When Li Ka-shing – one of one of the world’s most successful asset traders – sells anything, the question is always why. For Hong Kong Electric, the first of two big spin-offs expected from Mr Li this year, the answer looks simple at first glance. The sale will help fund juicier investments at Power Assets Holdings, HK Electric’s parent, whose businesses range from keeping the lights on in southern Australia to distributing electricity to the London Underground. But the smarter question is: why now?

Mr Li is creating a business trust for between 51 and 70 per cent of HK Electric, one of just two utilities supplying the territory. PAH shareholders vote today, but since 39 per cent of the votes belong to Mr Li’s empire, it would seem a done deal. PAH should reap between $2.7bn and $4.8bn, after taking out $2.7bn in loan repayments. That is a decent sum for shopping.

Maybe the timing is as simple as Mr Li’s having his eye on a particular bargain, or that PAH’s international business is now bigger than its home base. There may be a regulatory angle too: direct ownership by the Hong Kong public, not through PAH, would likely make it politically harder to cut HK Electric’s current 9.9 per cent regulated returns when renegotiation looms. Limiting Mr Li’s income is one thing, hurting hard-working Hong Kongers is another.