Railway Minister Suresh Prabhu on Saturday underlined the need for the Indian Railways to look beyond traditional sources of revenue.Prabhu said advertisements could be a big source of revenue for the railways and added that new equity models between the central government, state government and the private sector were being worked out to cater to the investment needs. "The railways needs structural changes and needs investment. The railways is suffering only because of lack of investments. But at the same time we must not lose sight of issues -- customer services, freight punctuality etc," said Prabhu at the 89th annual general meeting of Ficci here. Pointing to the rising cost of operations and the extreme low freight growth, Prabhu said the railways was working on improving its non fare revenue. "Traditionally railways have relied on freight and fare for revenue but that is not going to work because the cost of operations has gone up significantly. The biggest burden of the pay commission is on railways, the largest employer in the country. "Moreover, the growth of freight has been extremely low this year," he said. Talking about private participation, Prabhu said the railways have got two big ticket investments -- one from US-based GE and another from French multinational Alstom -- in the field of locomotive manufacturing. "The orders will be to the tune of Rs 20,000 crore," he said.