Emissionary — data sources and methodology

Generated by scripts/generate-sources-md.ts — do not edit by hand.

Scope and boundary

All figures are use-phase (operational) CO₂ only: the energy consumed while using a product, multiplied by the emission factor of the energy carrier. Manufacturing, embodied carbon, and end-of-life are out of scope. The boundary is symmetric: combustion-only factors for fuels (no well-to-tank) and generation-based grid intensity for electricity (no upstream fuel supply). Gaseous fuel factors use the gross calorific value basis, which pairs consistently with US DOE appliance efficiencies (measured on the HHV basis) and with how gas is metered.

Core factors

• Natural gas: 182.59 gCO₂/kWh thermal, gross CV (DESNZ 2025, CO₂-only component)
• LPG: 214.19 gCO₂/kWh thermal, gross CV (DESNZ 2025)
• Petrol: 2.32567 kgCO₂/L (100% mineral, tailpipe, DESNZ 2025)
• Diesel: 2.62818 kgCO₂/L (100% mineral, tailpipe, DESNZ 2025)
• Grid intensity: yearly gCO₂/kWh per country, Ember (latest year per country; see country_factors.json)
• Water heating: 0.093 kWh useful per liter boiled from 20 °C (4.186 kJ/kg·K × 80 K)

Source registry

codata_physics

NIST — NIST Chemistry WebBook — thermophysical properties of water (specific heat 4.186 kJ/kg·K) (2023). License: Public domain (US federal). Retrieved 2026-07-16. https://webbook.nist.gov/chemistry/fluid/

desnz_2025

UK Government (DESNZ) — Greenhouse gas reporting: conversion factors 2025 (flat file, CO₂-only components) (2025). License: Open Government Licence v3.0. Retrieved 2026-07-16. https://www.gov.uk/government/publications/greenhouse-gas-reporting-conversion-factors-2025

doe_energysaver

US DOE — Energy Saver — appliances and home electronics guidance (typical product-class rated powers; used where no certified dataset exists — flagged for EPREL verification in SOURCES.md) (2026). License: Public domain (US federal). Retrieved 2026-07-16. https://www.energy.gov/energysaver/appliances-and-electronics

doe_tsd_cooking

US DOE — Technical Support Document for Residential Cooking Products (docket EERE-2006-STD-0070): cooking efficiency of gas (~40%) and electric coil (~74%) cooktops (2009). License: Public domain (US federal). Retrieved 2026-07-16. https://downloads.regulations.gov/EERE-2006-STD-0070-0053/content.pdf

ember_yearly

Ember — Yearly electricity data — CO₂ intensity of electricity generation (retrieved via Our World in Data grapher mirror) (2026). License: CC BY 4.0. Retrieved 2026-07-16. https://ourworldindata.org/grapher/carbon-intensity-electricity

energystar

US EPA ENERGY STAR — ENERGY STAR certified product datasets (data.energystar.gov); medians computed from full dataset on retrieval date (2026). License: Public domain (US federal). Retrieved 2026-07-16. https://data.energystar.gov

energystar_induction

US EPA ENERGY STAR — 2021–2022 Residential Induction Cooking Tops program page (~84% induction cooking efficiency) (2021). License: Public domain (US federal). Retrieved 2026-07-16. https://www.energystar.gov/partner-resources/products_partner_resources/brand-owner/eta-consumers/res-induction-cooking-tops

epa_fueleconomy

US EPA / DOE — fueleconomy.gov vehicle data — 2024 Tesla Model Y Long Range AWD (vehicle id 47913), EPA combined 28.7 kWh/100 mi wall-to-wheels (2024). License: Public domain (US federal). Retrieved 2026-07-16. https://www.fueleconomy.gov/feg/Find.do?action=sbs&id=47913

epa_trends

US EPA — The 2024 EPA Automotive Trends Report — MY2023 new-vehicle real-world CO₂ (319 g/mi incl. BEV; +38 g/mi excluding BEV/PHEV) (2024). License: Public domain (US federal). Retrieved 2026-07-16. https://www.epa.gov/automotive-trends

ipcc_2006_v2

IPCC — 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Volume 2: Energy (stationary combustion defaults) (2006). License: IPCC publication terms. Retrieved 2026-07-16. https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html

