SELECT dirty_electric_grid_rocky_mountains__denver_ FROM table_23840623_4 WHERE clean_electric_grid_california__san_francisco_ = "160 g/mi (99 g/km)"
Apa kisi -kisi listrik Dirty Rocky Mountains (Denver) untuk kendaraan dengan Clean Electric Grid California (San Francisco) dari 160 g/mi (99 g/km)?
CREATE TABLE table_23840623_4 (dirty_electric_grid_rocky_mountains__denver_ VARCHAR, clean_electric_grid_california__san_francisco_ VARCHAR)