from recommendations.Costs import Costs, BOILER_UPGRADE_SCHEME_ASHP_VALUE from recommendations.recommendation_utils import check_simulation_difference, override_costs from backend.Property import Property from etl.epc_clean.epc_attributes.MainheatAttributes import MainHeatAttributes from etl.epc_clean.epc_attributes.HotWaterAttributes import HotWaterAttributes from etl.epc_clean.epc_attributes.MainFuelAttributes import MainFuelAttributes from recommendations.HeatingControlRecommender import HeatingControlRecommender class HeatingRecommender: ELECTRIC_HEATING_DESCRIPTIONS = [ "Room heaters, electric", "Electric storage heaters", "Electric storage heaters, radiators", "Portable electric heaters assumed for most rooms", ] high_heat_retention_contols_desc = "Controls for high heat retention storage heaters" def __init__(self, property_instance: Property): self.property = property_instance self.costs = Costs(self.property) self.heating_recommendations = [] self.heating_control_recommendations = [] self.has_electric_heating_description = ( self.property.main_heating["clean_description"] in self.ELECTRIC_HEATING_DESCRIPTIONS ) def is_high_heat_retention_valid(self): """ Check conditions if high heat retention storage is valid :return: """ # If the property has assumed electric heating, regardless of whether or not it has a mains connection, we # can consider hhr storage heaters electric_heating_assumed = ( self.property.main_heating["clean_description"] in ["No system present, electric heaters assumed"] ) return self.has_electric_heating_description or electric_heating_assumed def recommend(self, has_cavity_or_loft_recommendations, phase=0, exclusions=None): """ Produces heating recommendations :param has_cavity_or_loft_recommendations: boolean indicating if we have produced a cavity or loft insulation recommendation. If there are cavity or loft recommendations, the property would need to complete those measures before being able to get the boiler upgrade scheme benefits. The messaging in the front end would be to :param phase: indicates the phase of the retrofit programme :param exclusions: A list of exclusions for the recommendations """ # TODO: We could have a system flush recommendation for an existing boiler, where there is no need to replace # the boiler, but instead flushing the system will make it run more efficiently. There is a cost for this # in the Costs class, stored as SYSTEM_FLUSH_COST exclusions = [] if exclusions is None else exclusions self.heating_recommendations = [] self.heating_control_recommendations = [] # This first iteration of the recommender will provide very basic recommendation # We recommend heating controls based on the main heating system if self.is_high_heat_retention_valid(): # Recommend high heat retention storage heaters # TODO: We need to allow for the possibility that the property aleady has storage heaters, but just # needs the controls self.recommend_hhr_storage_heaters(phase=phase, system_change=True, heating_controls_only=False) # if the property has mains heating with boiler and radiators, we recommend optimal heating controls has_boiler = self.property.main_heating["clean_description"] in ["Boiler and radiators, mains gas"] # We also check that the property doesn't have a heating system, but it has access to the mains gas no_heating_has_mains = self.property.main_heating["clean_description"] in [ 'No system present, electric heaters assumed' ] and self.property.data["mains-gas-flag"] has_gas_heaters = ( self.property.main_heating["clean_description"] in ["Room heaters, mains gas"] and self.property.data["mains-gas-flag"] ) # We also check if the property has electric heating, but it has access to the mains gas electic_heating_has_mains = self.has_electric_heating_description and self.property.data["mains-gas-flag"] portable_heaters_has_mains = ( self.property.main_heating["clean_description"] in ["Portable electric heaters assumed for most rooms"] and self.property.data["mains-gas-flag"] ) if ( has_boiler or no_heating_has_mains or electic_heating_has_mains or has_gas_heaters or portable_heaters_has_mains ): # This indicates that the home previously did not have a boiler in place and so would require # an overhaul to the system - right now, this is all reasons, apart from if there is an existing boiler system_change = not has_boiler exising_room_heaters = self.property.main_heating["clean_description"] in [ "Room heaters, electric", "Room heaters, mains gas" ] self.recommend_boiler_upgrades( phase=phase, system_change=system_change, exising_room_heaters=exising_room_heaters ) # We