At a glance
| Country | Australia |
|---|---|
| Location | Inland New South Wales (as stated in the source material) |
| Application | Solar-farm energy storage and grid support |
| System | 5 MWh liquid-cooled containerized battery energy storage system with PCS and 22 kV step-up transformer |
| Voltage | Battery DC bus to PCS; 22 kV medium-voltage connection |
| Frequency | 50 Hz |
| Standards basis | AS 60076 series with the older AS 2374 series still referenced for transformers, AS 2067 for installations above 1 kV, AS/NZS 3000 Wiring Rules for the low-voltage installation, AS/NZS 5139 for battery system safety, AS/NZS 4777.2 for inverters within its scope and the National Electricity Rules generating-system performance standards above it, AS/NZS 61439 for LV assemblies, AS/NZS 1170 for wind and structural loading, AS 3959 practice where the site is bushfire prone, UN 38.3 and the Australian Dangerous Goods Code for transport |
| Visual status | Representative project visualization |
The engineering problem
Three things shape a storage system for this market, and one of them is not electrical.
The first is the grid interface. A 5 MWh system connecting at 22 kV in the National Electricity Market sits above the threshold where AS/NZS 4777.2 does the work, so its behaviour is set by negotiated generating-system performance standards with the network service provider and AEMO — reactive capability, voltage and frequency ride-through, active power control, power quality and protection settings. The mainland frequency operating standard holds a narrow normal band, of the order of ±0.15 Hz, and the frequency control ancillary services markets pay for response inside it. Whether the system is grid-following or grid-forming, and what its response times are, therefore drive PCS selection at enquiry stage rather than at commissioning.
The second is the inland climate. Summer ambient in inland New South Wales can sit above the temperature at which air-cooled equipment starts giving rating back, and the diurnal swing is wide. Liquid cooling holds cells in a narrower band and rejects heat better than forced air, but the chiller’s own capacity falls as condenser inlet temperature rises, so the design ambient has to be the site’s, not a nominal figure. Dust fouls heat exchangers, UV degrades polymers and cable sheathing, and bushfire exposure drives vegetation clearance, asset protection zones and the fire-protection concept.
The third is regulatory, and it is stated plainly here because it decides who can sell. RCM marking under the Electrical Equipment Safety System requires a local Australian Responsible Supplier — normally the importer — registered in the national database. MARS cannot hold that registration from outside Australia. The same pattern applies to GEMS registration where a transformer falls under minimum energy performance requirements: the registrant must be an Australian entity. MARS supplies the equipment, the test evidence and the technical documentation to support it; the Australian importer or first supplier holds the registration and applies the mark.
System configuration
| Item | Description | Specification notes |
|---|---|---|
| Battery container | Containerized enclosure housing racks, thermal management, fire protection and controls | Ingress and corrosion protection specified for inland heat, dust and UV; structural design to AS/NZS 1170 wind loading; separation distances and asset protection zone set at layout stage |
| Battery racks and modules | Lithium modules in racks with rack-level disconnection and fusing | System safety arrangement to AS/NZS 5139; module, rack and system-level monitoring of voltage, current and temperature; rack isolation accessible without entering an energised aisle |
| Battery management | Three-level BMS — module, rack and system — with contactor control and protection | Cell balancing, state of charge and state of health estimation, and hard protection limits that act independently of the site controller |
| Liquid cooling | Chiller, pumps, manifolds and rack cold plates on a water-glycol loop | Chiller capacity declared at the site design ambient, not a nominal one; coolant concentration set for both the summer duty and the coldest inland nights; leak detection, pump redundancy, flow and temperature monitoring, and delta-T across racks controlled to limit cell-to-cell divergence |
| PCS | Bidirectional conversion between the battery DC bus and the AC system | Grid-following or grid-forming as the connection requires; reactive capability, ride-through, active power control and frequency response functions demonstrated against the negotiated performance standards |
| Step-up transformer | Transformer between PCS output and the 22 kV connection | AS 60076 / AS 2374 basis with any applicable minimum energy performance requirement; cast-resin dry-type where fire load governs, or oil-immersed with containment; impedance matched to the PCS and to the network fault level |
| MV switchgear and protection | 22 kV switching, connection-point protection and metering | Protection settings and any anti-islanding or transfer-trip requirement per the network service provider; metering arrangement per the connection agreement and market registration |
| Fire detection and protection | Gas, smoke and heat detection, alarm, deflagration venting and the agreed suppression or containment strategy | Detection aimed at off-gassing ahead of thermal runaway; emergency shutdown interlocked with BMS and PCS; access, water supply and clearance arrangements agreed with the fire authority |
| Control and communication | Site controller with interfaces to the solar plant, the network service provider and the market | Modbus TCP, IEC 61850 or DNP3; telemetry, dispatch and remote control to the extent the connection agreement and market registration require |
Installation sequence
Overview
The contact sheet sets out the four stages of an installation of this type: container and PCS delivery, crane placement on the prepared foundation, inspection of battery racks and the cooling system, and the completed fenced installation with its 22 kV step-up transformer. The order follows what becomes inaccessible. Foundation, cable ducts, earth grid and drainage are complete and surveyed before the containers land. Cabling between container, PCS and transformer is measured on the actual positions. Coolant filling, leak testing and the first controlled charge come after mechanical and electrical work is finished, and the site is closed only once the fire detection and emergency shutdown chain has been proved.
