LED bulbs use 75% less energy than incandescent bulbs — DOE
    Turning off lights when leaving saves $30-50/year per household — ENERGY STAR
    Standby power ('vampire load') can account for 5-10% of home energy use — DOE
    ENERGY STAR certified TVs use 25% less energy than standard models
    Programmable thermostats can save about 10% on heating/cooling — DOE
    Sealing air leaks can save 10-20% on heating and cooling costs — ENERGY STAR
    Heat pumps can reduce heating energy use by 50% vs. electric resistance — DOE
    Ceiling fans allow you to raise AC settings 4°F with no comfort loss — DOE
    Heating water accounts for about 18% of home energy use — DOE
    Low-flow showerheads save 2,700 gallons/year for a family of four — EPA
    Washing clothes in cold water can save $60+/year on water heating — ENERGY STAR
    Fixing a leaky faucet can save 3,000+ gallons/year — EPA
    ENERGY STAR refrigerators use 9% less energy than standard models
    Clean refrigerator coils annually for optimal efficiency — DOE
    Air-drying dishes instead of heat-dry saves 15-50% on dishwasher energy — DOE
    Proper attic insulation can cut heating/cooling costs by 15% — ENERGY STAR
    Windows can account for 25-30% of home heating/cooling energy use — DOE
    Window film can reduce solar heat gain by up to 70% — DOE
    Average US home solar system offsets 3-4 tons of CO₂ annually — EPA
    Solar panel costs have dropped 70%+ over the past decade — SEIA
    EVs cost about 60% less to fuel than gas vehicles — DOE
    Proper tire inflation improves gas mileage by 0.6% on average — DOE
    The average US household spends $2,000+/year on energy — EIA
    ENERGY STAR products have saved Americans $500 billion on energy bills
    LED bulbs use 75% less energy than incandescent bulbs — DOE
    Turning off lights when leaving saves $30-50/year per household — ENERGY STAR
    Standby power ('vampire load') can account for 5-10% of home energy use — DOE
    ENERGY STAR certified TVs use 25% less energy than standard models
    Programmable thermostats can save about 10% on heating/cooling — DOE
    Sealing air leaks can save 10-20% on heating and cooling costs — ENERGY STAR
    Heat pumps can reduce heating energy use by 50% vs. electric resistance — DOE
    Ceiling fans allow you to raise AC settings 4°F with no comfort loss — DOE
    Heating water accounts for about 18% of home energy use — DOE
    Low-flow showerheads save 2,700 gallons/year for a family of four — EPA
    Washing clothes in cold water can save $60+/year on water heating — ENERGY STAR
    Fixing a leaky faucet can save 3,000+ gallons/year — EPA
    ENERGY STAR refrigerators use 9% less energy than standard models
    Clean refrigerator coils annually for optimal efficiency — DOE
    Air-drying dishes instead of heat-dry saves 15-50% on dishwasher energy — DOE
    Proper attic insulation can cut heating/cooling costs by 15% — ENERGY STAR
    Windows can account for 25-30% of home heating/cooling energy use — DOE
    Window film can reduce solar heat gain by up to 70% — DOE
    Average US home solar system offsets 3-4 tons of CO₂ annually — EPA
    Solar panel costs have dropped 70%+ over the past decade — SEIA
    EVs cost about 60% less to fuel than gas vehicles — DOE
    Proper tire inflation improves gas mileage by 0.6% on average — DOE
    The average US household spends $2,000+/year on energy — EIA
    ENERGY STAR products have saved Americans $500 billion on energy bills
    LED bulbs use 75% less energy than incandescent bulbs — DOE
    Turning off lights when leaving saves $30-50/year per household — ENERGY STAR
    Standby power ('vampire load') can account for 5-10% of home energy use — DOE
    ENERGY STAR certified TVs use 25% less energy than standard models
    Programmable thermostats can save about 10% on heating/cooling — DOE
    Sealing air leaks can save 10-20% on heating and cooling costs — ENERGY STAR
    Heat pumps can reduce heating energy use by 50% vs. electric resistance — DOE
    Ceiling fans allow you to raise AC settings 4°F with no comfort loss — DOE
    Heating water accounts for about 18% of home energy use — DOE
    Low-flow showerheads save 2,700 gallons/year for a family of four — EPA
    Washing clothes in cold water can save $60+/year on water heating — ENERGY STAR
    Fixing a leaky faucet can save 3,000+ gallons/year — EPA
    ENERGY STAR refrigerators use 9% less energy than standard models
    Clean refrigerator coils annually for optimal efficiency — DOE
    Air-drying dishes instead of heat-dry saves 15-50% on dishwasher energy — DOE
    Proper attic insulation can cut heating/cooling costs by 15% — ENERGY STAR
    Windows can account for 25-30% of home heating/cooling energy use — DOE
    Window film can reduce solar heat gain by up to 70% — DOE
    Average US home solar system offsets 3-4 tons of CO₂ annually — EPA
    Solar panel costs have dropped 70%+ over the past decade — SEIA
    EVs cost about 60% less to fuel than gas vehicles — DOE
    Proper tire inflation improves gas mileage by 0.6% on average — DOE
    The average US household spends $2,000+/year on energy — EIA
    ENERGY STAR products have saved Americans $500 billion on energy bills
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    Advanced LightingEnergyBS

    Bulb Guide: A19, E26, BR30? Decoding Light Bulb Shapes

    Don't stare at the hardware store shelf in confusion. Here is the visual guide to the shapes (A, BR, PAR) and bases (E12, E26, GU10) of modern lighting.

    2 min read
    EnergyBS Research

    The Code: Letter + Number

    All light bulbs follow a code: Letter (Shape) + Number (Size). The number usually represents the diameter in 1/8ths of an inch.

    Part 1: The Shapes

    A-Series (Arbitrary) - "The Classic"

    • A19: The standard snow-cone shape you drew as a kid. Fits table lamps, ceiling fixtures, and fans.
    • Beam: Omni-directional (light goes everywhere).

    BR-Series (Bulged Reflector) - "The Flood"

    • BR30: The standard "Can light" bulb for recessed ceiling lights (4-6 inch cans).
    • BR40: The big fat one for larger cans.
    • Beam: Wide flood. Soft edges. Ideal for general room lighting from the ceiling.

    PAR-Series (Parabolic Aluminized Reflector) - "The Spotlight"

    • PAR20 / PAR30 / PAR38: Heavy glass, weather-resistant.
    • Beam: Sharp, focused spot or narrow flood.
    • Use: Outdoor security lights, track lighting, highlighting art.
    • Tip: Don't put these in general recessed cans unless you want "pools" of light on the floor.

    C-Series (Candelabra)

    • B10 / C7: The pointy flame shape.
    • Use: Chandeliers.

    Part 2: The Bases

    E-Series (Edison Screw)

    This is the screw thread.

    • E26 (Medium Base): The standard US light bulb screw. (A19s, BR30s).
    • E12 (Candelabra): The skinny screw for chandeliers.
    • E39 (Mogul): Giant industrial screw (Street lights).

    Pin Bases

    • GU10: The "twist and lock" with two fat pins. Common in track lighting and IKEA fixtures.
    • GU24: The two "posts" that twist. Mandated in some California fixtures to prevent using incandescent bulbs.

    Cheat Sheet

    1. Table Lamp: Buy A19 E26.
    2. Recessed Ceiling Can: Buy BR30 E26.
    3. Outdoor Flood: Buy PAR38 E26.
    4. Chandelier: Buy B10 E12.

    Memorize these 4, and you solve 95% of lighting confusion.

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