Black humour aside, there is a certain truth to this saying when even bad energy stocks seem to be enjoying the boom created by high oil prices.

But there are some turkeys that can’t stay aloft. Part of the energy sector that has not soared is one of The Slug’s least favourite – the geothermal stocks.

Years ago, when so-called ‘hot rock’ technology was being promoted as the energy source of the future, The Slug let off a loud raspberry, which caused a few of the proponents to react angrily.

“What on earth would you know” was the common theme of the mail received by The Slug. “This is world-beating stuff. Australia is sitting on some of the hottest rocks in the world, and all we have to do is pump water down one hole, let it heat up, drawn the resulting steam and, hey presto, we bung that through a turbine, and out comes electricity.”

To which The Slug replied, “Oh yeah?”

Having hot rocks deep beneath the planet’s surface should not surprise to anyone with the most rudimentary understanding of geology – or who has read Jules Verne’s 1864 fiction classic about a journey to the centre of the earth.

But having established that rocks get hotter at depth, either because the centre of our planet is molten, or because of uranium, or thorium, enrichment in a layer of granite, the next questions become somewhat more difficult.

They include asking the people doing the drilling for the location of their hot rocks, particularly whether they are close to a potential energy market, and whether they can actually complete the cycle of water down and steam up in a way that is commercially viable.

For a while, The Slug was made to look a right goose. Hot rock stocks became the flavour of the month, governments offered geothermal exploration permits, and new hot rock floats popped up routinely.

Having been served a few slices of humble pie by the hot rock proponents but declining to eat it, The Slug reckons it’s time to return the favour.

And what better place to do that than by looking at how the stock market is treating hot rock turkeys (sorry, stocks). The answer is, not very well.

In fact, given that every other form of energy-related stock is booming, you might even say hot rocks have gone cold.

A step further, and it could be said that compared with oil producers and uranium explorers, the hot rocks industry is positively glacial.

Consider four specialist hot rock companies, purely for illustration purposes, of course. Market leader Geodynamics was trading around $1.84 at this time last year. Today it’s around $1.36. Green Rock has gone from 25c to 13c. Petratherm has slipped from 35c to 30c, and Geothermal Resources, one of the new boys on the block is down from 25c to 23.5c.

No prize for guessing who wins a price competition between the hot rock players and the oil stocks, or the uranium stocks.

True believers in hot rock technology and its future as an energy source will dismiss The Slug’s comparison of their industry with oil and uranium as unfair. Perhaps. But it is also getting to a time when a few more people will run a critical eye over a technology that sounds so simple in principle but seems to be so hard to deliver.

We might even get to a stage where someone rude says, “Enough hot air. Put up, or shut up!”