Buyers publish an open model contract for utility-scale battery procurement
Victoria Shinder2 min readA group of battery storage buyers launched the Energy Storage Contract Alliance (ESCA) on 13 October 2026 and published a model supply and purchase agreement for utility-scale battery energy storage systems. According to Energy-Storage.news, the alliance has 22 member companies, among them independent power producer Neoen and developers BW ESS and MN8 Energy; ESCA says its members — utilities, IPPs, developers, insurers and asset owners — hold a combined BESS portfolio of more than 40 GWh.
The problem it names. ESCA's starting point, as stated on its website, is that a BESS contract is by default written by the supplier. The alliance argues that supplier templates are built around the supplier's own guarantees and often leave topics vague or out, naming serial defects, cell traceability and inspections. Arthur Claire, ESCA's secretary general and director of technology at quality-assurance provider Sinovoltaics, told Energy-Storage.news that most contractual answers are not project-specific and used to stay "in each company's drawer".
What the model contract contains. The clauses are publicly readable; 15+ technical appendices on cells, racks, system specifications, warranties, monitoring, calibration and spare parts are for members. The public text gives a sense of the buyer-side positions:
- the seller must provide traceable data on the origin of all cells and components within 14 days of the start of each manufacturing batch;
- firmware must be verifiable via SHA-256 or equivalent, critical vulnerabilities notified within 72 hours and cybersecurity incidents within 24 hours, with NIS2 and IEC 62443 compliance mandatory;
- every container is inspected, no sampling, with acceptance quality limits of zero for critical, major and minor defects, and nothing ships without a pass certificate from the buyer's third-party inspector;
- late delivery triggers liquidated damages of 0.2% per day from day 16 after the delivery period;
- payment is 10% on factory acceptance, 90% within 30 days of final delivery, and ownership passes on successful site acceptance testing.
What it does not do. The contract sets no prices, price levels or discounts; those stay with each buyer and supplier. ESCA also offers a steering committee with voting rights on how the text evolves.
Whether suppliers accept such terms is a negotiation question the document cannot settle; what it changes is that a buyer without its own battery and contracts team no longer has to start from the seller's draft.
Sources: ESCA, model BESS supply and purchase agreement — https://escabattery.org/ · Energy-Storage.news, launch report — https://www.energy-storage.news/neoen-bw-ess-and-mn8-back-efforts-to-standardise-bess-procurement-through-new-energy-storage-contract-alliance/