After briefly testing their long-term trend lines, solar sector exchange traded funds rallied Wednesday, strengthening on the surge in Trina Solar (NYSE: TSL) shares.

The Guggenheim Solar ETF (NYSEArca: TAN) gained 4.8% Wednesday while the Market Vectors Solar Energy ETF (NYSEArca: KWT) rose 3.4%. Nevertheless, TAN is still down 15.1% and KWT is 13.1% lower over the past three months.

Trina Solar jumped 29.3% Wednesday, the largest intraday increase since February 2012, after the company revealed sales increased 71%, reports Ehren Goossens for Bloomberg.

The company stated that net income over the first quarter was $26.5 million – the third straight profitable quarter, compared to the year-earlier loss of $63.7 million.

“We have made further progress adjusting our sales mix to achieve relatively stable” prices, Chief Executive Officer Gao Jifan, said in a statement.

Trina shipped 558 megawatts of photovoltaic panels in the first quarter. Looking ahead, the company expects to ship 950 megawatts to 1,010 megawatts in the second quarter and 3.6 gigawatts to 3.8 gigawatts this year.

Solar stocks have been weakening as investors feared China would not be able to meet its 14.5 gigawatts target for installed solar generating capacity this year, Reuters reports. [FSLR, Solar ETFs Dim As Investors Ditch Momentum Stocks]

“I think the company helped alleviate some of the concerns about China demands in the second half of the year,” Angelo Zino, an analyst with S&P Capital IQ, said in the Reuters article.

Shares of other rival solar companies also strengthened on the positive China outlook, with Yingli Green Energy (NYSE: YGE) up 11.1% and ReneSola (NYSE: SOL) up 12.6%.

Looking under at the aforementioned solar ETFs, Trina Solar makes up 3.4% of TAN and 2.5% of KWT. SOL is 1.5% of TAN and 1% of KWT. YGE is 2.4% of TAN and 1.3% of KWT.

Guggenheim Solar ETF

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Max Chen contributed to this article.