"The industry is growing faster than a sustainable rate. That is why prices are falling so much," said Plinio Nastari, president of Datagro consultancy.

With expected demand for 720 million tonnes of cane by 2013/14, the sector should not grow more than 7.3 percent per year to avoid worsening the current oversupply, Nastari said late Monday after a sugar and ethanol seminar.

But Brazil's cane crop has risen an average of 9.9 percent each year since 2000, boosted by increasing ethanol demand.

Datagro projected demand for cane is currently higher the one expected by the consultancy a few years ago, but investments in new mills have surpassed what was forecast, and are at an exceedingly high level, Nastari said.

There are 138 projects of new mills. The building of 79 of them are highly probable, while 30 are moderately probable and 29 will not likely advance out of planning, he added.

"I think there is still not any (international ethanol) market. We're all working irrationally. There is not any strategy either from the private sector or from the government," said Roberto Rodrigues, director for the Inter-American Ethanol Commission, also attending the seminar.

"How much ethanol do we want to produce? Nobody knows," Rodrigues said, adding that the potential market is huge, however.

GOVERNMENT WORRY

Sugar and ethanol prices have fallen around 35 percent since the beginning of the 2007/08 cane crop, and the drop's effect on the industry is raising concerns also in government.

"The market will not grow if we do not organize all parts of the production chain in a way to keep security and stability (in supply)," said Manoel Bertone, Production and Agroenergy Secretary in the Agriculture Ministry.

He said the disorganized way the market is growing will not be in line with the rise in demand, what could lead to even lower prices.

"Besides that, if we do not have a regulatory basis, possibly no country will buy ethanol from us," he said.

Bertone ruled out intervention in the sector but defended a dialogue between producers and the government.

The launch of flex fuel vehicles in 2003 made it harder for analysts and producers to make demand projections, as consumption in this case depends totally on the relation between ethanol and gasoline prices.

Normally if the biofuel is 60 to 70 percent the gasoline price at stations, ethanol is a better option for flex-fuel car owners.