Ampt selected for Australian solar storage project

Ampt has been selected to provide string optimiser technology for a hybrid solar and battery development in Victoria, Australia, combining 8.2MWdc of photovoltaic generation with 20MWh of energy storage and 4.95MWac of power conversion capacity.

The project will use the company’s Direct-to-Battery architecture, which connects photovoltaic strings through optimisers to a DC bus shared with the battery and its inverter. Ampt says the arrangement can reduce equipment costs, increase energy collection and provide the rapid power response required for electricity grid services.

Announced on 22 October 2026, the equipment selection concerns a specific medium-sized renewable installation rather than a general technology partnership. Ampt has not identified the project’s developer, precise location, construction timetable or planned commercial operation date.

The combination of solar generation and battery storage is intended to allow electricity collected during the day to be exported or stored for later delivery, depending on operating conditions and commercial arrangements.

Ampt’s electrical configuration differs from an AC coupled solar and storage installation in which the photovoltaic array and battery typically use separate power conversion equipment connected through an alternating current system.

In an AC coupled arrangement, solar electricity is converted from direct current to alternating current before being exported or used through the site’s AC electrical infrastructure. Charging the battery may require another conversion stage to return electricity to direct current.

DC coupling allows photovoltaic generation and storage to exchange energy before conversion to alternating current for the grid. This can reduce certain conversion losses and enable the battery to absorb solar electricity that exceeds the site’s immediate export capability.

Ampt’s architecture connects string optimisers to the shared DC bus between the battery and battery inverter. The company says this avoids separate central DC/DC converters and dedicated photovoltaic conversion equipment used in some alternative configurations.

The design does not mean that the installation has no power electronic converters or transformers. String optimisers perform electrical conversion and control functions, while equipment required for connection to the distribution network will depend on the selected inverter and connection voltage.

Photovoltaic modules produce different amounts of power according to sunlight, temperature and their individual operating characteristics. Partial shading, soiling and module degradation can create mismatches between the electrical outputs of different parts of an array.

These mismatches can reduce electricity production when modules or strings are constrained to operate at conditions that do not maximise their available power.

Ampt’s optimisers are intended to manage string output so that the photovoltaic array can operate more effectively while delivering electricity to the voltage conditions required by the shared DC system.

Battery voltage also varies with operating conditions and state of charge. The string optimiser arrangement is designed to accommodate those variations, maintaining controlled power transfer without requiring all photovoltaic equipment to operate at the battery’s changing voltage.

The electrical design determines how effectively solar power can be allocated between storage and export. When photovoltaic generation exceeds the available AC conversion capacity, an appropriately controlled battery may absorb surplus electricity if sufficient charging capacity and unused storage are available.

That capability can reduce energy lost through conversion-related export restrictions. It does not guarantee that all otherwise curtailed generation will be captured, because charging power, state of charge and other operating constraints still apply.

The Victoria project has a nominal photovoltaic rating of 8.2MWdc and an AC conversion rating of 4.95MWac, giving a DC-to-AC ratio of approximately 1.66.

A higher DC rating can improve inverter utilisation during periods of lower sunlight. During stronger generation conditions, output may exceed the available conversion capacity, making storage operation and system control important to how much electricity can be used.

The 20MWh storage rating describes the battery’s nominal energy capacity rather than its maximum charging or discharging power. If 4.95MW could be delivered continuously from storage alone, 20MWh would correspond to approximately four hours of nominal output before operating losses and capacity restrictions.

However, Ampt has not disclosed the battery’s independent power rating or confirmed that the entire AC conversion capacity can be supplied from storage for that duration. The calculation should not be treated as a guaranteed operating specification.

The installation is intended to support participation in Australia’s contingency Frequency Control Ancillary Services markets, which procure responses to electricity system disturbances.

A frequency disturbance occurs when the balance between generation and demand changes sufficiently to move system frequency away from its intended operating range. Batteries can respond rapidly through inverter controls by adjusting output or charging demand.

Qualifying for these services requires equipment and control systems capable of delivering the specified response under applicable market and testing requirements. Equipment selection alone does not confirm that the project has completed those tests or secured registration.

The published announcement does not identify the final battery management system, inverter supplier or market participation arrangements. The operating characteristics will therefore require confirmation as the project progresses through installation and commissioning.

Ampt also claims the architecture can lower balance of system costs by reducing duplicated conversion equipment and electrical cabling.

Those potential savings depend on project design, cable routing, equipment selection, installation conditions and the comparison used. No verified cost reduction or measured increase in lifetime electricity production has yet been released for the Victorian installation.

The project falls within a segment receiving increasing attention from Australian infrastructure financiers. In August, the Clean Energy Finance Corporation committed A$100 million to the Distribution Connected Accelerator Program, supporting the development of hybrid solar and battery projects typically rated up to 5MWac.

With 4.95MWac of conversion capacity, the Victorian project is comparable in scale to installations targeted by that programme. Its participation in the financing initiative has not been announced and should not be assumed.

Medium-sized renewable installations can connect closer to electricity demand than some large transmission connected projects, although the value of such connections depends on local network capacity and operating limits.

A battery may be able to alter export patterns and reduce power flows during certain periods, but it can also create additional demand while charging. Whether this benefits the network must be established through connection studies and operating arrangements.

Ampt’s selection establishes the intended conversion architecture for the project, while construction, grid connection and frequency service qualification remain outstanding. Its claimed economic and operational advantages will need to be assessed against the installation’s eventual performance.