System Sizing Worksheet for RE Display System 3 at ROTA |
|
Inverter Sizing |
Parameter |
Label |
Notes |
| Battery Charge Controller (BCC) efficiency |
98% |
A1 |
From Initial design Specification |
| System Voltage |
12 Vdc |
A2 |
From Initial design Specification |
| |
|
|
|
| Maximum Power Required |
50 W |
A3 |
Selected based on Maximum Demand |
| Total Energy Used |
148 Wh |
A4 |
from Energy Calculation |
| Current Draw at Maximum Demand |
4.2 Amp |
A5 |
3.4.1(a) recommends a limit of no greater than 120 Amp |
| System Voltage Suitability |
Yes |
|
|
| |
|
|
|
| BCC Inefficiency with load |
151 Wh |
A6 |
=A4/A1 |
| Total A-h per day |
12.6 Ah |
A7 |
=A6/A2 |
| Over supply coefficient fo RE only systems |
1 |
A8 |
3.4.2.5 Systems without a generating set |
| Selected BCC Specifications |
Morningstar SunLight SL10 |
A9 |
|
| BCC Efficiency |
98% |
|
|
| |
|
|
|
| Battery sizing |
|
|
|
| Number of days of autonomy |
3 Days |
B1 |
From Initial design Specification |
| Max depth of discharge |
60% |
B2 |
From Initial design Specification |
| Battery Capacity |
63 Ah |
B3 |
=A7*A8*B1/B2 |
| Lowest 24 hr Temperature |
25°C |
B4 |
Typical ambient condition |
| Temperature Correction Factor |
1 |
B5 |
From battery specifications |
| Adjusted Battery Capacity |
63 Ah |
B6 |
=B3/B5 |
| Selected battery |
GNB Vented leadacid Cell" 12V OGi 50 LA" |
B7 |
Selected |
| Selected Battery Voltage |
12 V |
|
From battery specifications |
| Selected battery discharge rate |
C10 |
B8 |
From battery specifications |
| A-hr capacity of selected battery |
50 Ah |
B9 |
From battery specifications |
| Number of batteries in parrallel |
1 |
B10 |
=B6/B9 (Rounded up) |
| Number of batteries in series |
1 |
B11 |
=A3/12 |
| Check: Capacity of selected battery at 10h rate |
50 Ah |
B12 |
From battery specifications |
| Capacity of battery bank at 100hr rate |
50 Ah |
B13 |
=B12*B10 |
| Max. Daily depth of discharge |
25% |
B14 |
=A7/B13 |
| Suitability of batteries? |
YES |
B15 |
|
| Estimated cycle life @ Max. Daily depth of discharge |
approx. 3500 cycles |
|
From battery specifications |
| Total number of batteries |
1 |
|
=B10*B11 |
| |
|
|
|
| Photovoltaic Array sizing |
|
|
|
| Design tilt |
~ 35° |
C1 |
From Initial design Specification |
| Design Month |
Yearly Average |
C2 |
From Initial design Specification |
| Daytime Average Ambient Temperature for Period |
20° |
T1 |
Selected from site data applicable when using MPPT controllers AS4509.2 clause 3.4.3.6 |
| Average Daily cell operating temperature |
45° |
T2 |
T2=T1 + 25 AS4509.2 clause 3.4.3.6 |
| Total Energy demand per day |
12.6 Ah |
C3 |
=A7*A8 |
| Battery efficiency |
85% |
C4 |
From battery specifications |
| Array Output required per day |
14.8 Ah |
C5 |
=(C3/C4) |
| Peak sun hours at design tilt for design month |
5.6 hrs |
C6 |
From Initial design Specification (AUST Solar Rad data) |
| Selected module |
BP Solar, BP275 Modules |
|
|
| Maximum Power |
75W |
C7 |
|
| Selected module I at 14V at NOCT |
4.55 Amp |
C8 |
From panel specification sheet |
| Selected module Power at 14V at NOCT |
64 W |
|
=C18*14 |
| Selected module nominal operating voltage |
12 Vdc |
C9 |
From panel specification sheet |
| Derating Factor for manufacturing tolerences |
95% |
f m |
From module specification sheet (note BP Solar minimum power tolerance is with minus 5 W from nominal power ) AS4509.2 clause 3.4.3.5 |
| Derating Factor for soiling tolerances |
95% |
f s |
|
| Derated Current |
4.1 Amp |
C10 |
=f m * f s *C8 (note spec for module is no more than -5W from nominal rating) AS4509.2 clause 3.4.3.7(1) |
| Derated Power of Module |
57.4 W |
. |
AS4509.2 clause 3.4.3.7(2) |
| Number of modules in series |
1 |
C11 |
=A2/C9 |
| Output per module |
23.0 Ah |
C12 |
=C10*C6 |
| Number of strings of modules in parallel |
1 |
C13 |
=C5/C12 |
| Number of Panels |
2 |
C14 |
Decided for high reliability |
| Total derated Output |
115 W |
C15 |
=C14*C10*14 |
| Total Rated Peak Output |
150 W |
C16 |
=C7*C14 |
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| Note: Average Solar radiation data |
