We all understand the benefits of
solar energy. Currently, it is the hot topic among residential sector. And why
not? With reducing price of Solar system and constant support from government
on form of subsidies, it is great time to invest on SOLAR and enjoy butter for
next 25 years.
Tea is best prepared when one
knows about the quantity of ingredients to be added. So, the question is HOW
MUCH? How much capacity of solar system can you install in your premise. In the
current blog, we will be talking about grid connected Solar PV system. The
capacity of system is dependent on the load of the consumer. In simpler words,
it is dependent on how much appliances one use during the day.
In the below example, we have considered
a typical 2 BHK house with basic electrical appliances.
Let’s assume that the below chart represents consumption of
a house in a day;
Equipment
|
Quantity
|
Power Consumption (W)
|
No. of Hours
|
Total consumption (Wh)
|
Fan
|
3
|
50
|
6
|
900
|
Tube light
|
3
|
35
|
6
|
630
|
CFL
|
3
|
12
|
8
|
288
|
AC
|
1
|
1200
|
4
|
4800
|
Washing Machine
|
1
|
750
|
0.5
|
375
|
Refrigerator
|
1
|
150
|
10
|
1500
|
Miscellaneous
|
1
|
200
|
1
|
200
|
Total Consumption
|
8693
|
|||
Margin@10%
|
869.3
|
|||
Total Consumption in
kWh
|
9.56
|
|||
A typical solar system with
capacity of 1 kWp generates 3.5-4 kWh. The solar calculator by NREL; PVWatt gives consumer an idea about the annual generation by solar PV system. Considering the same, a solar system of 2-2.5
kWp would be sufficient for the above table. One need to consider peak
consumption during the day.
A better and accurate method to
calculate the load would be an electricity bill. Analyse the electricity bill to
find monthly consumption & daily peak consumption and accordingly install
the PV system.
Apart from the consumption of the house there are some other
factors which has to be considered while determining capacity of the system,
such as:
Sanctioned Load
This can be
determine by going through the electricity bill. Government allows only a
percentage of total sanctioned load to be capacity of system. Kindly refer the
solar state policy to know the allowed percentage.
Shadow Free Area
One of the key
factor when it comes to installing solar system is shadow free area. Shading on
single module affects the performance of whole string by increasing shading loss. Hence it is important to
identify area without obstacle before installation. To install 1 kWp of system, approx. 100-125 sq.ft. is needed.
Orientation of House
This is one factor
which is not in your control. There are scenario where the house/ flat are not facing
true south. In such cases, it is advised to change the orientation of the system
to true south to achieve maximum output. This would definitely reduce the capacity
of the system which you could have installed in orientation of house.
