Frequently asked questions
PV, short for Photovoltaic, derives its name from the process of converting light (‘photo’) directly into electricity (‘voltaic’). Simply put, a Solar PV system is a power station that generates electricity from sunlight.
The main components of a Solar PV system are:
1. Solar Panels/Modules: Solar panels consist of a group of small cells made from semiconductor material. When the sun’s light falls on the modules, it excites the electrons, thereby creating direct current (DC).
2. Storage Battery: The best use of solar energy is to consume it while it is being generated. If the requirement is to store this power and consume it in the non-sunny hours, then solar energy can be stored in batteries for later consumption.
3. Solar Inverter: The DC electricity goes into an inverter that converts it into alternating current (AC). We use AC for running our household or office or factory equipment.
If you planning to install a solar plant, below are some things to consider:
What are your energy demands? How do you consume the power ?
What is the availability of the shadow-free area on your rooftop or building premises ?
What is the buying option you find more commercially viable (CAPEX or RESCO) ?
What would be the savings if you go solar ?
Most panel manufacturers give warranty of 25 years, however, there have been plants in operations for 40 years as well.
There are various factors involved in choosing your PV system. You might want to research on them before choosing the apt model:
- Energy Consumption Pattern
- Power Cuts or outages
- Various Govt. Policies like Net Metering, Grid Power Access or subsidies on Solar power.
Site survey is necessary to design a correct and profitable solar energy generation system for the owner of the system.
The location of solar panels, their direction, orientation and the potential of sunlight play an important role in determining the amount of energy you can generate from the sun.
Finance
There are two main buying options available in the market:-
OPEX Model – In this, a third-party investor owns the solar plant. The consumer and the producer enter into a PPA (power purchase agreement) for a decided duration of time which is typically 15-25 years. During the tenure of PPA, the consumer pays the producer for the power generated at a decided tariff. After the PPA terminates, the solar plant is transferred to the consumer.
CAPEX model – In this, end consumer owns the solar plant by purchasing it upfront and can avail various financing options like bank loans to finance the solar plant.
Net Metering is a policy which allows you to sell excess solar power generated back to the grid ensuring maximum savings from the solar plant.
Below are the approximate costs for a 100KW set up:
- Rs. 65-75 lacs for the household sector
- Rs. 55-65 lacs for larger commercial & industrial sector
- Utility-scale is even cheaper owing to economies of scale
Solar power is much cheaper than the power from grid and diesel generators. Today average cost of power from solar is Rs. 4.5-5 per kWh (For commercial and Industrial segments) while the average cost of power from the grid is Rs. 7 per kWh and Rs 16 per kWh from a diesel generator. (A litre of diesel generates around 3-4 kWh).
In OPEX model with no initial capital investment from the client, systems start paying for itself immediately as solar Tariff is way lesser than your current cost of power from Distribution Company and Diesel Generator Backup set. And as the gap between solar tariff and the grid tariff increase over the years; the savings also increase.
Installation & Maintenance
It can range between 2-10 weeks depending on the complexity of the project.
If your roof is not having any shade from adjacent buildings, trees etc and its structure is not delicate then your roof is suitable for installation of solar plant.
The annual maintenance cost is not very significant as the system only requires cleaning of modules (every 2-3 weeks) and basic preventive and corrective electrical maintenance (every 3 months) Water is generally used to clean the panels.
This would depend on various factors such as the shadow-free area available, the orientation of the roof etc, however, as a thumb rule, we can assume 1KW plant requires 12 sq meters of shade-free area.
Generation
It is advisable to install an energy monitoring system along with your solar plant that will allow you to compare the actual with the estimated performance on daily, monthly and annual basis.
Following factors should be kept in mind:
Location and layout of the solar plant.
Roof Orientation and shade-free area.
Quality of equipment
Design of the solar plant.
Maintenance of the plant.
On an average, every 1 KW setup produces 1300 to 1500 units in a year. This may, however, vary based upon the location of the plant, seasonal factors, surroundings and shadow-free area available. You can consider 1400 units for sake of calculations.
The electricity generation of the plant suffers during rainy and cloudy days especially during the monsoon season, but the generation never drops to zero. The loss of generation during monsoon and other rains is already adjusted in the 1.3 to 1.5 Lakhs unit/100kWp/annum generation number.
No, Solar energy is integrated into the LT panel of consumer premises, wherein DG, Grid or other generator sources would be feeding power as of now. When solar energy is injected, the equipment is unaware of the source from which power is feeding in. Hence it is not possible to segregate the loads on basis of the power source.
Technically yes, a solar plant can meet your entire power requirement if it is backed by battery energy storage system (BESS). But practically, for commercial and industrial users where the power requirement is higher, it would be recommended to use solar in sync with the grid. When in sync, priority is automatically given to the solar power to be consumed first.
The Solar plant will generate electricity only during the Sunny hours, typically between 6.30 A.M. to 5.30 P.M and will not generate any electricity during the night.
