Inverter Air Conditioner: What It Means and How to Choose by Electricity Use

An inverter AC changes the compressor’s speed as needed. In the old On/Off AC, the compressor always ran at full power, switched off when it reached the temperature and switched on again when the room warmed up.

This is how Tadiran’s AC guide describes it:

• On/Off: the compressor switches on and off alternately. This creates temperature swings, high electricity use and wear.
• Inverter: the compressor runs continuously and adjusts its output to the load. When the room reaches the set temperature, the AC keeps running at low output and doesn’t switch off.

The advantages per Tadiran: electricity savings, quieter operation, less wear and greater thermal comfort. Tadiran also writes that “it is commonly said” that an inverter saves up to 50% of electricity costs compared with old On/Off ACs, but doesn’t cite a source for the figure.

Inverter technology was developed in the early 1980s, and per Tadiran, international regulation pushed On/Off ACs out of the major markets, including Israel from July 2025. So all the wall-mounted ACs we saw on store lists are inverters. Tornado also states on its site that it sells only inverter ACs. Per Tadiran, mini-central and multi-inverter systems work on the same principle.

On every product page, look for four figures: cooling output and its range, SEER, SCOP and running current. They tell you far more than the word “inverter”.

What each figure means, with examples from the spec sheets we checked:

• BTU range: the Tadiran Solo 140 INV lists ⁦8,530 BTU⁩ nominal, in a range of ⁦2,390–⁦10,230 BTU⁩⁩. The Electra Platinum INV 250 lists ⁦18,500 BTU⁩, in a range of ⁦5,000–⁦21,400 BTU⁩⁩. The lower end determines how low the AC drops when the room is already cool, and the upper end how much it can deliver in a heat wave (sharav).
• SEER: seasonal cooling efficiency. On the models we checked we saw 5.5 on the Mitsubishi SRK25ZSP up to 7.3 on the Electra Platinum INV 150 and 250.
• SCOP: seasonal heating efficiency. We saw 3.8 on the Tadiran Air One INV 140 up to 5.3 on the Electra A Inverter 390.
• Running current: in an inverter AC it varies. The Tadiran Air One INV 340 lists 12 amps nominal, in a range of ⁦1.6–13.9⁩ amps. The maximum current determines the breaker.

Two common traps: some stores show COP, efficiency at one moment, instead of SEER, and you can’t compare the two. And some pages show two energy ratings, e.g. A++ in the specs and A in the table. In such cases, trust the numbers, not the letter. The full definitions are in Tadiran’s glossary.

At full output, a 1 HP AC draws about ⁦0.85 kW⁩, which costs about 54 agorot per hour. A 2 HP AC at full output draws up to about ⁦2.3 kW⁩, i.e. up to about ₪1.5 per hour. An inverter runs below that most of the time. (In Israel, AC size is given in “horsepower”, where 1 HP ≈ ⁦9,000 BTU⁩/h.)

The calculation is based on the residential rate from July 1, 2026: 53.83 agorot per kWh before VAT, and 63.52 agorot including VAT.

• 1 HP: per the Electra Relax Inverter 140 spec sheet, cooling consumption is 850 watts. 0.85 × 63.52 = about 54 agorot per hour at full output.
• 2 HP: the Tadiran Air One INV 240 lists a current of 10 amps in cooling at 230 volts, i.e. up to about ⁦2.3 kW⁩ and up to about ₪1.5 per hour.

What does that come to per month? Suppose, for illustration, a 1 HP AC in a bedroom that runs 8 hours at night. If its average consumption is about half of full output, about ⁦0.4 kW⁩, the month will cost about ⁦96 kWh⁩, i.e. about ₪61. If insulation is weak or the room is under the roof, average consumption will be closer to full output, and the amount can reach about ₪130. This is an illustration, not a measurement. Models and prices by size are detailed in our 1 HP and 2 HP air conditioner guides.

What affects actual consumption: insulation, shade on the windows, the temperature you set, clean filters and SEER. An AC with SEER 7 uses about 15% less than one with SEER 6 for the same cooling.

Let it run continuously at a reasonable temperature, and don’t switch it off and on every hour. An inverter saves exactly when it runs for a long time at low output.

Practical recommendations, some from the importers:

• A reasonable temperature: Tornado recommends not routinely running it at 16°C (61°F) in summer or 30°C (86°F) in winter. That wears out the AC and raises electricity use.
• Don’t switch off when you go out for an hour: switching off and on sends the compressor back to full output to re-cool the whole room. If you’re out for a whole day, switch it off.
• Clean filters: Tadiran recommends cleaning the filter every 250 operating hours. A clogged filter reduces output and forces the fan to work harder. A full explanation is in our AC cleaning guide.
• A clear outdoor unit: per Tornado, blocking the outdoor unit increases the current.
• Sleep mode and ECO: some remotes have a saving mode that shifts the temperature by a few degrees. On Family’s remote, for example, ECO raises the temperature by 2 degrees in cooling. The explanations are in our Tadiran AC remote symbols guide.
• Shade and insulation: a closed shutter (tris) during sunny hours saves more than any button on the remote.

In winter, an inverter with a high SCOP is one of the most economical ways to heat a home. If you heat with the AC, choose by SCOP.

An inverter AC is a heat pump: in winter it moves heat from outside to inside. So it can deliver more heat than it consumes in electricity, and SCOP measures exactly that.

What this means in numbers: a SCOP of 4 means that on a seasonal average, the AC delivers about 4 units of heat per unit of electricity. On the models we checked we saw a wide range:

• High SCOP: the Electra A Inverter 390 at 5.3, the Electra Platinum INV 180 and 250 at 5.2, and the Electra Platinum INV 150 at 5.1.
• Medium SCOP: the Tadiran Alpha Pro INV 340N at 4.3, and the Tadiran Solo 140 and Tornado TOP J INV 16 at 4.1.
• Relatively low SCOP: the Tadiran Air One INV 140 and 340 at 3.8.

The difference between a SCOP of 3.8 and 5.2 is worth about 27% less electricity for the same heat. In a home heated by AC every evening in winter, that’s a noticeable difference on the bill.

Two things to know about heating with an inverter: on a cold day, the outdoor unit periodically goes into defrost. Per Tadiran this takes about 10 minutes, and per Tornado about ⁦10–15⁩ minutes. Also, check the heating output in BTU, not just cooling. On some models heating is much lower than cooling.

The feature that saves the most is basic efficiency, SEER and SCOP. Features like WiFi and AI help mainly if they change your habits.

What we saw in stores:

• WiFi and app: on almost every current model, even the cheap ones. It lets you switch off an AC you forgot on, or start it half an hour before you get home. Per the Tadiran Connect app manual, it also sends a filter-cleaning reminder after 250 operating hours.
• AI: the Electra AI INV 350, per the store page, includes a system that learns the room and the user’s habits, and shows savings claims of 20% vs a regular inverter and 70% vs On/Off. These are manufacturer claims, and we found no independent measurement.
• iFeel: the temperature is measured at the remote rather than at the AC, so the AC targets the spot where you’re sitting. This helps mainly in a large room.

On a limited budget, invest first in a high SEER and the right size. An undersized AC runs at full output all the time and cancels out the inverter’s advantage, and an oversized AC doesn’t save either. Choosing the size is explained in our guide on how many horsepower an AC needs.