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In a notable achievement for New Zealand's renewable energy sector, Ecogas has been awarded the AD Hero of the Year at the 2025 AD and Biogas Industry Awards. This recognition underscores the impact of their pioneering anaerobic digestion facility, located in Reporoa, which is the country’s first commercial-scale energy plant powered by food waste.

Annually, the facility processes approximately 75,000 tonnes of organic waste sourced from council kerbside collections as well as commercial and industrial food producers. This initiative not only diverts over 11,000 tonnes of carbon dioxide from the atmosphere but also aligns with New Zealand's ambitious goal of achieving net-zero carbon emissions by 2050.

Peter McClean, CEO of Ecogas and its parent company Pioneer Energy Group, attributes this success to robust partnerships and a collective commitment to reducing organic waste in landfills. In a competitive landscape marked by limited policy support and financial incentives, he expressed gratitude towards their partners, councils, and commercial customers for their unwavering support.

Officially inaugurated in October 2022, the facility generates biogas and digestate biofertilizer. The biogas produced is upgraded into biomethane, which is then injected into New Zealand's gas grid. Additionally, carbon dioxide is provided to a nearby greenhouse, enhancing tomato crop growth.

To address health concerns related to the co-mingled food waste feedstock, the facility employs the HRS Digestate Pasteurisation System (DPS). This innovative system treats digestate by neutralizing pathogens and weed seeds, ensuring the biofertilizer's safety for agricultural applications. Unlike conventional pasteurization methods that often waste energy, the HRS DPS optimizes energy recovery by transferring heat from pasteurized sludge to unpasteurized sludge, significantly reducing overall energy consumption.

The automated system heats digestate to over 70°C for one hour before cooling, achieving an efficient kill step for pathogens such as Salmonella, Staphylococcus, and E. coli. The resulting treated digestate emerges as a safe biofertilizer, with improved nutrient quality and reduced odors. Installed in February 2022, the compact design of the HRS DPS consists of two interconnected frame modules, allowing for efficient space utilization.

Alzbeta Bouskova, General Manager at Ecogas, elaborated on the choice of the HRS DPS, highlighting their adherence to the UK PAS110 digestate standards to ensure the biofertilizer's safety and quality. Ella Taghavi, Sales Engineering Manager at HRS Heat Exchangers, emphasized the significance of the Reporoa facility for New Zealand's bioenergy landscape, noting that efficient pasteurization not only facilitates the safe use of digestate as a renewable fertilizer but also contributes to the nation's renewable energy objectives.