What is a Mini Split Heat Pump? Seasonal energy efficiency ratio.

For residential homes, some countries set minimum requirements for energy efficiency. In the United States, the efficiency of air conditioners is often (but not always) rated by the seasonal energy efficiency ratio (SEER). The higher the SEER rating, the more energy efficient is the air conditioner. The SEER rating is the BTU of cooling output during its normal annual usage divided by the total electric energy input in watt hours (W·h) during the same period. SEER = BTU ÷ (W·h) this can also be rewritten as: SEER = (BTU / h) ÷ W, where "W" is the average electrical power in Watts, and (BTU/h) is the rated cooling power.

Heat Pump Residential.  The Total Annual Cooling. 

For example, a 5000 BTU/h air-conditioning unit, with a SEER of 10, would consume 5000/10 = 500 Watts of power on average. The electrical energy consumed per year can be calculated as the average power multiplied by the annual operating time: 500 W × 1000 h = 500,000 W·h = 500 kWh.

 

Assuming 1000 hours of operation during a typical cooling season (i.e., 8 hours per day for 125 days per year). Another method that yields the same result, is to calculate the total annual cooling output: 5000 BTU/h × 1000 h = 5,000,000 BTU

Then, for a SEER of 10, the annual electrical energy usage would be:

5,000,000 BTU ÷ 10 = 500,000 W·h = 500 kWh.

Heat Pump for Cooling. The Coefficient of Performance (COP).

SEER is related to the coefficient of performance (COP) commonly used in thermodynamics and also to the Energy Efficiency Ratio (EER). The EER is the efficiency rating for the equipment at a particular pair of external and internal temperatures, while SEER is calculated over a whole range of external temperatures (i.e., the temperature distribution for the geographical location of the SEER test). SEER is unusual in that it is composed of an Imperial unit divided by an SI unit. The COP is a ratio with the same metric units of energy (joules) in both the numerator and denominator. They cancel out, leaving a dimensionless quantity.

How Heat Pump Works. Formulas for the Approximate Conversion. 

Formulas for the approximate conversion between SEER and EER or COP are available from the Pacific Gas and Electric Company: (1)     SEER = EER ÷ 0.9, (2)     SEER = COP × 3.792, (3)     EER = COP × 3.413.

 

From equation (2) above, a SEER of 13 is equivalent to a COP of 3.43, which means that 3.43 units of heat energy are pumped per unit of work energy.

The United States now requires that residential systems manufactured in 2006 have a minimum SEER rating of 13 (although window-box systems are exempt from this law, so their SEER is still around 10).[18]