ClimateBiz: The city of San Francisco is embarking on a pilot project to turn brown waste grease, known as FOG, in biofuel with help from $1.2 million in state and federal grants that will fund a public-private partnership with Philadelphia company BlackGold Biofuels and engineering firm URS Corp. The plant will recycle the waste formed by used cooking fat, oil and grease, or FOG, that melds with food scraps. FOG is a bane for commercial kitchens, which capture the stuff in grease traps …