Rising up from the Deep… Taupo’s Natural Extraction a World-first
Taupo’s rising popularity isn’t just founded upon its stunning landscape – things are causing a stir underground too. In a world-first venture the Ohaaki Power Station has developed a geothermal silica processing plant, extracting silica direct from its bubbling waters.
The power station, operated by Geo40, in partnership with Contact Energy and local iwi Ngati Tahu, is set to extract and export over 10,000 tonnes of silica annually through its newly created plant.
As global market demand heats up for silica – over one million tonnes a year and rising – and geothermal growth steadily increasing in New Zealand, the business potential country-wide for silica production is huge.
Not only is Ohaaki putting New Zealand on the silica map, it’s also leading the way in natural processing means – traditional as opposed to man-made. Because the geothermal reservoir is already heated, the silica is naturally dissolved, making it better for the environment and for those workers involved with the extraction process.
So how does Ohaaki silica take its form? Through a unique filtration system, the silica laden boiling water is cooled, filtered, washed and concentrated and the final product can either resemble a powder-like product or a liquid-like version of colloidal silica. The silica can then be used to create products across many an industry including sporting goods – think golf clubs – house wares – think paint – even medical products – such as implants.
Not only is the extracted silica a win-win in product development, it’s also a win-win for the station’s day-to-day power operations. Removal of the silica from the geothermal pipes means less wear and tear on infrastructure and fewer hours and dollars spent repairing equipment. Plus, the silica-free pipes also allow for greater heat extraction from the geothermal fluid, speeding up running time – a huge plus for energy provider Contact Energy.
Whilst the Ohaaki locals and Ngati Tahu Tribal Lands Trust will receive both financial and social benefits from the silica processing, the surrounding waterways will also become much clearer. The silica-free water is being pumped back into the sacred Ohaaki Ngawha hot springs post-processing – restoring both beauty and renewed optimism back into the community.