If a week is a long time in politics, it is an age in business, especially for those sectors of the economy exposed to political volatility.

Just ask the listed electricity companies, whose share prices are still wearing the effects of the single buyer policy the Labour and Green parties launched one year ago.

Take Monday 12 May as an example. In an otherwise buoyant market, with optimism running high ahead of the announcement that the government’s books were set to return to the black, the partially listed electricity stocks were a facing rougher chop.

Meridian Energy was flat, Genesis Energy declined 0.3 per cent and Mighty River Power chalked up a 2 per cent drop on the day.

The share movements had little to do with the wholesale electricity market (where prices were pinging around the middle of the recent trading band), but the prospect that a Labour/Greens coalition might just be gaining momentum ahead of the September election.

A share market analyst was quoted by financial newswire BusinessDesk as saying this sector was likely to remain volatile until the election was decided. This high level of uncertainty contrasted sharply with the air time the opposition parties have given to their own policy recently: almost zero.

What this shows is that the political machinations do not occur in a vacuum, and can generate unintended consequences quite a ways down the track even as the ardour for that particular policy dies down.

This is not to say that the opposition are wrong to express concern about rising power prices – that is essentially what our democratic system is there to do. But there needs to be a greater awareness of the potential risks when policy ideas are bandied around.

For example, in the electricity sector, the political risks are not just borne by those who own shares in the partially privatised power companies, but by almost every working age New Zealander with a KiwiSaver account, as a part of their retirement savings are likely invested in the local power sector.

Plus, there is no consensus within the industry that the proposed single buyer model will lower power bills.

On a broader level, the political volatility in the electricity sector raises an important question that needs to be asked of every election promise, namely what spill-overs will linger long after the rhetoric is dead?