius. + source_inlet_temperature_celsius : Union[xr.DataArray, np.array] + The source inlet temperature in Celsius. + + Methods: + ------- + __init__(self, forward_temperature_celsius, source_inlet_temperature_celsius) + Initialize CopApproximator. + approximate_cop(self) + Approximate heat pump coefficient of performance (COP). + celsius_to_kelvin(t_celsius) + Convert temperature from Celsius to Kelvin. + logarithmic_mean(t_hot, t_cold) + Calculate the logarithmic mean temperature difference. """ def __init__( @@ -28,8 +46,8 @@ class BaseCopApproximator(ABC): ---------- forward_temperature_celsius : Union[xr.DataArray, np.array] The forward temperature in Celsius. - return_temperature_celsius : Union[xr.DataArray, np.array] - The return temperature in Celsius. + source_inlet_temperature_celsius : Union[xr.DataArray, np.array] + The source inlet temperature in Celsius. """ pass @@ -49,6 +67,19 @@ class BaseCopApproximator(ABC): def celsius_to_kelvin( t_celsius: Union[float, xr.DataArray, np.array] ) -> Union[float, xr.DataArray, np.array]: + """ + Convert temperature from Celsius to Kelvin. + + Parameters: + ---------- + t_celsius : Union[float, xr.DataArray, np.array] + Temperature in Celsius. + + Returns: + ------- + Union[float, xr.DataArray, np.array] + Temperature in Kelvin. + """ if (np.asarray(t_celsius) > 200).any(): raise ValueError( "t_celsius > 200. Are you sure you are using the right units?" @@ -60,6 +91,21 @@ class BaseCopApproximator(ABC): t_hot: Union[float, xr.DataArray, np.ndarray], t_cold: Union[float, xr.DataArray, np.ndarray], ) -> Union[float, xr.DataArray, np.ndarray]: + """ + Calculate the logarithmic mean temperature difference. + + Parameters: + ---------- + t_hot : Union[float, xr.DataArray, np.ndarray] + Hot temperature. + t_cold : Union[float, xr.DataArray, np.ndarray] + Cold temperature. + + Returns: + ------- + Union[float, xr.DataArray, np.ndarray] + Logarithmic mean temperature difference. + """ if (np.asarray(t_hot <= t_cold)).any(): raise ValueError("t_hot must be greater than t_cold") return (t_hot - t_cold) / np.log(t_hot / t_cold) diff --git a/scripts/build_cop_profiles/CentralHeatingCopApproximator.py b/scripts/build_cop_profiles/CentralHeatingCopApproximator.py index a29dab59..7bf15b30 100644 --- a/scripts/build_cop_profiles/CentralHeatingCopApproximator.py +++ b/scripts/build_cop_profiles/CentralHeatingCopApproximator.py @@ -20,8 +20,77 @@ class CentralHeatingCopApproximator(BaseCopApproximator): default parameters from Pieper et al. (2020). The method is based on a thermodynamic heat pump model with some hard-to-know parameters being approximated. - """ + Attributes: + ---------- + forward_temperature_celsius : Union[xr.DataArray, np.array] + The forward temperature in Celsius. + return_temperature_celsius : Union[xr.DataArray, np.array] + The return temperature in Celsius. + source_inlet_temperature_celsius : Union[xr.DataArray, np.array] + The source inlet temperature in Celsius. + source_outlet_temperature_celsius : Union[xr.DataArray, np.array] + The source outlet temperature in Celsius. + delta_t_pinch_point : float, optional + The pinch point temperature difference, by default 5. + isentropic_compressor_efficiency : float, optional + The isentropic compressor efficiency, by default 0.8. + heat_loss : float, optional + The heat loss, by default 0.0. + + Methods: + ------- + __init__( + forward_temperature_celsius: Union[xr.DataArray, np.array], + source_inlet_temperature_celsius: Union[xr.DataArray, np.array], + return_temperature_celsius: Union[xr.DataArray, np.array], + source_outlet_temperature_celsius: Union[xr.DataArray, np.array], + delta_t_pinch_point: float = 5, + isentropic_compressor_efficiency: float = 0.8, + heat_loss: float = 0.0, + ) -> None: + Initializes the CentralHeatingCopApproximator object. + + approximate_cop(self) -> Union[xr.DataArray, np.array]: + Calculate the coefficient of performance (COP) for the system. + + _approximate_delta_t_refrigerant_source( + self, delta_t_source: Union[xr.DataArray, np.array] + ) -> Union[xr.DataArray, np.array]: + Approximates the temperature difference between the refrigerant and the source. + + _approximate_delta_t_refrigerant_sink( + self, + refrigerant: str = "ammonia", + a: float = {"ammonia": 0.2, "isobutane": -0.0011}, + b: float = {"ammonia": 0.2, "isobutane": 0.3}, + c: float = {"ammonia": 0.016, "isobutane": 2.4}, + ) -> Union[xr.DataArray, np.array]: + Approximates the temperature difference between