Structural Design of the mCCHP-RES System - Design for Micro-Combined Cooling, Heating and Power Systems - page 192

Fig. 18 Determination of
height h ′ R (schematic
diagram)

Room index is:

a R b R

k ¼ ð 49 Þ

h 0 R ð a R þ b R Þ

If the calculation results in a room index of less than 0.6, a value of k = 0.6 shall be
used for simpli ed calculations,

where:

a R is the depth of the space;

b R is the width of the space;

h 0 R is the difference between the height of the lighting level and the work plane

(see Fig. 18 ).

5.3.3 Simplified Procedure

The speci c electrical power can be calculated with equation:

k A E m

m 2 p j ¼ W = ð 50 Þ

MF g s g LB g R

where:
p j is the electrical power in relation to the floor area for arti cial lighting;

k A is the reduction factor to take into account the task area;

MF is the maintenance factor which takes into account system aging processes up

to the time of the next maintenance (MF ) standard value

MF = 0.67 shall be assumed. Value 0.80 choose whether if lamps with only a
slight decrease in luminous

2ð 0 : 5 0 : 8 Þ

flux and a low failure rate and if the lamps used
have a pronounced decrease in luminous

flux and a high failure rate, the
maintenance factor shall be reduced to a value up to 0.50;

g s is the luminous ef cacy of the light source and the associated operating

devices used;

g LB is the light output ratio (luminaire ef ciency) of the type of luminaire used;

g R is the utilization factor given in the Table 28 .