Patio Heater Coverage & Running Cost Calculator

How many patio heaters does your seating area need, and what do they cost to run? Enter the size of the area you want to keep warm, how exposed it is, and your fuel. The calculator compares Bromic Smart-Heat electric and gas heaters side by side: how many you need and what they cost per hour and per month at your own energy prices.

How the calculator works

• Heat coverage: each heater's "up to" coverage comes from Bromic's published specifications, for example up to 130 sq ft for the Tungsten Electric 4000W or up to 215 sq ft for the Tungsten 500 gas heater.
• Wind and exposure: radiant heaters warm people and surfaces, not the air, but wind still carries heat away. For partly covered patios the calculator plans for 25% more area, and for open, windy patios 50% more.
• Running cost: electric = watts ÷ 1,000 × hours × price per kWh. Natural gas = BTU per hour ÷ 100,000 (one therm) × price per therm. Propane = BTU per hour ÷ 91,500 (one gallon) × price per gallon.

Frequently asked questions

Are electric patio heaters expensive to run?

Usually less than people expect. A 4,000-watt electric heater uses 4 kWh per hour, which is about $0.72 per hour at $0.18 per kWh. Gas heaters put out more heat per unit and suit open, windy spaces, while electric heaters are silent, fume-free and ideal under a roof.

Electric or gas: which should I choose?

Electric radiant heaters work best on covered and partly covered patios, where they can be mounted close to the seating. Gas heaters deliver more output for open terraces and large areas. Read our full gas vs. electric patio heater guide.

Do infrared patio heaters work in winter?

Yes, radiant heat warms you directly even in cold air, as long as the heater is sized and positioned for the space. See do infrared patio heaters work in winter?

Not sure how to lay out your heaters? Request a free heating plan, or browse our electric patio heaters and gas patio heaters.