Personal Guide to Install Solar at Home: Part 1 – System Type

Buying and installing a rooftop solar system needs a lot of planning and preparation. And, if you hire a solar contractor or licensed installer to do the job for you, your informed participation would guarantee that quality panels are installed at a fair price, with the correct device size being selected and positioned in an ideal orientation.

To help you with understanding your rooftop solar installation process in detail, we are launching a blog post series. The series guides you through the site assessment, the energy audit, the design process, the sizing of the device, the deployment, and other phases involved. This blog post is the first of our five-part series – ‘Personal Guide to Install Solar at Home.’

Step 1: Evaluate your Options

Here are some of the factors you will have to consider before you install a rooftop solar system:

1)   Location

The geography of your location and the weather will decide how much sunlight you can get all year round. It would affect the number of solar panels you need. For instance, if you live in a location where trees, tall buildings, or other major barriers are present, the photovoltaic system may not receive enough daylight. The solar panels with battery for home need adequate sunlight every day to provide enough kilowatt-hours and easily meet your residential electricity requirements.

2)   Rooftop Condition

If you have a deteriorated roof, the structural foundation of the solar system will be bad. You will not be able to mount photovoltaic panels until you first fix those issues. Repairing the roof is always an easy solution, which shouldn’t cost you a lot.

3)   Type of Solar Panel

Choose which type of panel you would be interested in mounting:

• Monocrystalline
• Polycrystalline
• Thin-film
• Bifacial
• PERC

Each type has its unique strengths and drawbacks. Based on the factors particular to your site and preferred system features, the solar panel model ideally fit for your installation would vary. The most common solar panels used today in solar roof installations are monocrystalline solar modules. Among homeowners looking to install solar panels on a budget, polycrystalline panels are economical.

Thin-film panels are futuristic and may be applied by an adhesive directly to a surface (roof, boat, or RV). With traditional solar panel systems now competitively priced, a bifacial system offers higher performance and can take up less room. In awnings or pergolas, bifacial solar panels fit well. If the suitable roof space is small, a solar array capable of the power you need can be made a reality by using PERC solar panels.

4)   Tilt Angle

The tilt angle is a crucial factor to consider. It is the angle between the horizontal ground and the solar panel. The tilt angle of the solar module can be adjusted as per the latitude of your location. Typically, it is assumed that the panels positioned at a tilt angle equal to the latitude will produce the highest amount of output. You may also use a solar tracker to improve the efficiency of the system.

Listed below are the latitudes of the cities in India:

• Zone 1: J&K, Punjab, Himachal Pradesh, Uttarakhand: 30-36°
• Zone 2: Rajasthan, UP, Delhi, Haryana, Bihar, North Eastern States: 24-30°
• Zone 3: Gujarat, MP, Jharkhand, West Bengal, Maharashtra, Chhattisgarh, Orissa: 18-24°
• Zone 4: Karnataka, Tamil Nadu, AP, Telangana, Kerala: 12-18°

If all of this feels too complex for you, don’t fret! HomeScape helps you to assess the right configuration for your solar-powered rooftop and takes care of all the steps for you.

Step 2: Energy Audit and Load Calculation

To find out the load that your solar PV system should cover, perform a load analysis. For instance, your fridge, dryer, television, lamps, microwave, and computers may all be up and running at once, so you’ll need a solar system big enough. Take the battery bank into consideration in case you are planning to install an off-grid system, i.e. solar panel with battery for home. This step helps you to determine how many kilowatt-hours the system needs to produce to meet your energy usage per month.

An intense energy audit requires the following steps:

• Make a list of old appliances and try to replace them with newer, energy-saving ones.
• Check to see which appliances stay on, or in 24/7 standby in your home while not in operation, and start switching them off.
• Replace incandescent light bulbs with CFL bulbs, if you’ve not already.
• Blinds or thick curtains can be used to prevent harsh exterior temperatures from radiating into the building.

The following steps should help you with the calculation process:

1)   Solar System Capacity

How many units of electricity do you consume on an average monthly?

For instance, if you use 1400 kWh per month, let’s say an average of 6 hours of daylight every day, this means that at least every hour you will need 1400/(6 x 30) = 7.7 kW, that is approximately 8-10 kW. If you have an idea about the available space on the roof, you can also try using our Solar Calculator.

The following parameters specify the size of the plant:

• Monthly average Bill peak load in summers and year-round
• Estimated Load
• Area of the rooftop or shade-free space

2)   Area Requirement

1 kW requires 10sqm or 100sqft of shade free area. It can be adjusted and installed with existing structures on roofs such as tanks, storerooms and staircases.

3)   Payback Period

Did you know that a solar system reduces your electricity bills by up to 90 per cent? Depending on the electricity bills, the payback period is around four to five years. The total number of years in which the original sum of money spent on the device can be recovered from the profit is known as a solar system’s payback period.

For instance, if you have spent Rs 5 Lakhs in a solar system that provides you with annual savings of Rs 1 Lakh, this ensures that your initial investment has been paid back within five years.

In conclusion, the installation of a solar system (either on-grid or solar panels with battery for home) is not very difficult, nor is it incredibly costly. In this article, we covered the initial few steps: factors to consider before installing a solar system, load calculation, as well as performing an energy audit. We hope you found the first part of our blog series useful. Follow us to know more in our upcoming parts of the personal guide blog series.