From 84fcf9da49415270e1cee533e58900cc50e18b23 Mon Sep 17 00:00:00 2001 From: Khalim Conn-Kowlessar Date: Wed, 1 Jul 2026 13:03:28 +0000 Subject: [PATCH] =?UTF-8?q?Resolve=20biomass,=20dual-fuel=20and=20biodiese?= =?UTF-8?q?l=20water-heating=20overrides=20off=20house=20coal=20?= =?UTF-8?q?=F0=9F=9F=A9?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Co-Authored-By: Claude Opus 4.8 (1M context) --- .../epc/property_overlays/water_heating_overlay.py | 14 +++++++++++--- .../epc/property_overrides/water_heating_type.py | 3 +++ 2 files changed, 14 insertions(+), 3 deletions(-) diff --git a/domain/epc/property_overlays/water_heating_overlay.py b/domain/epc/property_overlays/water_heating_overlay.py index 290182c50..61b6a159f 100644 --- a/domain/epc/property_overlays/water_heating_overlay.py +++ b/domain/epc/property_overlays/water_heating_overlay.py @@ -26,10 +26,18 @@ _WATER_HEATING_CODES: dict[str, tuple[int, int]] = { "From main system, LPG (bulk)": (901, 27), "From main system, bottled LPG": (901, 3), "From main system, house coal": (901, 33), - # Wood logs — RdSAP water_heating_fuel 6 (biomass ~0.028 kgCO2/kWh), from - # main (901). A wood-fired individual-main dwelling's DHW must not fall to - # house coal 33 (~0.395), a ~14x carbon overstatement (ADR-0043). + # Biomass / wood water fuels routed off the house-coal dumping ground + # (ADR-0043), all from main (901) with their own RdSAP water_heating_fuel: + # 6 wood logs (biomass ~0.028 kgCO2/kWh vs house coal 33 ~0.395) + # 9 dual fuel (mineral + wood) + # 31 biomass (community) — scored via the coherent community main; the + # fuel is still emitted so an individual main would score biomass + # 34 biodiesel (community) + # A wood-fired individual-main dwelling's DHW must never fall to coal 33. "From main system, wood logs": (901, 6), + "From main system, dual fuel (mineral and wood)": (901, 9), + "From main system, biomass (community)": (901, 31), + "From main system, biodiesel (community)": (901, 34), "Electric immersion, electricity": (903, 29), # "boiler/circulator for water heating only" — SAP Table 4a code 911 (gas). "Gas boiler/circulator, mains gas": (911, 26), diff --git a/domain/epc/property_overrides/water_heating_type.py b/domain/epc/property_overrides/water_heating_type.py index 32e929acb..92cd3a75b 100644 --- a/domain/epc/property_overrides/water_heating_type.py +++ b/domain/epc/property_overrides/water_heating_type.py @@ -22,6 +22,9 @@ class WaterHeatingType(Enum): FROM_MAIN_BOTTLED_LPG = "From main system, bottled LPG" FROM_MAIN_HOUSE_COAL = "From main system, house coal" FROM_MAIN_WOOD_LOGS = "From main system, wood logs" + FROM_MAIN_DUAL_FUEL_MINERAL_WOOD = "From main system, dual fuel (mineral and wood)" + FROM_MAIN_BIOMASS_COMMUNITY = "From main system, biomass (community)" + FROM_MAIN_BIODIESEL_COMMUNITY = "From main system, biodiesel (community)" ELECTRIC_IMMERSION = "Electric immersion, electricity" GAS_BOILER_CIRCULATOR_MAINS_GAS = "Gas boiler/circulator, mains gas" UNKNOWN = "Unknown"