recommend air source heat pumps # Heat pumps are suitable for all property types: # https://energysavingtrust.org.uk/from-flats-to-terraced-houses-heat-pumps-are-suitable-for-all-property-types/ # Just seems least probable for flats, so we'll allow houses and bungalows # In the future, we'll allow overrides, so that non-intrusive surveys can contradict these conditions # and either allow or prevent the recommendation of an air source heat pump if self.is_ashp_valid(exclusions=exclusions): self.recommend_air_source_heat_pump( phase=phase, has_cavity_or_loft_recommendations=has_cavity_or_loft_recommendations ) return def recommend_electric_boiler_upgrade(self, phase): # Small initial scope, just handles the case of properties that have electric boilers where the efficiency # is poor or very poor # We recommend upgrading to a new electric boiler recommendation_phase = phase if self.property.data["mainheat-energy-eff"] not in ["Poor", "Very Poor"]: return hotwater_from_mains = self.property.hotwater["clean_description"] in ["From main system"] hotwater_from_cylinder = self.property.hotwater["clean_description"] in [ "From main system, no cylinder thermostat" ] # if the hotwater is from the mains, we probably have a combi boiler so we recommend a new electric boiler if hotwater_from_mains: description = f"Upgrade to a higher efficiency electric boiler" simulation_config = { "mainheat_energy_eff_ending": "Average", "hot_water_energy_eff_ending": "Average" } boiler_costs = self.costs.boiler( size=None, exising_room_heaters=False, system_change=False, n_heated_rooms=self.property.data["number-heated-rooms"], n_rooms=self.property.number_of_rooms, is_electric=True ) already_installed = "heating" in self.property.already_installed if already_installed: boiler_costs = override_costs(boiler_costs) description = "Heating system has already been upgraded, no further action needed." boiler_recommendation = { "phase": recommendation_phase, "parts": [], "type": "heating", "description": description, "starting_u_value": None, "new_u_value": None, "sap_points": None, "already_installed": already_installed, "simulation_config": simulation_config, **boiler_costs } controls_recommender = HeatingControlRecommender(self.property) controls_recommender.recommend(heating_description="Boiler and radiators, electric") self.heating_recommendations.extend([boiler_recommendation] + controls_recommender.recommendation) return if hotwater_from_cylinder: # We recommend a change from a system boiler, with a cylinder to a combi boiler description = ("Replace the existing boiler and cylinder without a thermostat with a new electric combi " "boiler") def is_ashp_valid(self, exclusions): if "air_source_heat_pump" in self.property.non_invasive_recommendations: return True if "air_source_heat_pump" in exclusions: return False suitable_property_type = self.property.data["property-type"] in ["House", "Bungalow"] has_air_source_heat_pump = self.property.main_heating["has_air_source_heat_pump"] return suitable_property_type and not has_air_source_heat_pump def recommend_air_source_heat_pump(self, phase, has_cavity_or_loft_recommendations, _return=False): """ This method will implement the recommendation for an air source heat pump This is ultimately an overhaul to the heating system and so is recommended as an alternative to other heating system recommendations :return: """ controls_recommender = HeatingControlRecommender(self.property) controls_recommender.recommend(heating_description="Air source heat pump, radiators, electric") ashp_costs = self.costs.air_source_heat_pump() # We add the costs of the heating controls, onto each key in the costs dictionary if controls_recommender.recommendation: for key in ashp_costs: ashp_costs[key] += controls_recommender.recommendation[0][key] already_installed = "air_source_heat_pump" in self.property.already_installed if already_installed: ashp_costs = override_costs(ashp_costs) description = "The property already has an air source heat pump, no further action needed." else: if controls_recommender.recommendation: description = ("Install an air source heat pump, and upgrade heating controls to Smart Thermostats, " "room sensors and smart radiator valves (time & temperature zone control).") else: description = "Install an air source heat pump." # If the property does not have existing cavity and loft insulation, we include a note that the cost # includes the boiler upgrade scheme and that the cavity and loft need to be treated, to ensure access # to the funding if has_cavity_or_loft_recommendations: description = description + (f" The