Executive Summary
A massive Renewable Energy commitment should optimize your balance sheet, not leak capital. When a Tamil Nadu-based, listed pharmaceutical company signed a 100 MW Solar Open Access PPA, the headline numbers looked great. They successfully met the strict ESG targets required for their European and US export markets, and the baseline savings were highly attractive.
However, beneath the surface of the term sheet, a critical inefficiency emerged: out of 15 crore units generated, only 13 crore were being settled against their consumption. Two crore units of pure solar generation were going to waste.
By applying a precise, 7-step battery sizing methodology, the CFO was able to capture this wasted generation, pitch a mathematically sound Battery Energy Storage System (BESS) to the board, and unlock an additional ₹14-16 crore in Return on Investment (ROI). Here is the breakdown of how boardroom-grade energy teams turn wasted generation into high-yield assets.
The Financial Leakage: The 2 Crore Unit Gap
When executing a large-scale Solar PPA, generation curves rarely align perfectly with factory consumption profiles. In this scenario, the pharma plant was projected to generate 15 crore units annually. But because of the timing of the generation versus the timing of the consumption, 2 crore units could not be settled.
When the CFO took this standard solar proposal to the board, the directors immediately spotted the financial leakage and asked two critical questions:
- Why can’t we settle these 2 crore units?
- What are our options? Can we explore storing this excess power in a battery and utilizing it during peak evening hours?
The board’s proposal was conceptually sound and highly attractive to the CFO. But execution is where capital is either multiplied or destroyed.
The BESS Dilemma: The Cost of Guesswork
Transitioning from a standard solar PPA to a Solar + Storage model requires extreme mathematical precision. The CFO faced a significant hurdle: he was not sure how to accurately size the BESS solution.
In energy storage, sizing is everything.
- Oversizing the battery results in stranded CAPEX and a ruined payback period.
- Undersizing the battery means you are still wasting units and leaving money on the table.
Any miscalculation is a pure financial loss. The CFO needed absolute clarity on the precise battery capacity, the inverter sizing, the total economics, and the exact ROI payback timeline before bringing the mandate back to the board.
The Solution: The 7-Step Battery Sizing Methodology
To eliminate the guesswork, we deployed our proprietary seven-step battery sizing methodology. This framework is designed specifically for corporate energy consumers to calculate exact storage requirements based on their unique consumption profiles.
Instead of relying on a developer’s rough estimate, the framework walked the CFO step-by-step through:
- Calculating the exact generation vs. consumption mismatch.
- Determining the precise battery sizing required to capture the excess.
- Sizing the inverter to handle the discharge rate.
- Modeling the total economics and final payback period.
The Verdict: A ₹14-16 Crore Boardroom Victory
Armed with this exact mathematical framework, the CFO went back to the board. He did not pitch a generic “storage solution”—he pitched a highly specific, commercially optimized asset.
The final approved mandate included:
- A 110 MWh battery capacity
- A 35 MW inverter
By perfectly sizing the BESS to capture the 2 crore wasted units and deploy them during expensive evening hours, the board approved the mandate, locking in an additional ₹14-16 crore of ROI.
Next Steps for the Boardroom
If your manufacturing plant is facing un-settled generation, or if you are evaluating a Solar PPA but leaving evening consumption exposed to grid tariffs, you are leaking capital. Do not guess your storage requirements.
If you want us to run a Techno-Commercial Wealth Audit and apply this exact 7-step methodology to size a BESS solution for your consumption profile, connect with us to reserve your strategy session today.
About Infinia Solar
Infinia Solar is India’s leading renewable energy consultant.
We help Commercial and Industrial consumers procure the right renewable energy solutions, from the right developers, and on the right PPA terms.
We’ve served 60+ customers across 18 states, enabling 1.4 GW of open access and rooftop solar capacity, and have facilitated 150+ PPAs so far.
This has helped our customers reduce up to 50% of their electricity costs and replace up to 100% of their power with renewable energy.
We have also collaborated with 50+ developers, and our customers fondly refer to us as the ‘Amazon of the renewable energy industry.‘