The Commerce Department said on Wednesday it would investigate whether Chinese companies sell solar panels in the United States at unfair discounts and receive illegal government subsidies.

ReneSola Ltd. reined in its guidance for third-quarter revenue and shipments, while noting it expects to post a loss for the period due to continued weak demand and industry oversupply.

Chinese solar-equipment makers said tariffs sought by US competitors would make it harder to expand the use of renewable energy.

Yingli Green Energy Holding Co. and Renesola Ltd., two Chinese solar companies, reduced their forecasts for shipments and cut the estimated values of their inventories.

China's Trina Solar Ltd slashed its sales estimates for solar panels on Thursday because of weak European demand and said declines in panel prices would shrink its profit margins.

SunPower Corp. and First Solar Inc., the two largest US solar manufacturers, will reorganize as falling prices and increased competition from China drive down sales.

India's solar power costs could fall by more than 40 percent by 2015, allowing the industry to compete against domestic oil and gas firms without the help of state subsidies, the head of Lanco Solar told Reuters on Wednesday.

In order to promote solar power, the government is subsidising the technology. Besides, efforts are also on to encourage people to get into using the solar energy equipment.

GOVERNMENT help for solar power was supposed to be a triple play: jobs at a time of dire short-term need; incubation of an American industry sure to be important on a global scale in the next few years; and a long-term reduction in climate-changing pollution.

A recent report from the USA has found return on investment from solar power is higher than any other renewable energy source.

Installed capacity in Italy is expected to reach 12.5GW by the end of the year, according to the chairman of the Italian Photovoltaic Industry Association (GIFI), Valerio Natalizia.

The big number is 50. When companies can produce solar photovoltaic modules for less than 50瞽 per watt, solar energy will be able to compete directly with coal.

Executives of the failed solar- panel maker Solyndra LLC are refusing to answer questions at a congressional hearing today, a sign that the first serious financial scandal of the Obama administration has arrived.

High quality global journalism requires investment. Please share this article with others using the link below, do not cut & paste the article. See our Ts&Cs and Copyright Policy for more detail. Email ftsales.support@ft.com to buy additional rights. http://www.ft.com/cms/s/0/e43569d4-e30f-11e0-bb55-00144feabdc0.html#ixzz1YYPv5fmw The US solar power industry employs more than 100,000 people, twice as many as it did two years ago and more than the steel industry or coal mining, the industry's trade group has said.

Solar Frontier will be starting to put its Kunitomi plant to serious work as it recently closed a deal to supply over 30MW of its CIS solar modules to solar projects in India by the end of 2011.

Developers installed 69% more US solar power capacity in the second quarter than a year earlier, led by commercial and government projects.

China's solar power firms are emerging as the industry's dominant force after the collapse of foreign competitors, but the new market leaders are already struggling with low prices and overcapacity.

The same market forces that doomed Solyndra, the solar cell manufacturer that received $528 million in government loans and then went bankrupt, could imperil other manufacturing ventures that have received loan guarantees from the Energy Department, energy experts warned this week.