What is ton of refrigeration?

A ton of refrigeration is a power unit measuring the heat removal capacity of cooling systems, equal to 12,000 BTU per hour. It is the standard capacity rating for commercial and industrial air conditioning units in the United States.

Real-world uses

The ton of refrigeration (TR) is used for rating commercial and industrial cooling systems, chillers, and large-scale HVAC equipment. A small commercial building might need a 20–100 TR chiller. Data centres measure cooling capacity in TR. One TR = 12,000 BTU/h = approximately 3.517 kW.

History

The ton of refrigeration originated in the 19th century ice trade, when mechanical refrigeration systems were judged by their ability to replace ice delivery. One ton was defined as the cooling equivalent of melting one ton of ice per day. As mechanical refrigeration displaced natural ice by the early 20th century, TR became a standard industrial cooling unit.

Common mistakes

Confusing refrigeration tons with metric tons of mass—they are completely unrelated. Also, the "ton" in TR originated from the cooling power needed to melt one short ton (2,000 lb) of ice in 24 hours, not from any mass being cooled.

What is kilowatt?

A kilowatt is a unit of power equal to 1,000 watts. It is commonly used to rate electric motors, heating systems, solar panels, EV chargers, and industrial equipment.

Real-world uses

Kilowatts are used for rating home electrical systems, electric vehicle charging speeds (Level 2 chargers: 7–22 kW), solar panel array output, electric motors in appliances, and small generators. A typical household may have a peak demand of 3–10 kW.

History

As electricity supply systems expanded in the late 19th century, the kilowatt became the practical unit for measuring power demands and generation capacities beyond the range of single watts. Its adoption enabled standardised rating of motors, generators, and electrical infrastructure.

Common mistakes

Confusing kilowatts (kW, power) with kilowatt-hours (kWh, energy). A 7 kW EV charger running for 2 hours delivers 14 kWh of energy. Also, mixing up kW and kVA in electrical specifications—kVA is apparent power, not real power.

When is this conversion used?

Converting between ton of refrigeration and kilowatt is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region.

Worked examples

1 ton of refrigeration = 3.51685284 kilowatt

1 kilowatt = 1,000 watt

How to convert ton of refrigeration to kilowatt

To convert ton of refrigeration to kilowatt, multiply the value by 3.51685284.

To convert kilowatt back to ton of refrigeration, multiply by 0.28434514.

Measurement standards

The watt is the SI derived unit of power, defined as one joule per second (kg·m²/s³). Horsepower remains in widespread informal use, particularly in the automotive industry, but has no single universal definition across regions.

Did you know?

The human body at rest produces about 80 watts of power — roughly enough to keep an incandescent light bulb glowing. During intense exercise, a trained cyclist can sustain over 400 watts, and elite sprinters briefly exceed 2,000 watts.

Quick reference: ton of refrigeration to kilowatt

ton of refrigerationkilowatt
0.10.35168528
0.51.75842642
13.51685284
27.03370568
517.5842642
1035.1685284
2587.921321
50175.842642
100351.685284
250879.21321
5001,758.42642
1,0003,516.85284

Common values

ton of refrigerationkilowatt
LED light bulb0.00284345 ton of refrigeration0.01 kilowatt
Desktop computer0.08530354 ton of refrigeration0.3 kilowatt
Microwave oven0.28434514 ton of refrigeration1 kilowatt
Small car engine21.32588522 ton of refrigeration75 kilowatt
Wind turbine (large)853.03540878 ton of refrigeration3,000 kilowatt