Taiwan and perhaps other Asian countries that successfully make stuff don't expose their industries to this, the government sets a fixed energy price for them rather than leaving them at the whim of speculators.

You don't have to, but you make more profit if you do. An energy producer that has the choice to sell energy for a lower price domestically or a higher price internationally will obviously choose the higher price, but you can make laws to make that illegal, if you want to.