On-grid SPV system
Earth 47 will install solar panels on your roof which convert sunlight into electricity that can be used to power your home. The electricity passes through a solar inverter to be made ready for your use by converting it from DC to AC.
If the panels produce more electricity than is needed by you at any moment, then this excess energy is 'exported' to the grid through a special meter called 'net meter', which will replace your existing meter. The meter keeps a record of how many units you export. Think of it like depositing the electricity in a bank.
Suppose some day your requirements are more than the electricity generated. In this case, the 'net meter' pulls electricity from the grid to meet your requirements and records it as 'import'. This is deducted from the balance of your exported units.
At the end of the month, you get a bill for the net units used by you=export-import.
We design the system in a manner such that export equals import. This ensures that your electricity bill is reduced massively.
This system does not have a battery back-up, but uses the grid for storing excess energy. This means that the system does not work in the case of a power cut. In case you are looking for a system with back-up please refer to our off-grid or hybrid system pages.
On-grid systems are primarily available in three options - String inverters, Micro-inverters and Optimizers
In a string inverter based system, all panels are connected in a series and their cumulative DC output is converted into AC current by a single inverter. These systems are easiest to design and install and also the most cost effective given that they have fewer electronic components.
However, being connected in series, all the panels produce output equal to the lowest performing panel. One dusty or shaded panel can reduce the output of the whole system.
This means that string inverters are best suited in situations where all panels can be installed in a shadow free area in an optimal direction.
In a micro-inverter based system, each panel’s DC output is individually converted to AC by a small inverter attached to the panel. This ensures that output is optimized for each panel and drop in one panel’s performance does not affect the output of the system as a whole. These systems allow you to get the maximum solar generation from your rooftop and have the following added advantages:
- Panel level monitoring compared to only system level monitoring in string inverters
- No high DC voltage on the roof, leading to higher safety
- Minimize effect of shading, dust etc
- Easier maintenance and fault diagnosis
- Typically longer lasting than string inverters
In an optimizer based system, you get the best of both micro and string inverters.
An optimizer is connected to every panel of your solar system, providing you panel level monitoring and output maximization just as in case of micro-inverters.
Simultaneously, having a single inverter for the whole system allows you to lower overall system cost, resulting in significant savings for large scale commercial systems.
Off-grid SPV system
In areas where the grid reliability is poor, one can choose to install a completely independent off-grid system.
In these systems, the current from the panels is used to charge batteries which are then used to power your home after passing the current through an inverter.
Hybrid SPV system
Hybrid systems combine the best of both on-grid and off-grid systems.
When the power supply is available, this system works like an on-grid system allowing you export surplus electricity to the grid and reducing your electricity bill.
When the grid is down, this system works like an off-grid system, providing you back-up power through batteries.