most efficient space heater

HEATDAZ Air Purifier for Bedroom, Air Purifiers for Home Bedroom, Quiet Air Cleaner with 24dB Sleep Mode, True HEPA Filter for Pet

GE Appliances Electronic Window Air Conditioner Unit

VOLTORB Freestanding Portable Electric Space Heater for Bedroom or Indoor Use with LED Display, Remote Control, and Fan Only Mode (3 Pack)

ZAFRO Electric Fireplace Heater 17" with Remote Control, Cathedral Stylish, Different Flame Effects and Log Set Colors, Adjustable Brightness , Beige

Comfort Glow® ES4195 The Sanford™ 1,500-Watt-Max Freestanding Electric Stove with Real Flame Look

2-in-1 Heater & Humidifier

TCL 5100 BTU SACC (8,500 BTU ASHRAE) Smart Portable Air Conditioner Fan & Dehumidifier (H5P44W): AC Unit for 100-300 sq. ft.

Gray HEATDAZ HEPA Air Purifier - Perfect Christmas Gift, 22dB Sleep Mode with Fragrance Sponge, 225 sqft Coverage

BLACK+DECKER™ 1,500-Watt-Max Personal Desktop Heater with Fan Setting in White

BLACK+DECKER™ 1,500-Watt-Max Personal Desktop Heater with Fan Setting in Black

Comfort Glow® QDE1250 1,500-Watt-Max Tabletop Infrared Quartz Heater with Thermostat and Remote, Black

Philips 3000 Series 7.6qt Air Fryer Black

Dan’s Originals for Lasko 2033622 Space Heater Remote Control - 2033622

Frigidaire Portable Neck Heater Black

ZAFRO Window Air Conditioner 8,000 BTU Powerful Cooling for 350 Sq Ft Rooms,Quiet Operation Window AC Unit 7 Modes&4 Speeds,ECO Mode,Washable Filter

Karl Home 1500-Watt Infrared Quartz Wood Cabinet Electric Space Heater

Cascade Portable Heater with Handle Black

EZ Heat Oscillating Parabolic Dish Heater, Powerful 1000W with Adjustable Tilt Design

Heat Storm A-1500-PHX-WIFI Infrared Heater Wi-Fi Wall Mounted White

Cascade Portable Heater with Handle Goldenrod

Cascade Portable Heater with Handle Dark Gray