Experimental Case Study - Design for Micro-Combined Cooling, Heating and Power Systems - page 361

Table 16 Calculated values for sizing the PVs
July
horizontal
solar
irradiation
(Wh/m 2 /d)

Sunshine
time
t sunlight
(h)

Speci cPV
production
e PV kWh = m TFA

Monthly energy
produced by the
PV panels
E PV max

Daily
produced by
the PV
panels
E PV day kWh

Power of
the PV
panels
P PV panel kW ð kWh Þ ðÞ

ð Þ

6,560

6.5 1.02 304.98 12.29 1.89

photovoltaic panel is established according to the power and voltage of both panel
and its modules. The number of modules installed, n SM = 10, has to be the whole
even number, superior to the number resulted from the relation 5 in Chap.
“ Functional Design of the mCCHP-RES System ” and the number of modules con-

nected in series, is given by relation 6 in Chap. “ Functional Design of the mCCHP-

RES System ” . It results in SMs = 2. Using the relation 7 in Chap. “ Functional Design of

”

the mCCHP-RES System results the number of rows of modules, n SMp = 5 con-

nected in parallel. In this way the topology of the PV panels is established.

B. Batteries capacity
For dimensioning the batteries is necessary to determine the energy stored in the
batteries (E need ), based on the condition imposed, namely that in the month with the
highest consumption of electricity (February) when neither working the CHP unit
and nor the PV panel. Choosing 1 day (24 h) as the N day need and using data from
Tables 12 and Eq. 8 in Chap. “ Functional Design of the mCCHP-RES System ” ,it

result E need = 30 kWh.
Battery voltage is imposed to voltage DC network V bateries = V cc and choosing
the battery voltage V battery = 12 V with C battery = 250 Ah [ 9 ], results the number of
the batteries connected in series n 1 =4.
To determine the capacity of the batteries

' system is used the Eqs. 10 and 11 in

Chap. where ND = 0.7 and RT =

1 was used. Thus, we obtain C batteries = 625 Ah and C 20 = 892 Ah.
Were used the Eq. 12 in Chap.

“ Functional Design of the mCCHP-RES System ”

“ Functional Design of the mCCHP-RES System ”

to determine the numbers of battery rows n 2 and Eq. 13 in Chap. “ Functional

Design of the mCCHP-RES System ” to determine the number of batteries, resulting

C 20

n 2 = 4 and n batteries ¼ n 1 n 2 ¼ 16 where

C battery ¼

3 : 57. In this way results the total

capacity of the batteries ' rows of 1,000 Ah.

C. Solar charge controller

The PV panel is connected to batteries with the solar charge controller. The solar
charge controller regulates battery voltage and output current based on the power
available from the PV panel and the state of charge of the battery. The solar charge
controller automatically charges the batteries in an optimal way with all the
available solar power using its algorithm for Maximum Power Point Tracking
(MPPT). The MPPT continuously seeks out the solar generator s optimal voltage to

retrieve the maximum available energy. This operating point varies depending on

'