. >> gabriella lozano owns a small cafe in san francisco's mission district. she composts everything. >> i'm a strong believer that i'm doing what i can, and the best that i can. >> what she's doing here on a small scale... is part of a much bigger picture. >> you look at what she's doing here in terms of diverting waste away from landfills and creating a recycling type of circuit here with everything that happens at l's and that's what we have to look to. >> inspired by western europe, san francisco offers owners like lozano financial incentives to compost. >> a lot of these small business are actually doing it for economic reasons... it lowers their bill for recycling, their garbage bill over all... money is a way to motivate people. >> but it's not the only motivator... >> when the food waste is in the landfill it decomposes, and it generates methane gas and methane is a very potent greenhouse gas. >> john hake is a civil engineer who runs the resource recovery program in the east bay, where they combine solid food waste with liquid wastewater to create fue