There are many
efficiency standards that are being used across the world for assessing the
efficiency of heat
pumps. Here are the most common ones focusing on heat pump units made in
the US and the EU –
Comparing The
Efficiencies Of Different Heat Pump Units
CoP or
Coefficient of Performance
The CoP is used
worldwide for both heating and cooling. It's simply the heating or cooling
output divided by the electricity input. It's not a good indicator of
efficiency. However, it only gives a snapshot of how a unit should perform
under very precise conditions. As the outside air temperature varies hourly and
daily, this is not a good indicator of efficiency.
SCOP or
Seasonal Coefficient of Performance
You'll see this
in European units to measure the average heating efficiency. It's a much better
indicator than the CoP. The manufacturer has to test the performance of their
units at different outside air temperatures. The unit is expected to operate at
a specified number of hours at each temperature per year, depending on location
in Europe.
There are three zones: warm, average and cold. The heat supplied and electricity consumed for the specified operating hours at each temperature is accumulated and divided to give an average CoP for the year. The SCOP also considers the energy consumption for things such as standby mode. Typical SCOP values lie between 3.9 and 5.2 with a higher number meaning more efficient.
EER or Energy
Efficiency Ratio
This is a
measurement of the unit's cooling efficiency that's mostly used in the USA.
It's a ratio of a unit's cooling capacity and BTUs divided by the watts
consumed to produce it. This is only tested in one condition. Generally, 95
degrees Fahrenheit outside air temperature and inside return air temperature of
80 degrees Fahrenheit at 50 percent relative humidity. So it's not recommended
to use this to estimate your annual energy consumption or assess how the unit
will perform in your location; unless you live in a hot climate. However, it is
rated between 11 and 16 with a higher the number, the more efficient it
is.
SEER or Seasonal
Energy Efficiency Ratio
It is used in
both the US and the EU on units that operate in cooling mode. Manufacturers
will calculate their units SEER value by testing it at several different
outdoor temperatures to represent a cooling season. The units of measurement
are different from EU models calculated on cooling per watts of electricity and
US models calculated on BTUs of cooling per watts of electricity used in both
cases. This is suitable for units installed in very average climates. It's a
good way to compare different units. But not a good way to calculate the energy
consumption unless you live in an area with pretty average weather conditions.
Typically, you can find SEER values for US units between 14 and 24 and EU units
between 5.25 and 7.2. The higher the number, the more efficient the unit is
rated.
HSPF or Heating
Seasonal Performance Factor
This is
used in the US for the heating mode of air source heat pumps. It is the ratio
between heat output in BTU's over a heating season divided by how many
watt-hours of electricity we use to produce it. It also takes into account
supplementary electric heating. Manufacturers calculate the unit's HSPF by
testing at different temperatures to simulate a heating season. This is an
estimate of how the unit will perform and it may not actually perform like this
in reality, especially if the unit is oversized. It is a good way to compare
different units. Typically, the value of a unit will be between 7.7 and 14 with
a higher the number, the more efficient the unit is rated.
See the summary
here in this infographic – Different
Heat Pump Efficiency Standards – SEER, EER, HSPF, CoP & SCOP [Infographic]
Are you looking for an HVAC system for your home?
Check out Green
Leaf Air Shop where we have a wide range of residential & commercial
HVAC system including: – Trane 14 SEER HVAC Systems,
Trane 16 SEER
HVAC Systems, Trane
Two Stage 17 SEER HVAC Systems & Heat Pump
