Case study · Solar
Wholesale Merchant Grid Bidding & Automated PPA Settlement
A clean energy asset manager operating 380 MW of utility-scale solar and paired Battery Energy Storage Systems (BESS) in ERCOT and CAISO wholesale markets.
Engagement record
- Client
- Merchant solar portfolio owner
- Industry
- Solar
- System
- Wholesale Grid Bidding & PPA Settlement AI
- Timeline
- 6 Weeks
About this write-up
This case study describes the engagement as recorded. The client is not named; figures and outcomes are as reported by the client and have not been independently audited.
The challenge
The portfolio owner spent 18 days each month manually reconciling 15-minute revenue meter data against complex Power Purchase Agreements (PPAs) with contract-for-difference (CFD) formulas and nodal basis differentials. Additionally, manual curtailment delays during negative wholesale pricing hours incurred steep grid penalty charges.
Objectives
- Connect 15-minute utility revenue meters, ISO pricing APIs (ERCOT/CAISO), and PPA contract terms.
- Automate real-time inverter curtailment and battery charging during negative nodal pricing hours.
- Compress monthly PPA settlement billing to 24 hours and eliminate billing dispute write-offs.
Discovery
Billing reconciliation audit showed that commercial analysts manually cross-referenced over 2,800 15-minute meter intervals per month in Excel, resulting in calculation discrepancies that delayed cash settlement by weeks.
What was built
- Utility Revenue Meter & ISO Settlement API Connectors. Ingests certified 15-minute revenue meter data and ISO nodal pricing statements automatically.
- Real-Time Wholesale LMP Curtailment & Storage Co-Optimizer. Triggers battery charging and inverter curtailment whenever nodal pricing turns negative.
- Contract-for-Difference (CFD) Tariff Settlement Engine. Reconciles generation against contract strike prices, basis hedges, and index collars in seconds.
- Environmental REC Registry & Accounting Ledger Bridge. Syncs verified MWh generation directly to WREGIS/PJM-EIS registries and ERP accounting ledgers.
Outcomes as reported
Reported summary: 18d → 24h PPA Settlement & $380K Dispute Recovery.
| Figure | What it refers to |
|---|---|
| 18d → 24h Settlement | Monthly PPA billing reconciliation and invoice generation compressed by 94% |
| $380,000 Saved | In avoided billing dispute write-offs and delayed settlement true-up adjustments |
| 100% Penalty Avoidance | Zero negative wholesale electricity pricing penalties incurred through automated curtailment |
| 0 Audit Exceptions | Full compliance with FERC and institutional project finance audit standards |
Figures as reported in the engagement record; not independently audited.
Lessons
- Automating 15-minute interval reconciliation against ISO nodal pricing eliminates human spreadsheet error completely.
- Paired battery storage co-optimization turns negative pricing hours into profitable charging opportunities.
Next steps
Integrating automated capacity market bidding and spinning reserve ancillary service dispatch.
Implementation questions
It calculates the hourly difference between agreed strike prices and ISO hub settlement prices, generating verified bilateral invoices.
We support CAISO, ERCOT, PJM, MISO, NYISO, SPP, and European wholesale markets.
Contract modeling, meter connector configuration, and billing reconciliation were completed in 5 weeks.
