Annual: efficienc y over the annual operation of the unit in heat pump
mode.
AdaptiveFunction Plu s, with the "Econom y" function, enables the
chiller assembl y to operate energy-saving programmes whilst still
providing the required level of c omfort.
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
The Uni versity of Padua has developed the s eas onal efficienc y index ESEER+, which takes the adaptation of the chiller set-points to different partial
load c onditions into acc ount. T his, therefore, c haracterises the s eas onal behavi our of the c hiller with AdaptiveFunction Plus compared to the more
traditional ESEER index.
The ESEER+ index c an therefor e be us ed for a quick eval uati on of s easonal energy c onsumption of units with AdaptiveFunction Plu s, ins tead of more
complex anal ys es conducted on the plant-sys tem which are usually difficult to complete.
Simplified method for calculating energy saving with AdaptiveFunction Plus
The dynamic anal ys es us ed to c alculate the energy c onsumption of chillers in a building/s ystem are generally too el aborate to be used for a quic k
comparison of different refrigerant units, inas muc h as they require a range of data that is not always available.
For a quic k esti mate of what the energy s avings could be with a unit equipped with Adapti veFunction Pl us software c ompared to a machine with
traditional control, we suggest using a si mplified method bas ed on the followi ng formulae:
E
N
C
ESEER+
Therefore in two units at the s ame nominal c ooling capacity and the s ame number of worki ng hours but equipped with different controls, the higher the
absorbed power the lower the seasonal efficienc y. In order to si mplify matters, here is an example c omparing a traditional c ontr ol Rhoss unit to one with
Adapti ve F uncti on Plus control:
Example:
Model TCHEY 240 equipped with traditi onal c ontrol s ystem:
Nominal cooling c apacity 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 s avings of a mac hine equipped with AdaptiveFunction Plu s software with respect to traditional s oftware is 11% .
5
6
7
8
9
10
11
12
X
power absorbed by c hiller equipped with Adapti veFunction Pl us software ( kWh)
number of c hiller operating hours
nominal c ooling capacity of the chiller (kW)
average s easonal efficienc y of chiller equi pped with Adapti ve Function Plus software
E
power absorbed by c hiller equipped with Adapti veFunction Pl us software ( kWh)
N
number of c hiller operating hours
C
nominal c ooling capacity of the chiller (kW)
ESEER
(European seas onal EER) European average s eas onal energy efficienc y
= 4.400,5 kW /h
X
Year divi ded into months (1 Januar y, 2 F ebruary, etc .).
Y
Energy efficienc y kWh s upplied / kWh absor bed.
Unit with fi xed set-point
Unit with sliding set- point
Analysis perfor med by c omparing the operation of a Y-Flow heat pump
unit with AdaptiveFunction Plus that operates with a fixed set-point
(7°C in the s ummer and 45°C in the winter) or with a slidi ng s et-point
(range betw een 7 and 14 °C i n the s ummer, range betw een 35 and
45°C in the winter) for an office building in Milan.
0,54 x N x C
E=
ESEER+
0,54 x N x C
E=
ESEER
Model TCHEY 240 equipped with control software AdaptiveFunction Plus:
Nominal cooling c apacity 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