Hitecsa EWNLM 115 Manuel D'utilisation page 24

Annual: efficiency over the annual operation of the unit in heat pump
mode.
AdaptiveFunction Plus, with the "Economy" function, enables the
chiller assembly to operate energy-saving programmes whilst still
providing the required level of comfort.
Y
6,0
5,5
5,0
4,5
4,0
3,5
3,0
2,5
2,0
1
2
3
4
The Seasonal Efficiency Index PLUS
HITECSA has developed the seasonal efficiency index ESEER+, which takes the adaptation of the chiller set-points to different partial load conditions
into account. This, therefore, characterises the seasonal behaviour of the chiller with AdaptiveFunction Plus compared to the more traditional
ESEER index.
The ESEER+ index can therefore be used for a quick evaluation of seasonal energy consumption of units with AdaptiveFunction Plus, instead of more
complex analyses conducted on the plant-system which are usually difficult to complete.
Simplified method for calculating energy saving with AdaptiveFunction Plus
The dynamic analyses used to calculate the energy consumption of chillers in a building/system are generally too elaborate to be used for a quick
comparison of different refrigerant units, inasmuch as they require a range of data that is not always available.
For a quick estimate of what the energy savings could be with a unit equipped with AdaptiveFunction Plus software compared to a machine with
traditional control, we suggest using a simplified method based on the following formulae:
E
N
C
ESEER+
E
N
C
ESEER
Therefore in two units at the same nominal cooling capacity and the same number of working hours but equipped with different controls, the higher the
absorbed power the lower the seasonal efficiency. In order to simplify matters, here is an example comparing a traditional control HITECSA unit to one
with Adaptive Function Plus control:
Example:
Model EWNLM 240 equipped with traditional control system:
Nominal cooling capacity of chiller = 41.9 kW
N = 8 hours/day x (5 months x 30 days/month) = 1200 hours
ESEER = 6.17
0.54 x 1200 x 41.9
E=
6,17
Therefore, the energy savings of a machine equipped with AdaptiveFunction Plus software with respect to traditional software is 11%.
5
6 7
8
9
10
11
12
X
power absorbed by chiller equipped with AdaptiveFunction Plus software (kWh)
number of chiller operating hours
nominal cooling capacity of the chiller (kW)
average seasonal efficiency of chiller equipped with Adaptive Function Plus software
power absorbed by chiller equipped with AdaptiveFunction Plus software (kWh)
number of chiller operating hours
nominal cooling capacity of the chiller (kW)
(European seasonal EER) European average seasonal energy efficiency
= 4.400,5 kW/h
X Year divided into months (1 January, 2 February, etc.).
Y Energy efficiency kWh supplied / kWh absorbed.
Unit with fixed set-point
Unit with sliding set-point
Analysis performed by comparing the operation of a Y-Flow heat pump
unit with AdaptiveFunction Plus that operates with a fixed set-point
(7°C in the summer and 45°C in the winter) or with a sliding set-point
(range between 7 and 14 °C in the summer, range between 35 and
45°C in the winter) for an office building in Barcelona.
0,54 x N x C
E=
ESEER+
0,54 x N x C
E=
ESEER
Model EWNLM 240 equipped with control software AdaptiveFunction Plus:
Nominal cooling capacity of chiller = 41.9 kW
N = 8 hours/day x (5 months x 30 days/month) = 1200 hours
ESEER+ = 6.91
0.54 x 1200 x 41.9
E=
25
= 3,929.3 kW/h
6,91
SECTION I: USER