FAQ

Solar panels consist of a series of solar cells placed together in arrays to generate electricity from the sun. A rooftop solar system is one in which solar panels are mounted on the roof of residential, commercial, institutional or industrial buildings to generate electricity. Energy demands of the host can be met by a rooftop solar system and any excess energy can either be stored in a battery or be transmitted to the grid.

Solar panels can be installed on both sloped as well as flat roofs. On the flat roofs, additional mounts and racks are needed in order to angle the panels for higher efficiency. In terms of the rooftop material, reinforced concrete, metal and asphalt shingle roofs are the most preferred for solar panel installations. The material should have a high strength to weight ratio, be durable and energy efficient. For a complete assessment, consult a specialized solar EPC contractor.

It is true that solar panels work most efficiently when exposed to direct sunlight. However, these panels utilize both visible light and infrared light to create electricity, both of which are present during cloudy or rainy days as well. Thus, even during full fledged monsoon season, the output of your solar panels will not be zero. The efficiency of a solar panel on a cloudy or rainy day is dependent on the material utilized in the panels as well as the angle at which panels are installed. On average, panels manage to maintain 50% efficiency even on a rainy day.

The solar industry has developed a mechanism through which they classify solar panel manufacturers into three different tiers based on a variety of different factors such as experience, manufacturing scale, durability and quality of the products, etc.

Tier 1 manufacturers are supposed to be the best followed by tier 2 and then tier3. Just because the manufacturer is tier 1 doesn’t imply that every solar panel produced by that firm will be of the highest quality, but there is a positive correlation between tier of company and solar panel quality.

In most studies we have read so far, the list of top 10 solar panel manufacturers tends to be dominated by Chinese players. Thought China produces a lot of junk products as well, the panels from tier 1 companies can be trusted.

Tier 1 companies use the best grade of silicon, are vertically integrated – they make their own cells and wafers, control the manufacturing process with advanced robotics and invest heavily in R&D. Thus, they tend to provide the best products at reasonable rates.

Panels from Tier1 companies, though a little more expensive, are worthwhile in the long run because:

1. They will be more durable and in the long term, prove to be more cost effective 2. They tend to come with a performance warranty from re-insurer

Again, the answer to this question depends on a lot of factors. In Delhi/NCR, the amount of sunlight received is substancial, so that factor is out of the way. The other main criteria for any consumer is how much do you tend to spend on your electricty bill? If you pay around 2500 per month on average, then installing a solar PV project will be economically viable for you. Here is why:

1. The manufacturers of solar panels give a warranty of 25 years, so the panels will continue to provide output for at least that many years 2. You will be able to get your investment back in around 3.5 to 5.5 years in terms of savings on your electricity bill. This will happen even if you have taken a loan to pay for your installations (15 year loan at 9.5%) 3. After 5.5 years, all the savings on your electricty bill will in a way be free electricty!