* CSI300 +0.3 pct; SSEC +0.3 pct; HSI +0.9 pct
* Energy stocks +0.7 pct, merger announced
By Sue-Lin Wong
SHANGHAI, Feb 4 (Reuters) - China shares rose for a second day on Wednesday, pushed up by energy stocks after Chinese nuclear power firms announced plans to merge in a bid to boost offshore clout.
Shanghai Electric Power Corp Ltd said its parent company, China Power Investment Corp, had received approval to start work on a merger with State Nuclear Power Technology Corp (SNPTC).
Shanghai Electric Power Corp Ltd shares jumped 7.7 percent and the energy sub-index was up 0.7 percent.
The CSI300 index rose 0.3 percent, to 3,447.92 points at the end of the morning session, while the Shanghai Composite Index gained 0.3 percent, to 3,212.92 points.
In Hong Kong, the Hang Seng index added 0.9 percent, to 24,763.04 points. The Hong Kong China Enterprises Index gained 1.0 percent, to 11,890.42.
The financial sub-index rose 0.3 percent while banks dropped 0.3 percent.
"Blue chips like insurance and brokerages have begun re-adjusting and have already fallen 10 percent but are likely to fall even more," said Wang Weijun, an analyst at Zheshang Securities in Shanghai.
Baoshan Iron & Steel Co Ltd leapt to its 10 percent trading limit after it announced it was setting up a service platform firm with partners.
Wanda Cinema Line Corp hit its upper daily trading limit of 10 percent after Reuters reported its parent company Dalian Wanda Group was buying Swiss sports marketing company Infront Sports & Media AG.
China's only listed low-cost carrier Spring Airlines Co was up 0.9 percent and the company has more than doubled in value to $3.3 billion as investors scramble for a piece of a still-small industry set for massive growth in China.
China CSI300 stock index futures for February rose 0.3 percent, to 3,459.4, 11.48 points above the current value of the underlying index.
The index measuring price differences between dual-listed companies in Shanghai and Hong Kong stood at 123.98.
A value above 100 indicates Shanghai shares are pricing at a premium to shares in the same company trading in Hong Kong, and vice versa.
Total volume of A shares traded in Shanghai was 13.69 billion shares, while Shenzhen volume was 8.91 billion shares.
Total trading volume of companies included in the HSI index was 1.0 billion shares.
Reporting by Sue-Lin Wong; Editing by Simon Cameron-Moore and Jacqueline Wong