How many square feet does the Windmill 10W2Wi cool?

At 10,000 BTU/h it suits a room of about 350 to 450 sq ft with normal sun and two people, following the ENERGY STAR sizing guide. In a heavily shaded room that stretches to about 385-495 sq ft; in a very sunny one it shrinks to 315-405 sq ft. A kitchen needs 4,000 BTU more.

How many watts and amps does the Windmill 10W2Wi use?

About 667 watts at full power (10,000 BTU/h divided by its CEER of 15.0), which is 5.8 amps at 115 V. That is 0 W more than the typical unit in its class (667 W), or $0 a year cheaper to run at 18.0¢/kWh. Its inverter compressor slows down instead of cycling, so real use is usually lower. Its CEER beats 14% of the 28 units in the class.

Can the Windmill 10W2Wi run on a standard outlet?

Yes. It runs on 115 V and draws about 5.8 A, well inside a standard 15 A outlet, but do not share the circuit with a space heater, microwave or other big load. Every certified unit in this class is 115 V.

What are the dimensions of the Windmill 10W2Wi, and will it fit my window?

19.3" W × 13.3" H × 22.5" D, 63 lb. It is narrower than 63% of its 27 competitors and lighter than 44% of them. The window must be wider than 19.3"; the side panels fill the remaining gap.

Can the Windmill 10W2Wi also heat the room?

No, it only cools. If you also need heat, 6 certified units in this class can do both; see the list of air conditioners with heat.

Is the Windmill 10W2Wi worth buying to replace an old air conditioner?

An old unit of the same size at 9 CEER would cost about $150 a year to run at 750 hours and 18.0¢/kWh; this one costs about $90, so it saves roughly $60 a year.

10,000 BTU window air conditioner

Windmill 10W2Wi

Below average efficiency for its size: a CEER of 15.0 ranks #24 of 28 10,000 BTU window air conditioners.

It cools a room of about 350-450 sq ft, draws about 667 watts and costs about $90 a year to run at typical U.S. use and prices.

CEER: 15.0 Combined efficiency, higher is better
Below average · beats 36%
Cooling: 10,000 BTU/hFor about 350-450 sq ft
Energy use: 500 kWh/yr38% less than the federal minimum
Unit size: 19.3" wide 13.3" high, 22.5" deep, 63 lb

A good fit if…

You want to plug it into an ordinary outlet - it runs on 115 V.

Think twice if…

Running cost matters most - its CEER is below average for 10,000 BTU window air conditioners.
You also need heat - it cools only.

Calculate my running cost Check the size for my room

Details

Specifications10,000 BTU, 115 V

General
Brand	Windmill
Model number	10W2Wi
Type	Window
Design	Standard box
Heating	No, cooling only
Compressor	Variable speed (inverter)
Voltage	115 V (standard outlet)
Refrigerant	R-32 (GWP 675)
Support bracket included	Yes
On the market since	March 12, 2024
Last certified	March 28, 2024
Performance
Cooling capacity	10,000 BTU/h
CEERCombined energy efficiency ratio, includes standby power	15.0
Yearly energy useENERGY STAR test: 750 hours	500 kWh
Better than federal minimum	38% less energy
ENERGY STAR Most Efficient	No
Size
Width × height × depth	19.3" W × 13.3" H × 22.5" D
Weight	63 lb

How it compares with 27 other 10,000 BTU window units#24 of 28

CEER (class median 15.0)15.0, tied with 11 others
Yearly cost vs. class median ($90)about the same
Width 19.3" (class median 20.3")narrower than 63%
Weight 63 lb (class median 58 lb)lighter than 44%
Rank among 11 similar designs#10

Compared with the other ENERGY STAR certified 10,000 BTU window units. Yearly cost at 750 hours and 18.0¢/kWh.

Questions6

How many square feet does the Windmill 10W2Wi cool?: At 10,000 BTU/h it suits a room of about 350 to 450 sq ft with normal sun and two people, following the ENERGY STAR sizing guide. In a heavily shaded room that stretches to about 385-495 sq ft; in a very sunny one it shrinks to 315-405 sq ft. A kitchen needs 4,000 BTU more.
How many watts and amps does the Windmill 10W2Wi use?: About 667 watts at full power (10,000 BTU/h divided by its CEER of 15.0), which is 5.8 amps at 115 V. That is 0 W more than the typical unit in its class (667 W), or $0 a year cheaper to run at 18.0¢/kWh. Its inverter compressor slows down instead of cycling, so real use is usually lower. Its CEER beats 14% of the 28 units in the class.
Can the Windmill 10W2Wi run on a standard outlet?: Yes. It runs on 115 V and draws about 5.8 A, well inside a standard 15 A outlet, but do not share the circuit with a space heater, microwave or other big load. Every certified unit in this class is 115 V.
What are the dimensions of the Windmill 10W2Wi, and will it fit my window?: 19.3" W × 13.3" H × 22.5" D, 63 lb. It is narrower than 63% of its 27 competitors and lighter than 44% of them. The window must be wider than 19.3"; the side panels fill the remaining gap.
Can the Windmill 10W2Wi also heat the room?: No, it only cools. If you also need heat, 6 certified units in this class can do both; see the list of air conditioners with heat.
Is the Windmill 10W2Wi worth buying to replace an old air conditioner?: An old unit of the same size at 9 CEER would cost about $150 a year to run at 750 hours and 18.0¢/kWh; this one costs about $90, so it saves roughly $60 a year.

Running cost calculator

Pre-filled with this model. Pick your state and how many hours you run it, or see the yearly cost in every state.

1. The air conditioner Windmill 10W2Wi

Cooling capacity BTU/hCEER efficiency, higher is better

2. How you use it

StateElectricity ¢ per kWhHours a day at full powerDays a year from your state's climate

Per year: $141
Per month of use: $26
Per day: $0.85
Per hour: 10.7¢
Power draw: 667 W

Electricity used: 880 kWh a yearAn old 9 CEER unit of the same size would cost $235

Power draw is capacity divided by CEER, which already includes standby power. Inverter units often run below full power, so real use can be lower. Electricity prices: U.S. EIA residential averages (12 months to July 2026). Days a year start from your state's cooling degree days (NOAA 1991-2020 normals).

Closest alternatives

Units with a similar CEER in the same class, and what sets each one apart from the Windmill 10W2Wi.

Model	CEER	Compared with this one
Midea MAW10V1QWT	15.0	same CEER, 10 lb lighter, U-shaped
LG LW1022FVSM	15.0	same CEER, saddle design
Hisense AWUS1026TW	15.0	same CEER, 1" wider, 8 lb lighter, U-shaped
TCL T10WQ2S	15.0	same CEER, 1.4" wider, 5 lb lighter, U-shaped
Midea MAW10V1UWT	15.0	same CEER, 9 lb lighter

See all 28 10,000 BTU window air conditioners, ranked

Source: ENERGY STAR Certified Room Air Conditioners (U.S. EPA), certification of March 28, 2024. How we use the data.