Ignis Ventless Bio Ethanol Fireplace Circum Stainless Steel Ventless - no chimney, no gas or electric lines required. Eco-Friendly - doesn't produce any smoke, sooth or dangerous gases. Portable - Place it anywhere in your home. Capacity: 0.5 Liter. Approximate burn time - 2 hours per refill. Approximate BTU output - 2000.