Energy Storage System (ESS) refers to an energy system that integrates a grid connected PV system and battery system. It stores excess solar energy into a battery bank during the day to use when the sun stops shining. ESS can also supplement loads when higher demand occurs for short periods during the day.

In a nutshell, ESS allows for time shifting power, charging from solar, providing grid support as well as exporting power back to the grid. Many homes and businesses with existing solar systems can benefit from installing an ESS system. There still is a financial drawback as the systems are more longer term investments with a general estimated payback curve of 8 years currently.

Why ESS?

There are many practical benefits that supersede the cost of ownership for certain customers. Below an outline of good reasons to invest in Energy Storage Systems:

  • Electric vehicle owners
  • Much less or zero dependency on the power grid
  • Uninterrupted power supply in case of an outage
  • Less carbon emissions
  • Freezing future energy price increases
  • Balanced load and advanced protection against external power surges

ESS are not used in the below instances:

  • Stand-Alone/Off Grid systems – either with or without generator
  • Marine and Automotive systems
  • Inverter priority, also known as ‘Intentional islanding“ or ‘Ignore AC’ input systems

The table outlines some popular sizes for single phase Energy Storage Systems in terms of continuous inverter output in kW and battery storage in kWh. These systems are geared towards homes and business that already have solar installed. The systems we install utilise premium inverter and battery technology that are generally compatible with quality grid inverters such as Fronius, ABB, Solar Edge and SMA brands to name a few.

Three phase systems are more complex and have to be designed accordingly.

This is an example of a 24V UPS system with the following specifications:

3kVa Battery Inverter with 2.8kW LiFePO4 Battery (5 year warranty)
Victro MultiPlus 24/3000/70-16
Victron Color Control GX + Enclosure
UP2500, 24V 60Ah, 2.84kWh 3RU

Extras to consider:
Meter-board compliance (might need upgrading to connect to the grid)

Typical price range for a decent quality system: $7,995 to $9,495+

Stand-Alone systems, otherwise referred to as off-grid installations, can be considerably more complex than Grid Connect systems. Reliable Stand-Alone systems are not only dependent on equipment quality, but attention to detail in terms of system design and installation. We advised that Stand-Alone systems are designed at least 20% over required capacity to be future proof, as consumption is likely to increase over time. Volta offers its clients modular solutions where every aspect of the system us up-gradable especially on the storage side. We cater for any size system, from tiny homes to off grid businesses and mining operations.