Ford Motor Co. hopes to green its image today by announcing plans to increase the fuel economy of its SUV fleet by 25 percent, or about 5 miles per gallon, over the next five years. Ford now sells about 800,000 SUVs a year, and its 3.5-ton Excursion, the world’s biggest SUV, averages just 12 mpg. The company hopes that better fuel economy will attract more customers and boost its sales numbers so it can avoid raising prices to pay for the improvements. Ford plans to increase efficiency by using lighter-weight materials and making more efficient engines and transmissions. While enviros are generally critical of all SUVs, John DeCicco of the American Council for an Energy-Efficient Economy praised Ford’s move as a significant step forward.