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Solar Resource Loss

Overview

The SolarEnergyLossResource class is a subclass of SolarEnergyLossCalculator and FeatureCalculator that calculates the value of solar power resource loss/gain production using a linear polynomial regression model. Currently this class expects that the model has been trained and saved as a pickle file in calculation_model table.

This class uses a pre-trained linear polynomial regression model from sklearn lybraries. It considers Plane of Array Irradiance and Module Temperature from PVSyst simulations as input and Expected Energy on Point of Connection level as output. PVSyst simulations were used to train this model since the current company targets uses these simulations as base. The model is trained per SPE and the script used to do this training process can be found in the performance server at manual_routines\solar_resource_loss.

Calculation Logic

The calculation works as follows:

  1. Get IrradiancePOA and ModuleTemp from simple weather stations of each SPE and calculate the average values.
  2. Resample data to daily frequency
  3. Load the Linear Polynomial Regression Model from the database.
  4. Perform calculation only during complete days (for example, if you define period as from 00:00 01-01-2025 until 15:00 02-01-2025, the calculation will be done only in 01-01-2025 because it has all timestamps from that date)
  5. Perform calculation to get Losses value (P50 Long Term Target minus the result from Regression Model)

Database Requirements

  • Feature attribute server_calc_type must be set to 'solar_energy_loss_resource'.
  • Feature attribute feature_options_json with the following keys:

    • calc_model_type: Type of the calculation model that will be used to calculate the feature. In the case: 'solar_resource_fit'.
    • model_name: The name os the model to pe considered on the feature calculation. In the case: 'solar_resource_regression'
    • bazefield_features: A boolean indicating if the features comes from bazefield or not. For the solar prediction to work today, all values comes from bazefield database.

    Keep in mind that 'calc_model_type' and 'model_name' are only used to find the desired calculation model in the database. See views v_calculation_models and v_calculation_models_files_def for more details.

  • The following object attributes for the object that is being calculated:

    • Required:
      • reference_weather_stations: A dict indicating which simple weather station to be considered during data acquisition. Example: {"simple_ws": "RBG-RBG2-MET1"}

Class Definition

SolarEnergyLossResource(object_name, feature)

Base class for solar energy loss/gain from Irradiance.

For this class to work, the feature must have the attribute feature_options_json with the following keys:

  • 'calc_model_type': type of the model that will be used to calculate the feature. It must match the type of the model in performance_db.
  • 'model_name': name of the model that will be used to calculate the feature.
  • 'bazefield_features': bool indicating if the required features needs to be acquired from bazefield.

Parameters:

  • object_name

    (str) –

    Name of the object for which the feature is calculated. It must exist in performance_db.

  • feature

    (str) –

    Feature of the object that is calculated. It must exist in performance_db.

Source code in echo_energycalc/solar_energy_loss_resource.py
def __init__(self, object_name: str, feature: str) -> None:
    """
    Class used to calculate features that depend on a PredictiveModel.

    For this class to work, the feature must have the attribute `feature_options_json` with the following keys:

    - 'calc_model_type': type of the model that will be used to calculate the feature. It must match the type of the model in performance_db.
    - 'model_name': name of the model that will be used to calculate the feature.
    - 'bazefield_features': bool indicating if the required features needs to be acquired from bazefield.

    Parameters
    ----------
    object_name : str
        Name of the object for which the feature is calculated. It must exist in performance_db.
    feature : str
        Feature of the object that is calculated. It must exist in performance_db.
    """
    # initialize parent class
    super().__init__(object_name, feature)

    self._add_requirement(RequiredFeatureAttributes(self.object, self.feature, ["feature_options_json"]))

    self._get_required_data()

    self._feature_attributes = self._get_requirement_data("RequiredFeatureAttributes")[self.feature]

    self._validate_feature_options()

    self._add_requirement(
        RequiredCalcModels(
            calc_models={
                self.object: [
                    {
                        "model_name": f".*{self._feature_attributes['feature_options_json']['model_name']}.*",
                        "model_type": f"^{self._feature_attributes['feature_options_json']['calc_model_type']}$",
                    },
                ],
            },
        ),
    )
    self._add_requirement(
        RequiredObjectAttributes(
            {
                self.object: [
                    "reference_weather_stations",
                    "latitude",
                    "longitude",
                ],
            },
        ),
    )
    self._get_required_data()

