Conservative deputy leader Michael Ancram has warned those hoping to replace Michael Howard that they are ignoring the issue of energy.
Michael Ancram has not yet declared his hand
Describing it as Britain's "greatest crisis", Mr Ancram told leadership hopefuls energy must be debated.
He said an "energy audit" was necessary with oil and gas reserves dwindling, and coal and nuclear unpopular.
Britain must consider more nuclear power, alongside increased investment in areas like biofuels, he said.
Mr Ancram - who was forced out of the last leadership race in 2001 at the first hurdle - has not revealed whether he will stand this time.
He said: "It is astonishing that the Conservative leadership campaign has proceeded so far without any real mention of what is almost certainly the greatest crisis facing our citizens in the next generation."
With oil prices rocketing and even the price of coal having endured highs because of massive demand in China and India, the energy debate is becoming prominent.
Mr Ancram added: "Some politicians dismiss the energy crisis as a hyped green agenda. It is not.
"Our political system will be severely challenged the day a British citizen turns on the light switch and nothing happens or switches on the kettle and the kettle stays cold."
Despite recognising the potential of nuclear power and biofuels, Mr Ancram stressed the importance of conservation.
"We need an urgent 'energy audit', both of our potential and import requirements.
"We need to know the finite limits of our own energy and begin urgently to develop alternatives, including conservation.
"The one thing we cannot do is to pretend that energy is not a matter for urgent debate."