Australia's federal government recently blocked the sale of the nation's largest electrid grid, after a chinese and Hong Kong holdings company attempted to purchase a controlling stake. The government bowed to pressure from opponents of the deal, who said they were giving away control of their power grid to another country.
There isn't any word that I don't know in this sentence, but it's hard to understand what it means.
Does "opponents" here mean "a Chinese and Hong Kong holdings company" cause they are the ones who are rejected?
And does "power grid" here mean "the nation's largest electrid grid (company)"? Then what does it mean by "give away control of their power grid to another country"?