Items

Item	Value	Year	Sources
🍟 Air fryer (air_fryer)	1500 W (electricity)	2026	doe_energysaver
🪭 Ceiling fan (ceiling_fan)	29.8 W (electricity)	2026	energystar
❄️ Freezer (chest_freezer)	46.2 W (electricity)	2026	energystar
🚌 City bus (per passenger) (city_bus)	103.11 gCO₂/km	2025	desnz_2025
🚐 Intercity coach (per passenger) (coach)	27.27 gCO₂/km	2025	desnz_2025
💧 Dehumidifier (dehumidifier)	313 W (electricity)	2026	energystar
🖥️ Computer monitor (desktop_monitor)	28.7 W (electricity)	2026	energystar
🚙 Diesel car (diesel_car)	171.36 gCO₂/km	2025	desnz_2025
🍽️ Dishwasher (dishwasher)	1.11 kWh/cycles	2026	energystar
🚲 E-bike (e_bike)	0.011 kWh/km	2026	codata_physics
🛏️ Electric blanket (electric_blanket)	150 W (electricity)	2026	doe_energysaver
🍳 Electric coil hob (boiling) (electric_hob)	0.093 kWh useful/L ÷ 74% (electricity)	2009	codata_physics, doe_tsd_cooking
🫖 Electric kettle (electric_kettle)	0.093 kWh useful/L ÷ 85% (electricity)	2009	codata_physics, doe_tsd_cooking
🥧 Electric oven (electric_oven)	2000 W (electricity)	2026	doe_energysaver
🚿 Shower (electric water heater) (electric_shower)	9500 W (electricity)	2026	doe_energysaver
🪥 Electric toothbrush (electric_toothbrush)	0.002 kWh/charges	2026	codata_physics
📚 E-reader charge (ereader_charge)	0.006 kWh/charges	2026	codata_physics
☕ Espresso machine (espresso_machine)	0.02 kWh/espressos	2026	codata_physics
🔌 Electric car (ev_car)	0.178 kWh/km	2024	epa_fueleconomy
✈️ Flight, short-haul (per passenger) (flight_short_haul)	73.44 gCO₂/km	2025	desnz_2025
🕹️ Game console (game_console)	160 W (electricity)	2026	doe_energysaver
🎮 Gaming PC (gaming_pc)	350 W (electricity)	2026	doe_energysaver
🏠 Gas boiler (heating) (gas_boiler)	12000 W (natural_gas)	2026	doe_energysaver, desnz_2025
🔥 Gas hob (boiling) (gas_hob)	0.093 kWh useful/L ÷ 40% (natural_gas)	2025	codata_physics, doe_tsd_cooking, desnz_2025
🍗 Gas oven (gas_oven)	3000 W (natural_gas)	2026	doe_energysaver, desnz_2025
💇 Hair straightener (hair_straightener)	120 W (electricity)	2026	doe_energysaver
💨 Hairdryer (hairdryer)	1800 W (electricity)	2026	doe_energysaver
♻️ Heat pump (heating) (heat_pump)	800 W (electricity)	2026	doe_energysaver
🔦 800-lumen incandescent bulb (incandescent_bulb)	60 W (electricity)	2026	doe_energysaver
🌟 1600-lumen incandescent bulb (incandescent_bulb_1600)	100 W (electricity)	2026	doe_energysaver
🧲 Induction hob (boiling) (induction_hob)	0.093 kWh useful/L ÷ 84% (electricity)	2021	codata_physics, energystar_induction
👕 Clothes iron (iron)	1400 W (electricity)	2026	doe_energysaver
💻 Laptop (laptop)	50 W (electricity)	2026	doe_energysaver
💡 800-lumen LED bulb (led_bulb)	9 W (electricity)	2026	doe_energysaver
🔆 1600-lumen LED bulb (led_bulb_1600)	16 W (electricity)	2026	doe_energysaver
🍿 Microwave oven (microwave)	1100 W (electricity)	2026	doe_energysaver
🛵 Motor scooter (motor_scooter)	80.94 gCO₂/km	2025	desnz_2025
🚗 Petrol car (petrol_car)	country average gCO₂/km	2025	desnz_2025, epa_trends
🧊 Refrigerator (refrigerator)	39.4 W (electricity)	2026	energystar
🌬️ Air conditioner (room) (room_ac)	800 W (electricity)	2026	energystar
🔊 Smart speaker (smart_speaker)	3 W (electricity)	2026	doe_energysaver
📱 Smartphone charge (smartphone_charge)	0.015 kWh/charges	2026	codata_physics
♨️ Electric space heater (space_heater)	1500 W (electricity)	2026	doe_energysaver
📲 Tablet charge (tablet_charge)	0.033 kWh/charges	2026	codata_physics
🍞 Toaster (toaster)	1000 W (electricity)	2026	doe_energysaver
🚆 Train (per passenger) (train_national)	35.1 gCO₂/km	2025	desnz_2025
🌀 Tumble dryer (tumble_dryer)	2.15 kWh/loads	2026	energystar
📺 55″ LED TV (tv_55)	97.5 W (electricity)	2026	energystar
🧹 Vacuum cleaner (vacuum_cleaner)	1200 W (electricity)	2026	doe_energysaver
🧺 Washing machine (washing_machine)	0.47 kWh/loads	2026	energystar
📶 Wi-Fi router (wifi_router)	8 W (electricity)	2026	doe_energysaver