cost includes the £" f"{BOILER_UPGRADE_SCHEME_ASHP_VALUE} boiler upgrade scheme grant. " f"You must ensure that the property has an insulated cavity and " f"270mm+ loft insulation to qualify for the grant") else: description = description + (f" The cost includes the £" f"{BOILER_UPGRADE_SCHEME_ASHP_VALUE} boiler upgrade scheme grant") new_heating_description = "Air source heat pump, radiators, electric" new_hot_water_description = "From main system" simulation_config = { "mainheat_energy_eff_ending": "Good", "hot_water_energy_eff_ending": "Good" } description_simulation = { "mainheat-description": new_heating_description, "mainheat-energy-eff": simulation_config["mainheat_energy_eff_ending"], "hot-water-energy-eff": simulation_config["hot_water_energy_eff_ending"], "hotwater-description": new_hot_water_description, } # Installation of a boiler improves the hot water system so we need to reflect this in # the outcome of the recommendation heating_ending_config = MainHeatAttributes(new_heating_description).process() hotwater_ending_config = HotWaterAttributes(new_hot_water_description).process() # If the property does not currently have electric main fuel, we'll simulate the change fuel_ending_config = {} if self.property.main_fuel["fuel_type"] != "electricity": new_fuel_description = "electricity (not community)" fuel_ending_config = MainFuelAttributes(new_fuel_description).process() description_simulation = { **description_simulation, "main-fuel": new_fuel_description } # Check the simulation differences heating_simulation_config = check_simulation_difference( new_config=heating_ending_config, old_config=self.property.main_heating ) hotwater_simulation_config = check_simulation_difference( new_config=hotwater_ending_config, old_config=self.property.hotwater ) fuel_simulation_config = check_simulation_difference( new_config=fuel_ending_config, old_config=self.property.main_fuel ) simulation_config = { **simulation_config, **heating_simulation_config, **hotwater_simulation_config, **fuel_simulation_config, } if controls_recommender.recommendation: # We should have just the single recommendation for heat controls, which is time # and temperature zone controls if len(controls_recommender.recommendation) != 1: raise NotImplementedError("More than one heat controls recommendation for air source heat pump") simulation_config = { **simulation_config, **controls_recommender.recommendation[0]["simulation_config"] } description_simulation = { **description_simulation, **controls_recommender.recommendation[0]["description_simulation"] } ashp_recommendation = { "phase": phase, "parts": [ # TODO ], "type": "heating", "description": description, "starting_u_value": None, "new_u_value": None, "sap_points": None, "already_installed": already_installed, "simulation_config": simulation_config, "description_simulation": description_simulation, **ashp_costs } if _return: return [ashp_recommendation] self.heating_recommendations.append(ashp_recommendation) @staticmethod def check_simulation_difference(old_config, new_config): """ Given two dictionaries, that describe the heating control configurations, this method will compare the two and pick out the differences. These differences will be things that have been added and things that have been removed. This will be used to determine how we should be updating the configuration in the simulation :return: """ differences = {key + "_ending": new_config[key] for key in new_config if old_config[key] != new_config[key]} return differences def combine_heating_and_controls( self, controls_recommendations, heating_simulation_config, heating_description_simulation, costs, description, phase, heating_controls_only, system_change ): """ Given a recommendation for heating controls, and a recommendation for the heating system, we combine the two into a single recommendation :param controls_recommendations: The heating controls recommendations :param heating_simulation_config: The simulation configuration for the heating system :param heating_description_simulation: The simulation configuration for the heating description :param costs: The costs of the heating system :param description: The description of the recommendation :param phase: The phase of the recommendation :param heating_controls_only: If True, we will also add a recommendation for heating controls only :param system_change: Indicates if we are recommending a different type of heating system, compared to the current system. If we have a system change and we have a heat control recommendation, we only recommend both heating and controls together :return: """ # We produce recommendations with & without heating controls # We will also produce a recommendation for heating controls only heating_controls_switch = [True, False] if controls_recommendations else [False] if not heating_simulation_config: heating_controls_switch = [] if system_change and len(controls_recommendations): heating_controls_switch = [True] output = [] for controls_switch in heating_controls_switch: total_costs = costs.copy() recommendation_simulation_config = heating_simulation_config.copy() recommendation_description_simulation = heating_description_simulation.copy() recommendation_description = description if controls_switch: # We add the costs of the heating controls, onto each key in the costs dictionary for key in total_costs: total_costs[key] += controls_recommendations[0][key] recommendation_simulation_config = { **recommendation_simulation_config, **controls_recommendations[0]["simulation_config"] } recommendation_description_simulation = { **recommendation_description_simulation, **controls_recommendations[0]["description_simulation"] } controls_description = controls_recommendations[0]['description'] # Make the first letter of the description lowercase controls_description = ( controls_description[0].lower() + controls_description[1:] ) recommendation_description = f"{description} and {controls_description}" already_installed = "heating_controls" in self.property.already_installed if already_installed: total_costs = override_costs(total_costs) recommendation_description = "Heating system has already been upgraded, no further action needed." recommendation = { "phase": phase, "parts": [ # TODO ], "type": "heating", "description": recommendation_description, "starting_u_value": None, "new_u_value": None, "sap_points": None, "already_installed": already_installed, **total_costs, "simulation_config": recommendation_simulation_config, "description_simulation": recommendation_description_simulation } output.append(recommendation) if heating_controls_only and len(controls_recommendations): # Also add on a recommendation for heating controls only heating_control_recommendation = controls_recommendations[0].copy() # Capitalize the first letter of the description heating_control_recommendation["description"] = ( heating_control_recommendation["description"][0].upper() + heating_control_recommendation["description"][1:] ) output.append( { "phase": phase, "parts": [ # TODO ], "type": "heating", "starting_u_value": None, "new_u_value": None, "sap_points": None, **heating_control_recommendation } ) return output def is_hhr_already_installed(self): """ Check if the property already has high heat retention storage heaters :return: """ already_has_hhr = "Electric storage heaters" in self.property.main_heating["clean_description"] # Some electric storage heaters will show that the controls are "Manual charge controls" which are indicative # of the old model of electric storage heaters, originating from 1961. # Newer HHR storage heaters will charge up over night but will retain the heat durin the day for when warmth # is actually needed, unlike traditional storage heaters that charge up at night and release heat during the day # which isn't always ideal for the occupants. already_has_hhr_contols = ( self.property.main_heating_controls[ "clean_description" ].lower() == self.high_heat_retention_contols_desc.lower() ) return already_has_hhr and already_has_hhr_contols def recommend_hhr_storage_heaters(self, phase, system_change, heating_controls_only, _return=False): """ We will recommend upgrading to a high heat retention storage system, if the current system is not already high heat retention storage :param phase: The phase of the recommendation :param system_change: Indicates if we are recommending a different type of heating system, compared to the current system :param heating_controls_only: Indicates if we should include a recommendation for just heating controls :param _return: Indicates if we should return the recommendations, rather than appending them to the recommendations list :return: """ controls_recommender = HeatingControlRecommender(self.property) # The heating controls we're recommending for are based on the recommended heating system # We only recommend Celect-type controls if the current heating system is not Celect-type controls if self.property.main_heating_controls["clean_description"] != self.high_heat_retention_contols_desc: controls_recommender.recommend(heating_description="Electric storage heaters, radiators") has_hhr = self.is_hhr_already_installed() # Conditions for not recommending