Which is More Cost-Effective, Using a Low Watt AC or an Inverter AC? This Is What the Electrical Engineering Professor Says
Social media usersXCurrently, there is a lot of discussion comparing low watt AC and inverter AC in terms of cost and electrical efficiency.
This discussion started from the account’s upload@t********lOn Friday (10/17/2025), asking for recommendations for energy-efficient 1/2 HP air conditioners.
“I want to buy a 1/2 HP air conditioner that is low watt but cheap. My friend recommended this brand, do you have any other suggestions?she wrote.
The post immediately received many responses. Most netizens suggested choosing an inverter AC, which is considered more electricity-efficient even though it is slightly more expensive.
“Don’t believe in low watt, it’s better to directly choose an inverter AC. It is much more energy efficient and doesn’t waste electricity. For 1/2 PK, there are ones available for around Rp 3 million.,” wrote the account@K******n.
Then, which one is actually more electricity-efficient between low watt AC or inverter?
Experts: AC inverter is a more efficient choice
Electrical Engineering Lecturer of Sebelas Maret University (UNS) Solo, Muhammad Nizam, explained that AClow wattagebasically is a conventional air conditioner ornon-inverterwhich is designed to have lower power consumption compared to ordinary AC.
AClow watt,conventional, ornon-inverterdesigned to have lower power consumption compared to ACnon-inverter“Generally,” he explained, when asked for information,Wednesday (10/22/2025).
However, despite being more power-efficient, the operation of a low-watt AC is the same as other conventional ACs. In this case, the compressor will turn on and off alternately to maintain the room temperature.
Meanwhile, ACinverterEquipped with advanced compressor technology that can adjust the operating speed according to cooling needs.
According to Nizam, ACinverterMore suitable for regular and long-term use, whereas AClow wattageMore economical for infrequent use.
ACinverteris a more efficient and comfortable choice for intensive use, while AClow wattage“more economical for less frequent use,” he explained.
Difference in compressor operation
Like Nizam, Lecturer of the Electrical Engineering Study Program, Faculty of Engineering, State University of Yogyakarta (FT UNY), Toto Sukisno said that the main difference between these two types of AC lies in the compressor’s working system.
ACinverterItu the compressor is always on, adjusting to temperature needs, while AClow wattage“His compressor is on-off,” said Toto when contacted on Wednesday.
They added that the efficiency of both types of AC greatly depends on usage patterns.
AClow wattage“Suitable for short-term use in rooms that are frequently opened and closed due to its low initial power,” explained Toto.
Meanwhile, ACinverter“More energy-efficient for long-term use in enclosed spaces because the compressor works more efficiently with variable speed after the temperature is reached,” he added.