Solar ROI Calculator
Enter your electricity bill amount. Get instant analysis with payback period, returns, and honest recommendations.
Currently supports TNEB (Tamil Nadu) only
Common Questions
Tamil Nadu and most other states' electric bills come in a slab-by-slab basis, which means the more you consume, the more you pay a different amount for each unit. So the process is not straightforward. It depends on how much you start offsetting from the top slab. For example, if you are consuming at the ₹11 tier, you will be offsetting that first. Because of this variable nature, it is hard to give a fixed 'price per unit' offset.
The core part of this calculator relies on accurate slab pricing data. Integrating other states involves a manual process to ensure accuracy with their specific tariff orders. We are working on adding more states soon.
This calculator covers only residential connections. For businesses, the starting tariff rate is often ₹10 or more, so going solar is generally a financial 'no-brainer' with very high ROI. The question of 'should I?' is rarely an issue for commercial rates.
Solar energy drastically reduces your carbon footprint. Roughly 75% of our grid power comes from traditional method (thermal/coal). By switching to solar, you directly offset carbon emissions. In our calculator, we even show the equivalent number of trees planted to visualize this impact.
The installer or we can help you with this process. We will assess upfront if you are eligible based on the latest guidelines. Since government schemes can have capped budgets or timelines, it is recommended to apply sooner rather than later.
Yes, many banks are offering green energy loans with interest rates as low as 6-7%, which is comparable to or even less than inflation. We strongly recommend taking a loan to keep your initial capital low. We can assist you in connecting with the right banks for these specific solar plans.
According to TNEB, there is a nominal net metering charge (approx. ₹100 per kW). The costs for meter replacement and application fees are typically included in the 'Initial Investment' amount shown in our calculator.
For a standard 'On-Grid' system, the solar generation stops during a power cut for safety reasons (anti-islanding). It does not act as a backup generator. The primary purpose of on-grid solar is to reduce your electricity bill and offset costs, not to provide backup power during outages.
The grid acts as a massive battery for you—storing excess power during the day and providing power at night. To maintain this infrastructure, TNEB charges a nominal fee. Compared to the massive savings you get by offsetting your high-tier bill units, this fee is negligible.
Yes, but technically you aren't running them 'directly' on solar alone. Your home remains connected to the grid. If your solar production is high, it feeds the load; if it's low, the grid makes up the difference. This seamless switching means you can run any appliance without worry.
We generally recommend Monocrystalline (Mono PERC) panels for Tamil Nadu. They are more efficient in converting sunlight to electricity, require less roof space, and perform better in lower light conditions compared to older Polycrystalline technology.
A general rule of thumb is about 100 sq. ft. per 1kW of capacity. If roof space is limited, you can raise a pillar structure to mount the panels, allowing you to utilize the space underneath for other purposes like a roof garden or storage.
No, if installed correctly. Professional installers use chemical waterproofing and proper mounting blocks (civil foundations) to ensure no water seepage occurs. Alternatively, raising the structure on pillars avoids drilling into the roof slab entirely.
Generally, no. The solar system connects to your main distribution board. You won't need to rewire your entire house. The only change is usually swapping your existing meter for a bidirectional 'Net Meter' by TNEB.
Product Warranty (usually 10-12 years) covers manufacturing defects. Performance Warranty (usually 25 years) guarantees that the panels will still produce a certain percentage (e.g., 80%) of their original power output even after 25 years.
Solar systems are essentially assets. They can be dismantled and reinstalled at a new location. While there is a labor cost involved in shifting, the panels and inverter themselves are fully reusable at your new home.