Network trials solid-state hydrogen storage in 100 pct renewable stand-alone power system

A 100 per cent renewable stand-alone power system made up of solar PV and an innovative hydrogen storage solution is being trialled on the fringes of the Essential Energy grid, after being installed by Tempo Australia.

Tempo said on Monday that it had been awarded “Practical Completion” on the Stand-Alone Power Supply (SAPS), that includes the company’s greenHy2 system based on GKN hydrogen storage technology.

The heart of the system, installed in a remote location a three-hour drive north of Sydney, is solid-state metal hydride hydrogen storage that can store almost half a megawatt-hour of electricity and more than 40 days of forecast storage for the facility.

Essential Energy began investigating the use of SAPS – usually solar with battery storage and back-up diesel – on its New South Wales and south Queensland grid back in 2018, and then ramped up the process after the Black Summer of bushfires in 2019-20.

Originally, the distribution network company looked into SAPS as a way to provide temporary power while restoring poles and wires, but these days they are seen as a long-term off-grid power solution for customers whose properties are located on long powerlines, at the grid’s edge.

DNSPs like Essential Energy have come to recognise the many benefits SAPS offer over traditional poles and wires in some parts of the grid, including a more reliable and resilient supply for customers, less costly infrastructure maintenance, and reduced environmental impact.

Recent rule changes made by the Australian Energy Regulator aim to support networks in taking more customers “off-grid”, through a streamlined waiver process that weighs the risks to market competition against the benefits to consumers and the broader grid.

As noted above, SAPS rolled out to customers by network companies usually combine solar, battery storage and back-up diesel generators.

In this instance, however, Essential Energy is testing out hydrogen storage technology, and its potential eliminate the need for any back-up fossil fuels at all, by creating a reliable and 100% renewable energy supply.

The GKN developed technology uses a metal alloy powder from hydrides, compacted into high-density pellets, to create an efficient material to store hydrogen as a solid, rather than a gas.

Tempo says this method of storing hydrogen is considered the safest and most efficient available, enabling low pressure (max 40 Bar), ambient storage with a volumetric energy density far greater than that of lithium-Ion Batteries and compressed (liquid) Hydrogen at 700 Bar.

The storage is fed directly from a hydrogen electrolyser and, in turn, directly feeds a fuel cell, both without recompression, Tempo says.

The companies say the system, which includes a state of the art digital monitoring and operating platform with detailed data analysis, will be monitored for performance over the coming year.

Tempo says the digital platform provides real time performance of the SAPS and includes artificial intelligence to optimise it over time.

ASX-listed Tempo, an engineering and construction contractor and asset manager, has been shifting its operations further into the renewable energy sphere since 2019, when it made a shaky start on its first solar farm project in Victoria.

Its website describes its metal hydride storage solution as “the most reliable and secure hydrogen storage solution on the market,” using components that are 100% recyclable, and offering a 15-plus year lifetime and minimal capacity loss.