Calculator · Thermal Engineering
Refrigerator & Heat-Pump COP
A reversible refrigerator and a reversible heat pump between the same two reservoirs differ only in which heat stream is the product. Pick the device, enter both absolute temperatures, and read the COP and the work a stated heat duty requires.
Inputs
Ideal cycle limits: reversible Carnot models between two reservoirs, and ideal air-standard Otto, Diesel and Brayton cycles with constant specific heats. Real machines fall below these values.
Results
COP
Reversible (Carnot) limit. Heat-pump COP = refrigerator COP + 1 for the same reservoirs.
| Heat lift Q_C | 100 kJ |
|---|---|
| Work input W | 18.519 kJ |
| Heat rejected Q_H | 118.52 kJ |
| Refrigerator COP | 5.4 |
| Heat-pump COP (same reservoirs) | 6.4 |
Assumptions
- · reversible cycle
- · two reservoirs
Explore in the Lab
The full cycle state travels; the Lab adds the state diagram and the comparison view.
Technical reference
COP_R = T_C / (T_H − T_C)
COP_HP = T_H / (T_H − T_C)
COP_HP = COP_R + 1
- T_H
- hot reservoir temperature (absolute)[K]
- T_C
- cold reservoir temperature (absolute)[K]
- r
- compression ratio[—]
- r_c
- cutoff ratio[—]
- r_p
- pressure ratio[—]
- γ
- heat-capacity ratio cp/cv[—]
Temperatures are absolute (kelvin); equal or inverted reservoirs are refused.
These are reversible ideal limits — every real device between the same reservoirs has a lower COP.