    # getting the model name
    self._model_name = next(iter(self._get_requirement_data("RequiredCalcModels")[self.object].keys()))

    # loading calculation model from file
    self._model = self._get_requirement_data("RequiredCalcModels")[self.object][self._model_name]["model"]

    # Deserializing the model from base64
    if self._model is None:
        raise ValueError(
            f"Model {self._model_name} not found for object {self.object}. Please check the configuration in the database.",
        )
    model_b64_loaded = self._model["model"]
    with BytesIO(pybase64.b64decode(model_b64_loaded)) as buffer:
        buffer.seek(0)
        self._model = joblib.load(buffer)

    # defining required features
    simple_ws = self._get_requirement_data("RequiredObjectAttributes")[self.object]["reference_weather_stations"]["simple_ws"]
    features = {ws: ["IrradiancePOACommOk_5min.AVG"] for ws in simple_ws}

    # Adding suffix _b# to features if bazefield_features is True
    if self._feature_attributes["feature_options_json"].get("bazefield_features", False):
        features = {obj: [f"{feat}_b#" for feat in feats] for obj, feats in features.items()}
    self._add_requirement(RequiredFeatures(features=features))

feature property

Feature that is calculated. This will be defined in the constructor and cannot be changed.

Returns:

  • str

    Name of the feature that is calculated.

name property

Name of the feature calculator. Is defined in child classes of FeatureCalculator.

This must be equal to the "server_calc_type" attribute of the feature in performance_db.

Returns:

  • str

    Name of the feature calculator.

object property

Object for which the feature is calculated. This will be defined in the constructor and cannot be changed.

Returns:

  • str

    Object name for which the feature is calculated.

requirements property

List of requirements of the feature calculator. Is defined in child classes of FeatureCalculator.

Returns:

  • dict[str, list[CalculationRequirement]]

    Dict of requirements.

    The keys are the names of the classes of the requirements and the values are lists of requirements of that class.

    For example: {"RequiredFeatures": [RequiredFeatures(...), RequiredFeatures(...)], "RequiredObjects": [RequiredObjects(...)]}

result property

Result of the calculation. This is None until the method "calculate" is called.

Returns:

  • Series | DataFrame | None:

    Result of the calculation if the method "calculate" was called. None otherwise.

calculate(period, save_into=None, cached_data=None, **kwargs)

Method that will calculate the feature.

This code will do the following: 1. Get irradiance data from the weather stations associated with the object. 2. Average the irradiance data from all weather stations. 3. Resample the data to daily frequency, keeping only complete days (24 hours of data). 4. Predict the energy production using the model. 5. Get the target energy production from performance_db (P50) as used in current budget. 6. Calculate the energy loss as the difference between the target energy production and the predicted energy production.

Parameters:

  • period

    (DateTimeRange) –

    Period for which the feature will be calculated.

  • save_into

    (Literal['all', 'performance_db'] | None, default: None ) –

    Argument that will be passed to the method "save". The options are: - "all": The feature will be saved in performance_db and bazefield. - "performance_db": the feature will be saved only in performance_db. - None: The feature will not be saved.

    By default None.

  • cached_data

    (DataFrame | None, default: None ) –

    DataFrame with features already queried/calculated. This is useful to avoid needing to query all the data again from performance_db, making chained calculations a lot more efficient. By default None

  • **kwargs

    (dict, default: {} ) –

    Additional arguments that will be passed to the "save" method.

Returns:

  • Series

    Pandas Series with the calculated feature.

Source code in echo_energycalc/solar_energy_loss_resource.py
def calculate(
    self,
    period: DateTimeRange,
    save_into: Literal["all", "performance_db"] | None = None,
    cached_data: DataFrame | None = None,
    **kwargs,
) -> Series:
    """
    Method that will calculate the feature.

    This code will do the following:
    1. Get irradiance data from the weather stations associated with the object.
    2. Average the irradiance data from all weather stations.
    3. Resample the data to daily frequency, keeping only complete days (24 hours of data).
    4. Predict the energy production using the model.
    5. Get the target energy production from performance_db (P50) as used in current budget.
    6. Calculate the energy loss as the difference between the target energy production and the predicted energy production.

