My Solar Power Journey: Insights and ROI Calculation

I recently had a detailed conversation with the team from one of the solar vendor regarding solar power installation for my home, and I wanted to share the insights I gained.

Key Questions I Asked and Their Responses:

1. ROI (Return on Investment)

This was my top concern since Bangalore has around three months with minimal sunlight. I asked how feasible it would be to recover my investment in a reasonable period.

Their response:

They assured me that even with reduced sunlight during certain months, a 1 kW system would generate a minimum of 4 units per day on average.

My calculation:

On average, my electricity bill comes to around ₹2,500 to ₹3,000 per month.

Units consumed:

₹2,750 (average bill) / ₹7.50 (rate per unit) = ~367 units per month

Solar generation and excess units:

Assuming 1 kW generates an average of 6 units per day (since we occasionally go on holidays), a 3 kW system would generate:

3 kW * 6 units/day * 30 days = 540 units per month

Excess solar power earnings:

Of these, 180 units would be excess and can be fed back to the grid. BESCOM offers around ₹3/unit, so:

180 units * ₹3 = ₹540 per month earned from excess power

Total savings and buyback earnings:

₹2,700 (savings on usage) + ₹540 (excess power earnings) = ₹3,240 in total savings per month (or ₹38,880 annually)

ROI:

If the system costs around ₹2.5 lakhs, and I save roughly ₹38k per year, the return on investment would be around 5 to 6 years.

Caution:

These are rough estimates, and actual results could vary. I encourage everyone to do their own calculations based on their electricity rates and solar potential before making a final decision.

2. Space Utilization

Space was my next concern, particularly since I wanted to maximize solar generation on my 30x40 plot.

Their response:

For a plot this size, I could comfortably install a 4 kW system on my rooftop. However, since I’m planning for a 3 kW system, it would require about 180 to 200 sq. ft. They also offered to come and inspect the space for a more accurate assessment.

3. Meter Installation and Payment Timing

We haven’t yet received the BESCOM RR (service number), so I’m not keen on proceeding with the full installation until this is finalized. To avoid any delays, I proposed paying a token amount (10%) to confirm my interest, with the full payment to be made once the RR is generated.

Waiting for their response on this.

4. Additional Components

I’ve requested that the quotation includes a grill for each kW and a whole-house stabilizer as separate items. This way, I can ensure my entire house is protected from voltage fluctuations along with the solar setup.

5. Panel Maintenance

One key consideration is keeping the solar panels clean, as dust can significantly reduce efficiency. The vendor suggested that the panels be cleaned every two weeks, which can easily be done using a water spray.

6. BESCOM Approval

The good news is that a 5 kW system has been pre-approved by BESCOM for my property, so I have flexibility with the system size. This makes the process simpler, as I can choose to go with any vendor once I’m ready.

7. Government Subsidies

We are eligible for government subsidies, which will further reduce the cost of installation and shorten the payback period.

8. End-to-End Service

The vendor assured me they would handle everything from installation to the final BESCOM paperwork and bill generation. This includes all the formalities and file submissions, making the process much smoother for me.

Conclusion:

These insights are based on my personal experience and discussions with the vendor.