Some Taiwan-based solar cell makers have raised price quotes or given verbal notification to customers that prices will hike in June, according to industry sources. In the last week of May, the spot price of solar cells produced by Taiwan-based makers increased 1.5% to US$1.37 per Watt.

In the first three weeks of May, solar cell prices slipped modestly, and most market observers expected prices to remain stable or fall in June with the pending subsidy cuts by the German government. Hence, many solar module makers were shocked by the sudden price hike and demands to increase quotes next month, the sources said.

Sources from solar cell maker Gintech Energy said they believe the current price increase is caused by cell makers taking advantage of module makers and system installers that are rushing to beat Germany's feed-in-tariff slash on July 1.

Solar cell prices will not rise beyond the first two weeks of June, the sources said, since cells to be used in pre-July solar systems must be shipped out by mid-June.

Some industry observers credited the price jump to Simon Tsuo, chairman of Taiwan-based solar cell maker and a well-respected figure in Taiwan's solar industry, who last week commented optimistically about the solar sector in the second half of 2010.

His views are considered by many as a barometer of the solar cell market.

Tsuo said that previous concerns about double booking are no longer an issue, and Motec is still seeing continuous strong demand from customers in Europe and the US. Orders from other regions should keep shipments stable in the third quarter, and demand will once again spike in the fourth quarter with another round for subsidy reductions looming in early 2011, he added.