The California Public Employees' Retirement System (CalPERS) lost roughly 71% of its $468 million investment in a clean-energy and technology private equity fund - and won't explain how. The losses highlight growing concerns about the pension giant's private equity strategy, which relies heavily on opaque, illiquid investments and leaves taxpayers ultimately on the hook.

According to state records analyzed by the Center Square, the CalPERS Clean Energy & Technology Fund (CETF), launched in 2007, has seen its value fall from a total commitment of $468.4 million to $138 million as of March 31, 2025. That represents a loss of more than $330 million, even after paying $22 million in fees and costs to private equity managers.

CalPERS' overall returns for fiscal 2024–2025 were 11.6%, with public equities returning 16.8% and private equity 14.3%. The similar performance between the two asset classes has raised questions about whether the complexity and cost of private equity are worth it.