Final answer:
The Charles David Keeling apartments at UC San Diego and the Cogeneration plant at UC Irvine are the only two residences in the UC System with LEED Platinum certification, indicating top-level sustainability and energy efficiency practices.
Step-by-step explanation:
The two residences in the UC System that have LEED Platinum certification are the Charles David Keeling apartments in UC San Diego and the Cogeneration plant in UC Irvine. LEED Platinum is the highest level of certification granted by the Leadership in Energy and Environmental Design (LEED), a globally recognized symbol of sustainability achievement. It measures a building's environmental impact, energy efficiency, materials used, and more. Both residences achieved this status through various sustainable practices like energy-efficient construction, waste reduction, and water conservation efforts.
Learn more about LEED Platinum Residences