How much electricity does a portable AC use?

A big factor in picking the right air conditioning system for you is the cost of running that system. Before you land on choosing a portable AC, it’s a good idea to know how much electricity a portable air conditioner uses. 

How much electricity does a portable AC use?

A portable AC uses 900 – 1400 watts of electricity an hour or .9 – 1.4 kWh. That’s fairly similar if not slightly higher than other kinds of air conditioning.

But not all portable ACs are the same. There’s a direct relationship between the cooling capacity of a portable air conditioner in BTUs and its hourly electricity use.

BTUs or British Thermal Units are a measure of heat energy. One BTU is the amount of energy needed to change the temperature of a kilo of water by 1 degree Fahrenheit. A typical portable AC has 5,000 – 8,000 BTUs of cooling capacity.

Since watts are a unit of energy and BTUs are a unit of energy, there’s actually a pretty simple conversion between the cooling capacity of an AC unit and the amount of electricity it consumes. 1 BTU is equivalent to .293 watts.

But different portable ACs with the same BTU rating can consume different amounts of electricity. And, a 10,000 BTU portable air conditioner will consume more electricity than an equivalent in-wall air conditioner.

So what’s going on here? The answer is energy efficiency. All portable air conditioners will waste some electricity when cooling your home’s air. Some of this energy is lost to heat, fans, and moving refrigerant around the system.

What are the electricity costs of portable AC?

The electricity costs of a portable AC are $0.13 – $0.36 per hour. That’s equivalent to $23.40 – $65.52 to run for 6 hours a day for a month. 

We calculated those numbers by taking the normal electricity consumption of .9 – 1.4 kWh an hour and adjusting it by a wide range of current US electricity costs: $0.13 – $0.26 per kWh. 

A portable air conditioner typically consumes between 900 to 1,400 watts of electricity per hour of operation. To put this into perspective, running a 1,200-watt portable AC for one hour would use 1.2 kilowatt-hours (kWh) of electricity. Given varying electricity rates across different regions, the cost can significantly differ. For instance, at an average electricity rate of $0.15 per kWh (a common rate in many parts of the United States), operating this AC unit for one hour would cost $0.18.

Monthly and Seasonal Costs

To estimate monthly costs, consider the duration of AC use per day. If you run a 1,200-watt portable AC for 6 hours daily, the daily electricity usage would be 7.2 kWh, costing approximately $1.08 per day. Over a month, this usage translates to 216 kWh and a cost of about $32.40 at the $0.15 per kWh rate.

Seasonal costs can be projected by multiplying monthly costs by the number of months the AC is in use. For a typical cooling season of 4 months, the total cost would be around $129.60 for the scenario above.

Factors Affecting Cost

Several factors can influence these costs:

• Electricity Rates: Your local utility company’s rates per kWh can vary widely by region and time of use, affecting overall costs.
• AC Efficiency: Units with higher Energy Efficiency Ratios (EER) consume less electricity for the same cooling effect, leading to lower costs.
• Usage Patterns: How frequently and at what settings you use your AC (e.g., temperature set point, fan speed) can significantly impact electricity consumption.
• Climate and Room Conditions: Hotter climates and poorly insulated rooms require more from your AC, increasing energy use and costs.
• Maintenance: Regular maintenance, such as cleaning filters, ensures your AC runs efficiently, keeping costs down.

Reducing Costs

To minimize electricity costs while using a portable AC:

• Opt for a model with a high EER or ENERGY STAR certification.
• Use programmable timers or smart AC controllers to run the AC only when needed.
• Maintain an optimal temperature setting; every degree lower can significantly increase energy consumption.
• Ensure good room insulation and use curtains or blinds to reduce heat gain from the sun.

Understanding these factors and taking proactive steps can help manage the electricity costs of your portable AC, ensuring comfort without undue expense.

