Rooftop solar panels are installed on roofs of residential, commercial, or industrial buildings to capture solar energy from the Sun and convert it into useful electrical energy. Thus, a clean, harmless form of energy is created which can be harnessed by the house owners for different household purposes requiring electricity.
When photons strike the solar panels on the roof, electrons are emitted which become a source of Direct Current(DC). An inverter converts the direct current to alternating current(AC) which is required in households. This is a guide on everything you need to know about rooftop solar panels. Click here to read more.
1. How do rooftop solar systems work?
The solar panels on roofs are based on inbuilt solar cells which are small, square-shaped semiconductors made of materials like Silicon. Most solar cells are photovoltaic cells. A photovoltaic(PV) cell is the main functional component of a rooftop solar panel. PV cells are of 3 types-
- Single-crystal cells: Operates at higher power, and increases household efficiency by 30%.
- Polycrystalline cells: Small square cells, thus allowing close packing of cells to increase energy production.
- Amorphous silicon: Least expensive and has the lowest efficiency among all PV cells.
2. Main components of the rooftop solar system
The key components that constitute rooftop solar panels are-
- Solar panel: Most important component, converts solar energy to electrical energy.
- Solar inverter: Converts Direct Current to Alternating Current.
- Solar Battery: Stores solar energy and uses it later when the grid turns off.
- Module Mounting Stand: It protects the solar panels from blowing away due to wind at a specific angle.
Some other important components required for the installation of solar panels on the roof are-
- DC wire and AC wire
- DCDB: Protects the panel from the DC side
- ACDB: Handles the AC.
- MC4 Connectors: Connects solar panels with each other.
- Lightning Arresters(LA): This secures the solar panels and associated appliances from sudden power bursts due to lightning strikes.
- Earthing Kit: There are two earthing kits-one for the inverter and one for the LA(Local Earth).
3. Types of Rooftop Solar Systems
There are three classes of solar systems as follows-
- Grid-tied: This primarily feeds the power generated back into the grid while power is drawn for different household applications.
- Grid-interactive: Acts as a diesel generator or a backup for battery
- Off-grid: Works in off-grid areas, with a battery backup and diesel generator.
4. How to choose the suitable rooftop solar system
When you are installing solar panels on the roof, you should be aware of the conditions that would make your solar panel the most efficient. Some of the characteristics are-
- Certifications: The solar panel that you choose should be certified by BIS( Bureau of Indian Standards). Solar panels are a long investment, thus you must choose a reputed brand.
- Inverter Efficiency: The more the efficiency of the inverter, the greater the power. Efficient inverters also save a lot of money. The more efficient the inverter, the greater the AC generated which is used for household applications.
- Types of panels: There are two types of panels- monocrystalline panels and polycrystalline panels. To choose the right one, check the size of your roof and assess your budget.
- Cost: Cheaper solar panels may save you money but the quality of the components, warranty periods and installation are not reassuring. They will not last long and in investments like solar panels, you need durability. Thus you should always keep in mind the quality and warranty of the product while buying it. Even if it may cost you more now, it will be profitable in the long term.
The starting range of a 1 KW rooftop solar panel amounts to Rs. 55,000- Rs. 85,000. 1 kW of power is sufficient for an average family. However, if you have an air conditioner and other such appliances, or a large family, you will need a power of around 3-5 kW. However, solar panels are beneficial in terms of money. They are a source of long-term sustainable energy for our daily needs, control pollution, and lower our expenses.