SAN FRANCISCO — The ambitious founders of Google, the popular search engine company, have set up a philanthropy, giving it seed money of about $1 billion and a mandate to tackle poverty, disease and global warming. But unlike most charities, this one will be for-profit, allowing it to fund startup companies, form partnerships with venture capitalists, and even lobby Congress. It will also pay taxes. One of its maiden projects is bound to get attention. According to people briefed on the program, the organization, called Google.org, is aiming to develop an extremely fuel-efficient, plug-in hybrid car engine that runs on ethanol, electricity and gasoline. The philanthropy is consulting with hybrid engine scientists and car manufacturers, and has arranged for the purchase of a small fleet of cars with plans to convert the engines so that their gas mileage exceeds 100 miles per gallon. The goal: reduce dependence on oil while alleviating the effects of global warming. Google.org is drawing skeptics for both its structure and its ambitions. It is a slingshot compared with the artillery of charities established by older captains of industry. Its funding pales next to the tens of billions that the […]