the refrigerant and heat sink. + + _ratio_evaporation_compression_work_approximation( + self, + refrigerant: str = "ammonia", + a: float = {"ammonia": 0.0014, "isobutane": 0.0035}, + ) -> Union[xr.DataArray, np.array]: + Calculate the ratio of evaporation to compression work based on approximation. + + _approximate_delta_t_refrigerant_sink( + self, + refrigerant: str = "ammonia", + a: float = {"ammonia": 0.2, "isobutane": -0.0011}, + b: float = {"ammonia": 0.2, "isobutane": 0.3}, + c: float = {"ammonia": 0.016, "isobutane": 2.4}, + ) -> Union[xr.DataArray, np.array]: + Approximates the temperature difference between the refrigerant and heat sink. + + _ratio_evaporation_compression_work_approximation( + self, + refrigerant: str = "ammonia", + a: float = {"ammonia": 0.0014, "isobutane": 0.0035}, + ) -> Union[xr.DataArray, np.array]: + Calculate the ratio of evaporation to compression work based on approximation. + """ def __init__( self, forward_temperature_celsius: Union[xr.DataArray, np.array], @@ -33,6 +102,7 @@ class CentralHeatingCopApproximator(BaseCopApproximator): heat_loss: float = 0.0, ) -> None: """ + Initializes the CentralHeatingCopApproximator object. Parameters: ---------- @@ -74,6 +144,7 @@ class CentralHeatingCopApproximator(BaseCopApproximator): Calculate the coefficient of performance (COP) for the system. Returns: + -------- Union[xr.DataArray, np.array]: The calculated COP values. """ return ( diff --git a/scripts/build_cop_profiles/DecentralHeatingCopApproximator.py b/scripts/build_cop_profiles/DecentralHeatingCopApproximator.py index 11be7407..d84b6795 100644 --- a/scripts/build_cop_profiles/DecentralHeatingCopApproximator.py +++ b/scripts/build_cop_profiles/DecentralHeatingCopApproximator.py @@ -16,7 +16,27 @@ class DecentralHeatingCopApproximator(BaseCopApproximator): Approximate the coefficient of performance (COP) for a heat pump in a decentral heating system (individual/household heating). - Uses a quadratic regression on the temperature difference between the source and sink based on empirical data proposed by Staffell et al. 2012 . + Uses a quadratic regression on the temperature difference between the source and sink based on empirical data proposed by Staffell et al. 2012. + + Attributes + ---------- + forward_temperature_celsius : Union[xr.DataArray, np.array] + The forward temperature in Celsius. + source_inlet_temperature_celsius : Union[xr.DataArray, np.array] + The source inlet temperature in Celsius. + source_type : str + The source of the heat pump. Must be either 'air' or 'ground'. + + Methods + ------- + __init__(forward_temperature_celsius, source_inlet_temperature_celsius, source_type) + Initialize the DecentralHeatingCopApproximator object. + approximate_cop() + Compute the COP values using quadratic regression for air-/ground-source heat pumps. + _approximate_cop_air_source() + Evaluate quadratic regression for an air-sourced heat pump. + _approximate_cop_ground_source() + Evaluate quadratic regression for a ground-sourced heat pump. References ---------- @@ -30,30 +50,32 @@ class DecentralHeatingCopApproximator(BaseCopApproximator): source_type: str, ): """ - Initialize the COPProfileBuilder object. + Initialize the DecentralHeatingCopApproximator object. - Parameters: + Parameters ---------- forward_temperature_celsius : Union[xr.DataArray, np.array] The forward temperature in Celsius. - return_temperature_celsius : Union[xr.DataArray, np.array] - The return temperature in Celsius. - source: str - The source of the heat pump. Must be either 'air' or 'ground' + source_inlet_temperature_celsius : Union[xr.DataArray, np.array] + The source inlet temperature in Celsius. + source_type : str + The source of the heat pump. Must be either 'air' or 'ground'. """ self.delta_t = forward_temperature_celsius - source_inlet_temperature_celsius if source_type not in ["air", "ground"]: - raise ValueError("'source' must be one of ['air', 'ground']") + raise ValueError("'source_type' must be one of ['air', 'ground']") else: self.source_type = source_type def approximate_cop(self) -> Union[xr.DataArray, np.array]: """ - Compute output of quadratic regression for air-/ground-source heat - pumps. + Compute the COP values using quadratic regression for air-/ground-source heat pumps. - Calls the appropriate method depending on `source`. + Returns + ------- + Union[xr.DataArray, np.array] + The calculated COP values. """ if self.source_type == "air": return self._approximate_cop_air_source()