    Parameters
    ----------
    period : DateTimeRange
        Period for which the feature will be calculated.
    save_into : Literal["all", "performance_db"] | None, optional
        Argument that will be passed to the method "save". The options are:
        - "all": The feature will be saved in performance_db and bazefield.
        - "performance_db": the feature will be saved only in performance_db.
        - None: The feature will not be saved.

        By default None.
    cached_data : DataFrame | None, optional
        DataFrame with features already queried/calculated. This is useful to avoid needing to query all the data again from performance_db, making chained calculations a lot more efficient.
        By default None
    **kwargs : dict, optional
        Additional arguments that will be passed to the "save" method.

    Returns
    -------
    Series
        Pandas Series with the calculated feature.
    """
    t0 = perf_counter()
    # adjusting period to account for lagged timestamps
    adjusted_period = period.copy()
    # creating a series to store the result
    result_aux = self._create_empty_result(period=adjusted_period, freq="D", result_type="Series")

    # getting feature values
    self._get_required_data(
        period=adjusted_period,
        reindex=None,
        round_timestamps={"freq": timedelta(minutes=5), "tolerance": timedelta(minutes=2)},
        cached_data=cached_data,
    )

    t1 = perf_counter()

    # getting DataFrame with feature values
    df = self._get_requirement_data("RequiredFeatures")

    # Averaging the values for the features
    df[("AVG", "IrradiancePOACommOk_5min.AVG")] = df.loc[:, (slice(None), "IrradiancePOACommOk_5min.AVG_b#")].mean(axis=1)

    # Adjusting Dataframe structure
    df = df.loc[:, df.columns.get_level_values("object") == "AVG"]
    df.columns = df.columns.droplevel(0)
    # Remove the suffix _b# from the columns
    df.columns = df.columns.str.replace("_b#$", "", regex=True)
    # Renaming columns to match the model input
    df = df.rename(
        columns={
            "IrradiancePOACommOk_5min.AVG": "GlobInc",
        },
    )

    # Resampling the dataframe to hour frequency to filter only complete days from the period
    df = df.resample("h").mean()
    daily_counts = df.resample("D").size()
    complete_days = daily_counts[daily_counts == 24].index
    df_complete_days = df[df.index.normalize().isin(complete_days)]

    # Adjusting irradiance night values to 0 if NaN

    # Getting timestamps and converting to UTC
    timestamps = df_complete_days.index
    # adding 3 hours to convert to UTC
    times_pd = timestamps + Timedelta(hours=3)
    solar_position = pvlib.solarposition.get_solarposition(
        time=times_pd,
        latitude=self._get_requirement_data("RequiredObjectAttributes")[self.object]["latitude"],
        longitude=self._get_requirement_data("RequiredObjectAttributes")[self.object]["longitude"],
    )
    # Get the sun's elevation (altitude)
    # Sun altitude < 0 means the sun is below the horizon (night)
    is_night = solar_position["elevation"] < 0
    # Reset index to match df timestamps (convert back from UTC to local time)
    is_night.index = timestamps
    df_complete_days.loc[is_night, "GlobInc"] = df_complete_days.loc[is_night, "GlobInc"].fillna(0)

    # Resampling the DataFrame to daily frequency only for complete days
    df_resampled = df_complete_days.resample("D").sum()

    # Logging discarded days due to incomplete data
    discarded_days = set(df.index.normalize()) - set(df_resampled.index.normalize())
    if discarded_days:
        logger.warning(
            f"{self.object} - {self.feature} - {period}: Discarded days due to less than 24 hours of data: {', '.join(str(day.date()) for day in discarded_days)}",
        )

    t2 = perf_counter()

