Native shrubs and solar panels working in tandem in South Australia

From pv magazine Australia.

South Australian utility SA Water is planting almost a ton of native grass and saltbush seed under thousands of solar panels across the state to secure the return of native scrub vegetation and local jobs.

South Australia’s largest water and sewerage company announced in January it was planning to invest more than AU$300 million (US$212 million) in solar and energy storage this year and the Covid-19 pandemic has failed to derail those plans.

Perhaps inspired by the utility’s resilience – and the same characteristic of indigenous vegetation – environmental conservation group Succession Ecology has partnered with SA Water to ‘re-vegetate’ low-growing grasses and saltbush species at five regional pump stations which feature ground-mounted solar.

The locations, which include Port Pirie, Port Augusta, Whyalla and Peterborough, are among the 35 SA Water facilities in the process of having 500,000 solar panels installed for a total generation capacity of 242 GWh per year, when finished.

Natural partnership

A Succession Ecology director and re-vegetation consultant said the beauty of the native varieties is their “ability to create a native biodiversity, attracting insects and birds, with the vegetation only reaching knee height [so] as to not impact solar performance.” 

As SA Water vegetation specialist Shaun Kennedy noted, the plantings will also provide diverse, native ground cover beneath solar arrays to help a long-term strategy for weed and dust suppression and reduce heat build-up in the panels.

The result, then, is a technological and ecological partnership. Airborne dust is a sworn enemy of PV modules, as any foreign particle or substance on the glass face of a panel impedes or restricts UV light absorption through soiling. When pv magazine Australia spoke with panel cleaning business Australian Solar Maintenance last year, the company said solar yield losses attributable to soiling varied but could exceed 10% in some months, particularly in dusty locations such as Port Augusta. 

As an added bonus, the project enabled Succession Ecology to employ four people for seed collection.

The headline to this article was changed on 21/07/20 because the projects form part of an AU$300 million scheme, rather than having a 300 MW generation capacity, as previously stated.