Ford Motor Co. Chair Bill Ford Jr. talked up the company’s commitment to the environment yesterday at its annual shareholders meeting. Several stockholders at the meeting charged that the company is not doing enough to curb emissions of greenhouse gases, but their proposal to require the company to disclose its emissions and its lobbying efforts against climate change regulations was overwhelmingly defeated. In other car news, Nissan has unveiled an early prototype of an eco-friendly car powered by a fuel cell that converts liquid methanol into electricity. The company plans to continue developing its technology independently rather than joining one of two larger industry alliances working on green cars.