Verification status

33 of 51 item values come from certified datasets, government conversion factors, regulated test data, or first-principles physics. The following 18 use documented product-class conventions and are flagged for verification against EPREL / measured datasets:

• microwave — Typical countertop microwave draws ~1,100 W while heating (product-class rated input, range 900–1,500 W). Pending certified-dataset verification.
• electric_oven — Electric oven at ~200 °C averages ~2.0 kWh per hour of use, element cycling included (product-class convention). Pending certified-dataset verification.
• espresso_machine — One espresso ≈ 0.02 kWh: heating ~40 mL of brew water plus boiler losses (physics estimate; range 0.01–0.05 kWh). Pending measured verification.
• toaster — Typical 2-slice toaster rated ~1,000 W (product-class range 800–1,500 W). Pending certified-dataset verification.
• air_fryer — Typical air fryer rated ~1,500 W, element cycling brings averages slightly lower (product-class range 1,200–1,800 W). Pending verification.
• heat_pump — A heat pump delivering ~2.8 kW of heat at seasonal COP ~3.5 draws ~800 W of electricity — about 0.29 kWh electric per kWh of heat. Pending dataset verification.
• gas_boiler — A home gas boiler actively heating burns ~12 kW of gas (thermal; modulating range 8–24 kW). Country-invariant. Pending dataset verification.
• electric_blanket — Typical double electric blanket rated ~150 W on high (product-class range 60–200 W). Pending verification.
• hairdryer — Typical consumer hairdryer on high: ~1,800 W (product-class range 1,200–2,200 W). Pending certified-dataset verification.
• hair_straightener — Hair straighteners average ~120 W once at temperature (class range 40–300 W). Pending verification.
• iron — Typical steam iron rated ~1,400 W; thermostat cycling lowers averages (class range 1,000–1,800 W). Pending verification.
• vacuum_cleaner — Corded vacuum cleaners draw ~1,200 W (class range 500–1,800 W; EU ecodesign caps at 900 W). Pending verification.
• laptop — Typical laptop in active use draws ~50 W (class range 20–100 W depending on load). Pending verification.
• gaming_pc — A mid-to-high gaming desktop under game load draws ~350 W including monitor excluded (class range 200–600 W). Pending measured verification.
• game_console — Current-generation consoles draw ~160 W while gaming (class range 70–220 W). Pending measured verification.
• wifi_router — Home Wi-Fi routers draw ~8 W continuously (class range 5–20 W). Pending verification.
• smart_speaker — Smart speakers idle/play at ~3 W (class range 1.5–6 W). Pending measured verification.
• e_bike — A ~0.5 kWh e-bike battery delivers ~45 km of assisted riding ≈ 0.011 kWh/km including charging losses. Pending measured verification.