By HUA-X
Published · Updated
Key takeaways
- Give suppliers the same site and duty assumptions so proposals are comparable.
- Request usable energy and operating limits in addition to nameplate capacity.
- Define who supplies every balance-of-system component and service.
- Tie technical evidence to the exact quoted model and document revision.
1. Project basis and operating objective
State what the system must do, where it will operate, how success is measured, and which operating mode has priority when objectives conflict.
- Site, destination, application, and project schedule
- Normal, backup, islanded, maintenance, and failure modes
- Interval load, renewable, tariff, outage, and grid data
- Target power, duration, reserve, availability, and dispatch priority
2. Electrical, controls, and site interface
Define the point of connection and require a responsibility matrix for the battery, PCS, EMS, transformer, switchgear, protection, metering, communications, civil work, fire system, and commissioning.
For example, PowerFac-261 is an AC-connected cabinet rated at 125 kW with 261 kWh nominal battery energy. PowerFac-5M is a DC-side container with 5,016 kWh nominal battery energy. These ratings describe different system boundaries. State the required grid connection and who supplies the PCS, transformer, switchgear, EMS, cabling, installation, and commissioning before comparing quotations. The battery-container energy rating does not specify AC output power or a turnkey supply scope.
- AC and DC voltage, power, fault, protection, and interconnection data
- EMS, SCADA, protocol, metering, remote access, and cybersecurity requirements
- Ambient, altitude, enclosure, acoustic, seismic, corrosion, and access conditions
- Foundation, cable route, transformer, switchgear, fire, and auxiliary-power scope
3. Performance and evidence package
Ask for nominal and usable energy, continuous and overload power, efficiency basis, auxiliary demand, thermal limits, derating, degradation assumptions, alarms, and current model-specific compliance evidence.
- Controlled technical datasheet and configuration identifier
- Measurement point for usable energy and round-trip efficiency: battery DC terminals, PCS AC output, or site connection
- Auxiliary loads included in performance guarantees, plus separately stated standby losses
- Test temperature, state-of-charge window, charge and discharge rates, and beginning- or end-of-life condition
- Operating window, temperature limits, derating, and unavailable states
- Applicable certificates and reports with exact model references
- Drawings, manuals, alarm matrix, maintenance plan, and spare-parts list
4. Commercial scope and acceptance
Commercial comparisons should use a common incoterm, destination, quantity, scope, schedule, payment basis, warranty document, service responsibility, and factory and site acceptance criteria.
- Included equipment, software, documentation, services, spares, and exclusions
- Packaging, transport, destination, unloading, installation, and storage
- Production, factory test, shipping, site test, commissioning, and handover milestones
- Written warranty, support path, response scope, and acceptance test procedure
References and further reading
These sources explain the technical background. Product performance, approvals, and installation requirements must be confirmed for the quoted system and project.
Performance and Health Test Procedure for Grid Energy Storage Systems (2017) — National Renewable Energy Laboratory
Supports specifying efficiency, standby losses, usable energy, charge and discharge rates, and performance over system life when defining acceptance tests. This is a testing reference, not a current installation code.
Installation Codes and Requirements for Energy Storage Systems — FAQs — UL Solutions
A US installation-code reference for defining the fire-test evidence requested from suppliers. Confirm the applicable jurisdiction, adopted edition, and proposed installation.