Delivery
A battery container arrives as dangerous goods. Cells are transported under UN 38.3 test certification and, by road in Australia, under the Australian Dangerous Goods Code, usually at a restricted state of charge with the system electrically isolated, so documentation, labelling and transport state of charge are checked on receipt as carefully as the hardware. Long inland routes are assessed for axle loading, gradients, culvert and bridge capacity, headroom and turning radii, and for the unsealed final approach that many solar sites have. On arrival containers and PCS units are inspected for transport damage, seal and louvre condition, water and dust ingress, shock-indicator status and shifted internal fixings; racks are checked for module movement and connector integrity, and the coolant circuit is inspected before anything is pressurised.
Placement
Placement is a single lift of a heavy, tall and evenly loaded unit. Lifting uses the designated corner castings or lugs with a spreader beam so slings do not bear on walls, doors or roof-mounted cooling plant. Crane capacity is assessed at working radius, derated for wind on an exposed inland site, with outrigger bearing pressure checked against ground that may be dry crust over soft material. The foundation is confirmed level before the container is set down, because liquid cooling makes level a functional requirement: an out-of-level container traps air in the coolant circuit and biases flow between racks. Separation distances to other containers, to the transformer, to boundaries and to vegetation are confirmed against the fire-protection and bushfire layout before anchoring is completed to the wind-loading detail.
Internal work
Internal work covers DC connections, the coolant circuit and the control and safety wiring. Rack DC joints are torqued to value and marked, because a high-resistance joint on a DC bus carrying continuous current is both a loss and a fire risk, and a DC arc does not self-extinguish at a current zero. Polarity, rack isolation and fuse ratings are verified before any rack is closed. The coolant circuit is filled with the specified water-glycol mixture, vented, pressure-tested and run to confirm flow through every rack — uneven flow appears as cell-to-cell temperature divergence, which shortens life and is difficult to correct later. Leak detection, coolant flow and temperature monitoring, and the gas, smoke and heat detection loops are functionally proved, including their action on the BMS and PCS.
Completed configuration
The completed configuration shows the containers, PCS and 22 kV step-up transformer inside a fenced compound beside the solar plant. Before energisation the installation is proved as a chain: transformer ratio and vector group on every tap, insulation resistance recorded, earth continuity confirmed from every enclosure back to the earth grid, and grid resistance measured. Connection-point protection is proved end-to-end by injection, and the anti-islanding or transfer-trip path is demonstrated. Commissioning then moves to the grid interface: controlled charge and discharge, reactive capability across the required range, ride-through and frequency response behaviour, and the telemetry and dispatch path to the network service provider and the market. Compliance evidence gathered here supports the performance-standard demonstration, while RCM and any GEMS registration remain with the Australian responsible supplier.
Specification options
For a comparable Australian enquiry, MARS can configure energy and power rating, C-rate and cycle-life expectation, cell chemistry and rack architecture, with the BMS hierarchy and protection limits defined. Thermal management can be liquid or forced air, with chiller capacity, coolant chemistry and concentration declared at the site’s design ambient. PCS can be grid-following or grid-forming, with the reactive capability, ride-through and frequency response functions required by the connection. The step-up transformer can be cast-resin dry-type or oil-immersed with containment, at the required voltage ratio, vector group and impedance. Enclosures can be specified for IP rating, corrosion category, coating class, UV resistance and wind loading, with the fire detection, venting and suppression concept agreed against the site. Control and telemetry can be provided over Modbus TCP, IEC 61850 or DNP3. RCM and GEMS registration are held by the Australian importer or responsible supplier; MARS supplies the supporting test evidence and technical documentation.
What we need to quote a comparable system
Send as many of the following as you have. Missing items are not a problem — we will ask.
- Single-line diagram of the solar plant, the storage system and the 22 kV connection point
- Required energy and power rating, C-rate, daily cycle count and expected service life
- Connection voltage, network fault level and the network service provider's connection requirements
- Negotiated or proposed generating-system performance standards, including reactive capability, ride-through and frequency response obligations
- Intended market services — energy shifting, peak management, contingency or regulation FCAS — and any grid-forming requirement
- Protection philosophy at the connection point, including anti-islanding or transfer-trip arrangements
- Site design ambient temperature range, altitude, dust exposure, UV and wind region for structural loading
- Bushfire exposure, asset protection zone, vegetation clearance and the fire authority's requirements
- Fire detection, venting and suppression concept, and separation distances available on the site layout
- Foundation arrangement, site access route, permissible axle loading and available crane capacity
- Communication protocol, SCADA points list and metering and market registration arrangements
- Which Australian entity will act as responsible supplier for RCM, and the GEMS registration route for the transformer, together with delivery terms