electric storage heaters if has_hhr: # No recommendation needed return new_heating_description = "Electric storage heaters, radiators" # Set up artefacts, suitable for the simulation and regardless of controls heating_ending_config = MainHeatAttributes(new_heating_description).process() heating_simulation_config = check_simulation_difference( new_config=heating_ending_config, old_config=self.property.main_heating ) # This upgrade will only take the heating system to average energy efficiency heating_simulation_config["mainheat_energy_eff_ending"] = "Average" # If the property is off-gas and has no heating system in place, the number of heated rooms will actually # be 0, so we use the number of rooms as the figure number_heated_rooms = ( self.property.data["number-heated-rooms"] if self.property.data["number-heated-rooms"] > 0 else ( self.property.number_of_rooms - 1 if self.property.number_of_rooms > 1 else self.property.number_of_rooms ) ) # Upgrade to electric storage heaters costs = self.costs.high_heat_electric_storage_heaters( number_heated_rooms=number_heated_rooms ) description = "Install high heat retention electric storage heaters" heating_description_simulation = { "mainheat-description": new_heating_description, "mainheat-energy-eff": heating_simulation_config["mainheat_energy_eff_ending"], } recommendations = self.combine_heating_and_controls( controls_recommendations=controls_recommender.recommendation, heating_simulation_config=heating_simulation_config, heating_description_simulation=heating_description_simulation, costs=costs, description=description, phase=phase, heating_controls_only=heating_controls_only, system_change=system_change ) if _return: return recommendations self.heating_recommendations.extend(recommendations) @staticmethod def estimate_boiler_size(property_type, built_form, floor_area, floor_height, num_heated_rooms): # Step 1: Base size estimation based on property type (as a starting point) base_size = { 'Flat': 25, 'House': 30, 'Maisonette': 28, 'Bungalow': 27 } # Step 2: Calculate the volume of the property volume = floor_area * floor_height # Step 3: Adjust base size for built form (to account for heat retention) form_adjustment = { 'Mid-Terrace': 0, 'End-Terrace': 2, 'Semi-Detached': 4, 'Detached': 6 } # Step 4: Further adjust for the total volume and number of heated rooms volume_adjustment = (volume / 100) # Simplified adjustment factor for volume rooms_adjustment = (num_heated_rooms - 5) * 0.5 # Assuming base case of 5 rooms # Calculate the estimated boiler size estimated_size = base_size[property_type] + form_adjustment[built_form] + volume_adjustment + rooms_adjustment # Step 5: Align with available boiler sizes and ensure it does not exceed 35kW, as it's rare to need more available_sizes = [30, 35, 40, 45, 50] estimated_size = min(max(estimated_size, 30), 40) # Ensure within 30kW to 35kW range # Find the closest available size (in this case, either rounding up or down to align with 30 or 35) closest_size = min(available_sizes, key=lambda x: abs(x - estimated_size)) return closest_size @staticmethod def estimate_electric_boiler_size(num_heated_rooms): """ We use the approach similar to as defined in https://www.greenmatch.co.uk/boilers/combi-boilers/electric-combi-boilers Instead of radiators as a proxy, we do the number of heated rooms :param num_heated_rooms: The number of heated rooms in the property :return: """ return max(num_heated_rooms * 1.5, 6) def recommend_boiler_upgrades(self, phase, system_change, exising_room_heaters): """ This boiler recommendation will only recommend a like-for-like upgrade, since changing the system is generally more expensive :param phase: :param system_change: Indicates if the property would be undergoing a heating system change. This could be true if the home didn't have a heating system in place, or if the home had electric heating previously :param exising_room_heaters: Indicates if the property had room heaters previously - if so, a boiler recommendation will need to be accompanied by removal of the room heaters :return: """ recommendation_phase = phase # We now recommend boiler upgrades, if applicable simulation_config = {} boiler_costs = {} boiler_recommendation = {} description_simulation = {} has_inefficient_space_heating = self.property.data["mainheat-energy-eff"] in ["Very Poor", "Poor", "Average"] has_inefficient_mains_water = ( self.property.hotwater["clean_description"] in ["From main system"] and self.property.data["hot-water-energy-eff"] in ["Very Poor", "Poor", "Average"] ) if has_inefficient_space_heating or has_inefficient_mains_water: