Mr Underhill said it was the first education building in New Zealand to attain 6 Green Stars, the highest possible rating.
Judges said the building was technically excellent and genuinely cutting-edge, marking the first time passive annual heat storage had been used in New Zealand. The project was also highly commended in the Community Award category.
Te Mirumiru is also rich in references to Ngati Hine icons such as the tuna (eel), the waka, and the eponymous ancestor Hine-a-Maru.
Architect Phil Smith told the Advocate he wanted to create a genuinely Maori building, not simply a western building overlaid with Maori carvings. It was based around the concepts of kaitiakitanga (guardianship) and Papatuanuku.
Its womb-like shape and single entrance, a cut in the earth of its northern face, represented Hine-a-Maru giving birth by Caesarean section some 600 years ago.
The EECA (Energy Efficiency and Conservation Authority) Awards are held every two years to celebrate organisations and individuals demonstrating excellence in energy efficiency and renewable energy. Collectively this year's awards entrants will save or generate energy worth about $100 million over the projects' lifetimes and reduce or avoid 200,000 tonnes of CO2 emissions.