How much does it cost to run a outdoor electric patio heater?
An outdoor electric patio heater converts electrical energy directly into infrared radiation to warm people and objects in your outdoor seating area, rather than heating the air itself. Because they operate at high wattage to overcome heat loss in open environments and must produce sufficient radiant intensity to be felt at a distance, they consume considerably more power than indoor heating appliances.
Outdoor Electric Patio Heater running cost calculator
- Per day
- $1.02
- Per month
- $10.20
- Per year
- $122.40
- CO₂ / year
- 288 kg
Based on 720 kWh per year. Adjust the price per kWh to match your latest electricity bill for an exact figure.
At 1500 watts used 4 hours a day, a outdoor electric patio heater costs about $1.02 per day, $10.20 per month and $122.40 per year on an average rate of 17¢ per kWh — roughly 720 kWh and 288 kg of CO₂ over a year. Enter your own electricity rate and usage in the calculator above for a figure matched to your bill.
Electric patio heaters work fundamentally differently from space heaters or furnaces—they emit infrared radiation that travels through air without warming it, then is absorbed by people, furniture, and surfaces nearby. This means they're essentially inefficient for heating large outdoor areas, since much of their output dissipates into the open sky and surrounding environment. The 1500W draw typical of residential models reflects the energy needed to heat resistive elements hot enough to generate sufficient radiant intensity to be noticeable from sitting distance. Unlike gas heaters that vent combustion byproducts, electric models convert nearly 100% of input electricity into heat, but that high wattage means they draw serious current during operation.
Seasonal and weather-dependent use patterns significantly affect real-world operating costs. Most owners use patio heaters during shoulder seasons (spring and fall) rather than year-round, typically on cooler evenings when outdoor entertaining would otherwise be uncomfortable. Wind is the silent cost driver—a breezy evening increases heat loss dramatically, often prompting users to run heaters longer or at higher intensities than on still nights. Similarly, cloud cover or temperature drops of just a few degrees can change perceived comfort enough to trigger extended use, making usage highly variable between seasons and regions.
The physical location and type of patio heater significantly influence how efficiently it warms your space. Mounting placement matters: wall-mounted or overhead units diffuse heat to a wider area but lose more to the sky, while freestanding pedestal heaters allow you to position them closer to seating areas, creating localized warmth zones. Reflectors or shields (if your model has them) redirect some radiant energy downward, effectively making the heater work harder for the same perceived benefit. Enclosed patios or those under pergolas retain heat better than completely open spaces, though most people don't factor this into purchase decisions.
When shopping for an electric patio heater, wattage and heat output ratings (usually measured in BTU per hour) tell only part of the story. Actual efficiency depends on design details: the quality and emissivity of the heating element, the geometry of the reflector, and whether the unit has adjustable power levels or thermostat controls. Models with switchable wattage (some offer 750W and 1500W settings) allow you to use lower power on mild evenings or in sheltered spots, meaningfully reducing seasonal consumption. Warranty and element durability matter too, since replacing a failed heating element or reflector can cost nearly as much as buying a lower-end heater.
One frequent mistake is treating patio heaters as whole-space heaters for large decks or patios. In reality, electric models are best suited to warming small seating areas with three to six people nearby, within roughly 10–15 feet of the unit. Running an oversized heater continuously to warm a sprawling deck wastes energy and frustrates users. Similarly, leaving heaters on longer than needed on mild evenings—simply out of habit rather than actual comfort need—drives up annual costs. If you frequently entertain outdoors across an extended season, you'll see the cost and energy impact in the figures above; if you use your patio heater sparingly on a handful of cool nights per year, the impact is modest by comparison.
Frequently asked questions
- Why do electric patio heaters draw so much power compared to indoor heaters?
- Outdoor heaters must overcome significant heat loss in an open environment where radiant energy dissipates upward and outward. They generate extremely hot resistive elements (often glowing red) to produce enough infrared intensity to be felt at a distance, whereas indoor space heaters can warm air in an enclosed room more efficiently. The high wattage is necessary to achieve usable warmth outdoors; lower-power models feel noticeably weak in real-world conditions.
- Can I reduce energy use by choosing a lower-wattage patio heater?
- Lower-wattage models (around 750–1000W) do exist and will reduce energy consumption, but they provide proportionally less heat output. They work best for small, sheltered seating areas or for mild weather when you only need supplemental warmth. For typical backyard entertaining on cool evenings, most people find a 1500W heater necessary for noticeable comfort, making the choice a trade-off between running a weaker heater longer versus a stronger heater for shorter periods.
- Does wind affect how much a patio heater costs to run?
- Yes, significantly. Wind disperses infrared radiation and increases convective heat loss, making the heater less effective. On windy evenings, you'll typically run the heater longer or feel the need to use it more frequently to maintain comfort. Sheltering your patio with screens, fencing, or landscaping can reduce wind's impact and lower effective operating time, even though the heater's wattage stays the same.
- Are there thermostat or auto-shutoff features that help save energy on electric patio heaters?
- Some higher-end models include adjustable power levels or timers, but true thermostat control is rare on outdoor heaters since outdoor temperature is a weak proxy for radiant heat comfort. Timers can prevent accidental all-night operation, and adjustable wattage lets you use lower power on mild evenings or in sheltered areas. Manual control with awareness of actual comfort needs is often the most effective way to avoid unnecessary runtime.
- How does covered versus uncovered patio seating affect heater runtime?
- A roof, pergola, or awning over your seating area helps retain some upward-radiated heat, making the heater feel more effective and reducing the time you need to run it. Completely open-air patios lose heat in all directions, requiring longer or more frequent heater use for the same comfort level. The benefit is most noticeable on calm, clear nights; on cloudy, windy evenings, the improvement is marginal.
- Should I leave my patio heater on between uses, or turn it off each time?
- Always turn it off when not actively using the seating area. Electric patio heaters have no residual benefit from warming the ground or air, so leaving them on unattended wastes energy entirely. Turning it on just before you use the patio and off when you're done is the most efficient approach, and it also extends the lifespan of the heating element.