Electricity prices: 82% higher her than in Hong Kong

Paul Chan wrote to the Straits Times Forum about our electricity charges. Hong Kong residence pasy 17 cents per nit. Singaporeans pay 31 cents - 82% higher. Electricity in Singapore is more expensive than in USA or France.

What is happening? I recall these events but cannot remember the details:

1. Our power plants sold by Temasek to foreign shareholders?
2. Singapore hedged the price of oil, and are now stuck with the higher contracted prices?

I like to invite the knowledgeable people to put some details into what is happening here. You can also help to search Google for the facts.