    if not df.empty:
        # Predicting feature values
        model_result = self._model.predict(df_resampled)
        model_result_series = Series(model_result, index=df_resampled.index, name="value")
        wanted_idx = result_aux.index.intersection(df_resampled.index)
        result_aux.loc[wanted_idx] = model_result_series[wanted_idx]
        # Converting daily result to kWmed
        result_aux = result_aux / 24
        # Getting target values from performance database
        # Getting witch target_pxx is used on the given period
        target_pxx = self._perfdb.kpis.energy.targets.get(
            period=adjusted_period,
            time_res="daily",
            object_or_group_names=[self.object],
            measurement_points=["Connection Point"],
            values_only=True,
        )
        # quero pegar o valor unico da minha coluna target_pxx["target_pxx"]
        if len(target_pxx["target_pxx"].unique()) != 1:
            raise ValueError(
                f"Multiple target pxx values found for object {self.object} in the period {adjusted_period}. Cannot proceed with calculation. Please select a period with a single target pxx value for this object.",
            )
        target_pxx_value = target_pxx["target_pxx"].unique()[0]
        target_evaluation_period = target_pxx["target_evaluation_period"].unique()[0]
        target_energy_df = self._perfdb.resourceassessments.pxx.get(
            period=adjusted_period,
            time_res="daily",
            pxx=[target_pxx_value],
            evaluation_periods=[target_evaluation_period],
            group_names=[self.object],
            resource_types=["average_power"],
            output_type="DataFrame",
        )
        new_index = target_energy_df.index.get_level_values(4)
        target_energy = Series(target_energy_df["value"].values, index=new_index, name="value")
        result = target_energy - result_aux
        # Triming result index to the adjusted period
        result = result.loc[(result.index >= adjusted_period.start) & (result.index < adjusted_period.end)]
        result.index = to_datetime(result.index)

    t3 = perf_counter()

    # adding calculated feature to class result attribute
    self._result = result.copy()

    # saving results
    self.save(save_into=save_into, **kwargs)

    logger.debug(
        f"{self.object} - {self.feature} - {period}: Requirements during calc {t1 - t0:.2f}s - Data adjustments {t2 - t1:.2f}s - Model prediction {t3 - t2:.2f}s - Saving data {perf_counter() - t3:.2f}s",
    )

    return result_aux

save(save_into=None, **kwargs)

Method to save the calculated feature values in performance_db.

Parameters:

  • save_into

    (Literal['all', 'performance_db'] | None, default: None ) –

    Argument that will be passed to the method "save". The options are: - "all": The feature will be saved in performance_db and bazefield. - "performance_db": the feature will be saved only in performance_db. - None: The feature will not be saved.

    By default None.

  • **kwargs

    (dict, default: {} ) –

    Not being used at the moment. Here only for compatibility.

Source code in echo_energycalc/feature_calc_core.py
def save(
    self,
    save_into: Literal["all", "performance_db"] | None = None,
    **kwargs,  # noqa: ARG002
) -> None:
    """
    Method to save the calculated feature values in performance_db.

    Parameters
    ----------
    save_into : Literal["all", "performance_db"] | None, optional
        Argument that will be passed to the method "save". The options are:
        - "all": The feature will be saved in performance_db and bazefield.
        - "performance_db": the feature will be saved only in performance_db.
        - None: The feature will not be saved.

        By default None.
    **kwargs : dict, optional
        Not being used at the moment. Here only for compatibility.
    """
    # checking arguments
    if not isinstance(save_into, str | type(None)):
        raise TypeError(f"save_into must be a string or None, not {type(save_into)}")
    if isinstance(save_into, str) and save_into not in ["all", "performance_db"]:
        raise ValueError(f"save_into must be 'all', 'performance_db' or None, not {save_into}")

    # checking if calculation was done
    if self.result is None:
        raise ValueError(
            "The calculation was not done. Cannot save the feature calculation results. Please make sure to do something like 'self._result = df[self.feature].copy()' in the method 'calculate' before calling 'self.save()'.",
        )

    if save_into is None:
        return

    if isinstance(save_into, str):
        if save_into not in ["performance_db", "all"]:
            raise ValueError(f"save_into must be 'performance_db' or 'all', not {save_into}.")
        upload_to_bazefield = save_into == "all"
    elif save_into is None:
        upload_to_bazefield = False
    else:
        raise TypeError(f"save_into must be a string or None, not {type(save_into)}.")

    # converting result series to DataFrame if needed
    if isinstance(self.result, Series):
        result_df = self.result.to_frame()
    elif isinstance(self.result, DataFrame):
        result_df = self.result.droplevel(0, axis=1)
    else:
        raise TypeError(f"result must be a pandas Series or DataFrame, not {type(self.result)}.")

    # adjusting DataFrame to be inserted in the database
    # making the columns a Multindex with levels object_name and feature_name
    result_df.columns = MultiIndex.from_product([[self.object], result_df.columns], names=["object_name", "feature_name"])

    self._perfdb.features.values.series.insert(
        df=result_df,
        on_conflict="update",
        bazefield_upload=upload_to_bazefield,
    )