boiler_size = self.estimate_boiler_size( property_type=self.property.data["property-type"], built_form=self.property.data["built-form"], floor_area=self.property.floor_area, floor_height=self.property.floor_height, num_heated_rooms=self.property.data["number-heated-rooms"], ) description = "Upgrade to a new condensing boiler" simulation_config = { "mainheat_energy_eff_ending": "Good", "hot_water_energy_eff_ending": "Good" } description_simulation = { "mainheat-energy-eff": simulation_config["mainheat_energy_eff_ending"], "hot-water-energy-eff": simulation_config["hot_water_energy_eff_ending"], } if system_change: # Installation of a boiler improves the hot water system so we need to reflect this in # the outcome of the recommendation new_heating_description = "Boiler and radiators, mains gas" new_hotwater_description = "From main system" new_fuel_description = "mains gas (not community)" heating_ending_config = MainHeatAttributes(new_heating_description).process() hotwater_ending_config = HotWaterAttributes(new_hotwater_description).process() fuel_ending_config = MainFuelAttributes(new_fuel_description).process() heating_simulation_config = check_simulation_difference( new_config=heating_ending_config, old_config=self.property.main_heating ) hotwater_simulation_config = check_simulation_difference( new_config=hotwater_ending_config, old_config=self.property.hotwater ) fuel_simulation_config = check_simulation_difference( new_config=fuel_ending_config, old_config=self.property.main_fuel ) simulation_config = { **simulation_config, **heating_simulation_config, **hotwater_simulation_config, **fuel_simulation_config, } description_simulation = { **description_simulation, "mainheat-description": new_heating_description, "hotwater-description": new_hotwater_description, "main-fuel": new_fuel_description } boiler_costs = self.costs.boiler( size=f"{boiler_size}kw", exising_room_heaters=exising_room_heaters, system_change=system_change, n_heated_rooms=self.property.data["number-heated-rooms"], n_rooms=self.property.number_of_rooms ) already_installed = "heating" in self.property.already_installed if already_installed: boiler_costs = override_costs(boiler_costs) description = "Heating system has already been upgraded, no further action needed." boiler_recommendation = { "phase": recommendation_phase, "parts": [ # TODO ], "type": "heating", "description": description, "starting_u_value": None, "new_u_value": None, "sap_points": None, "already_installed": already_installed, "simulation_config": simulation_config, "description_simulation": description_simulation, **boiler_costs } # We recommend the heating controls # If the property did not previously have a boiler, we combine controls_recommender = HeatingControlRecommender(self.property) controls_recommender.recommend(heating_description="Boiler and radiators, mains gas") # We may have 2 recommendations from the heating controls if not controls_recommender.recommendation and not boiler_recommendation: return if not system_change and len(boiler_recommendation): # If there is not a system change, we add the boiler recommendation at point. self.heating_recommendations.extend([boiler_recommendation]) if system_change: # We combine the heating and controls recommendations, in the case of a system change combined_recommendations = [] for controls_recommendation in controls_recommender.recommendation: combined_recommendation = self.combine_heating_and_controls( controls_recommendations=[controls_recommendation], heating_simulation_config=simulation_config, heating_description_simulation=description_simulation, costs=boiler_costs, description=boiler_recommendation["description"], phase=recommendation_phase, heating_controls_only=False, system_change=True ) combined_recommendations.extend(combined_recommendation) # Overwrite the existing boiler recommendation self.heating_recommendations.extend(combined_recommendations) else: # We increment the recommendation phase, since the heating controls are separate from the boiler upgrade # but we'll only upgrade if we have a heating recommendation has_heating_recommendation = any( rec["type"] == "heating" for rec in self.heating_recommendations ) if has_heating_recommendation: recommendation_phase += 1 # The heating controls recommendation is distrinct from the boiler upgrade recommendation # We insert phase into the recommendations for heating controls for recommendation in controls_recommender.recommendation: recommendation["phase"] = recommendation_phase self.heating_control_recommendations.extend(controls_recommender.recommendation) return