Energy Efficiency Comparison of Cooling Systems

When selecting a cooling solution, energy efficiency is a critical factor affecting both operational costs and environmental impact. Here’s a streamlined comparison focusing on the efficiency aspects of portable air conditioners versus other cooling systems:

Portable Air Conditioners

• Efficiency: Generally lower than fixed systems due to less efficient heat exchange and potential energy loss from the exhaust system.
• Best for: Temporary setups or where installation of permanent units isn’t feasible, despite slightly higher energy costs.

Window Air Conditioners

• Efficiency: Typically more efficient than portable units due to better insulation and a direct exchange of air with the outside.
• Best for: Small to medium-sized rooms where window installation is possible, offering a good balance of cooling efficiency and cost.

Central Air Conditioning

• Efficiency: High overall efficiency, especially in models with advanced features like variable speed fans and multi-stage compressors.
• Best for: Whole-house cooling where ductwork exists, offering the most efficient cooling solution for larger homes despite the high upfront cost.

Ductless Mini-Split Systems

• Efficiency: Very high due to no ductwork losses and the ability for zoned cooling, which reduces unnecessary cooling of unoccupied spaces.
• Best for: Homes without existing ductwork, offering efficient cooling (and heating) with minimal aesthetic impact.

Evaporative Coolers

• Efficiency: Extremely energy-efficient in suitable dry climates, using the natural process of evaporation for cooling.
• Best for: Arid regions where the added humidity is beneficial, providing an eco-friendly and cost-effective cooling option.

Choosing for Efficiency

The most energy-efficient cooling option depends on your specific needs, including the climate, the area to be cooled, and installation possibilities. Portable ACs offer convenience at a slightly higher energy cost, making them suitable for specific situations like rentals or non-permanent installations. In contrast, systems like ductless mini-splits and central air conditioners, while more costly upfront, provide superior efficiency for long-term use.

Frequently Asked Questions About Portable ACs and Electricity Use

Q1: How can I calculate the energy cost of running a portable AC?

A1: To calculate the energy cost, multiply the unit’s wattage by the number of hours you use it daily, then divide by 1,000 to convert to kWh. Multiply this by your local electricity rate (per kWh) to find the daily cost. For example, a 1,200-watt unit running for 5 hours at $0.15 per kWh would cost $0.90 per day.

Q2: Can the energy efficiency of a portable AC change over time?

A2: Yes, the efficiency of a portable AC can decrease due to factors like dust accumulation, wear and tear, and lack of maintenance. Regular cleaning of filters and servicing can help maintain its efficiency.

Q3: Are there energy-efficient portable AC models available?

A3: Yes, look for models with a higher Energy Efficiency Ratio (EER) or those certified by ENERGY STAR as energy-efficient. These models use less electricity for the same cooling capacity.

Q4: How does room size affect a portable AC’s electricity use?

A4: Larger rooms require more cooling power, leading to higher electricity use. It’s essential to choose a portable AC with a suitable BTU rating for your room size to ensure efficient operation.

Q5: Does outside temperature affect how much electricity a portable AC uses?

A5: Yes, extremely hot days make the AC work harder to cool a room, increasing electricity consumption. Using curtains or blinds to reduce solar heat gain can help reduce this effect.

Q6: Can I reduce the electricity usage of my portable AC?

A6: Yes, by increasing the thermostat setting by a few degrees, using a fan to circulate cool air, ensuring the room is well-insulated, and keeping the AC’s filters clean, you can reduce energy use.

Q7: Is it more energy-efficient to keep the portable AC running all day or turn it on and off as needed?

A7: It’s generally more efficient to turn the AC off when not needed. However, using a programmable thermostat or timer to control its operation can optimize efficiency and comfort.

Q8: How do I know if my portable AC is using too much electricity?

A8: Compare your electricity bills before and after you start using the AC. A significant increase may indicate that the unit is inefficient or not operating correctly. Consider having it serviced or looking into more energy-efficient models.