IT was a nightmare scenario. A foreign leader with totalitarian tendencies turns off the gas supplies to a neighbouring country and triggers a wave of panic about energy security across Europe. Russian President Vladimir Putin's decision to stop sending gas to Ukraine for four days last week sent a chill through the European energy market. There was much talk about the risks of relying on foreign suppliers and the dangers of "energy imperialism".

The underlying concern was that the fuels we all use to heat our homes, cook our food and move us around could become increasingly vulnerable to the whims of powerful political leaders and multinational companies. That worries many.

The Russia-Ukraine gas crisis also prompted nuclear enthusiasts, such as the former energy minister Brian Wilson, to pipe up. It showed, they claimed, that Prime Minister Tony Blair was right to launch a review of energy policy this year aimed at resurrecting the nuclear power industry.

But what, in reality, has the crisis taught us? Its lessons, inevitably, are more complex, more subtle and - perhaps - less discomforting that they might at first appear.

Political and commercial interference in energy supply is not, of course, a new phenomenon. Historians say that one of the reasons why Japan bombed Pearl Harbour in 1941 was because the US had cut oil supplies to Japan.

Oil was also behind a 1953 coup in Iran by the US and the UK, when they overthrew a democratically elected leader, Mohammed Mossadegh.

And in the 1970s Opec, the cartel of mainly Middle East oil producers, memorably jolted the developed world by deliberately restricting oil supplies.

In more recent times, concerns about the future security of oil and gas supplies was seen by many as a factor in the US and UK decision to invade Iraq. It probably also spurs current diplomatic anxiety about the ambitions of Iran under its new fundamentalist leadership.

"Energy imperialism is a fact of the modern world, " said Daniel Litvin, a former policy adviser to the mining multinational Rio Tinto, and author of the book Empires Of Profit: Commerce, Conquest And Corporate Responsibility.

In the past, he argued, governments and companies have often been guilty of supporting corrupt or undemocratic regimes in order to secure energy supplies. He warned that similar mistakes could be made in the rush for oil in west Africa and around the Caspian sea.

"There is a risk that we will go back to old imperial patterns of behaviour when companies, along with governments, backed undemocratic regimes to ensure short-term stability, but sowed the seeds of long-term instability, " Litvin told the Sunday Herald. He pointed out that US attempts to install energyfriendly regimes in Latin America had recently resulted in two countries' presidents threatening to turn the tables. Venezuela's Hugo Chavez has talked of interrupting oil shipments to the US, while Bolivia's newly-elected Evo Morales has vowed to seize control of gas reserves from multinationals.

So by playing politics with the gas pipelines through Ukraine, Russia was just doing what many other countries have done before: using energy as a political weapon. The problem for western Europe is that this time it could have been the victim, since Ukrainian pipes carry gas to Germany, Italy, Turkey and France.

This is an issue that is not going to go away, because the 25 countries in the European Union (EU) possess so few of the world's fossil fuel resources. Between them they have 7.3-per cent of the coal, 2-per cent of the gas and 0.6-per cent of the oil.

That is why the EU expects that by 2020 as much as two-thirds of its energy will be imported. Over the same period, the UK's reserves of oil and gas in the North Sea are likely to virtually run out. In this context, it is hardly surprising that the EU's energy commissioner Andris Piebalgs last week called for a more co-ordinated European energy strategy. "It is clear that Europe needs a clearer and more collective and cohesive policy on security of energy supply, " he said.

He promised to issue draft proposals for a new European energy policy in the spring, with the aim of finalising it by the end of 2006. This summer, Piebalgs is due to visit Scotland's oil and gas fields in response to an invitation from the Scottish National Party MEP, Alyn Smith.

Along with Blair's energy review, it is possible that Piebalgs's new policy will seek to open the door for building more nuclear stations. They are seen by some as the best way of ensuring future energy security.

But this is disputed by experts who point out that reactors only produce electricity, which cannot replace the oil that fuels our cars and lorries.

Neither is nuclear power a cheap or reliable source of electricity, they argue.

"The nuclear stations we have built have been economic and technical disasters, " claimed Professor Jonathan Stern, director of gas research at the industryfunded Oxford Institute for Energy Studies. "It is a 1970s fallacy that anything you produce yourself is secure and anything you import is insecure. It's just not an empirical fact."

The dispute between Russia and Ukraine has not altered Stern's view that importing gas is likely to be a more secure option that relying on nuclear power. Russia has never defaulted on gas supplies, and it was not in its interest to do so, he said.

In any case, the UK wasn't likely to depend on Russian gas in the foreseeable future. At the moment, it is importing gas from Norway and is planning to take more from Belgium and the Netherlands. The UK is also investing over pounds-6 billion in facilities to import gas from the Middle East, Central Asia, Africa and Latin America in the future.

Environmentalists, however, argue that it is more important to control the demand for energy than to increase the sources of supply.

"If the UK is serious about gas security we'd be going crazy over using it efficiently, " said Greenpeace's chief scientific adviser, Dr Douglas Parr.

"We burn our gas wastefully in big power stations when local power stations, which use the heat as well, could slash our need for gas. With our commitment to efficient gas use so lacklustre, worrying over gas supplies is just posturing to generate support for the unpalatable nuclear option."

Using nuclear power doesn't mean that European countries escape dependence on foreign suppliers. Its fuel, uranium, has to be bought from the countries that mine it - Canada, Australia, Niger and Kazakhstan.

The European electricity market is also dominated by just 10 big power companies. The three biggest - E.ON and RWE from Germany and EDF from France - could put up the capital for a new nuclear programme in the UK.

The best way to boost Britain's energy independence, maintained Parr, is to exploit the country's potential for renewable energy like wind, wave and tidal power.

That would also help to cut the carbon pollution that is wrecking the climate.

Antony Froggatt, an independent European energy consultant, agreed that the most obvious way of increasing energy security was to reduce the amount of energy used by industrialised countries. It was "incredibly frustrating" that governments were doing so little to save energy, he said.

He added: "Energy is a finite resource. Yet we are wasting so much that there won't be enough for the 2.4 billion people who don't have adequate access to energy resources, or for future generations."

The price of energy was too low, and would inevitably rise, Froggatt argued. The dispute between Russia and Ukraine was "a wake-up call" for expanding renewable energy production and for making major improvements in energy efficiency.

Other expert observers drew comfort from how quickly the dispute was resolved. The fact that Russia turned the taps back on after just a few days gives "some hope" to Fred Dinning, who retired as environment director of Scottish Power a week ago. "It was a market that sorted itself out, " he said. "It all sounded pretty grown-up."

There was something to be said in favour of a global energy market, which was capable of ensuring high levels of stability and security of supply. Naturally, the market wasn't perfect, and could produce some wild fluctuations in prices, he pointed out. But there was nothing inherently wrong in relying on imported energy.

According to Dinning, Blair's energy review was unlikely to raise any new issues. They had all been comprehensively examined in his government's last energy policy review just three years ago.

That recommended major initiatives to save energy, to boost renewables and to improve the gas infrastructure. Nuclear power, it suggested, was "unattractive" because it was too expensive.

"We've got enough energy in the world for everyone. We've got the technology to supply six billion people, " said Dinning, a fellow of the Energy Institute, the leading professional body for the UK energy industries. "We are not short of solutions, " he added. "What we need is a public that is willing to understand the issues. Then we need to make some choices that will shape our future."

NEED TO KNOW

THE FACTS Britain is bound to become ever more dependent on oil and gas imports vulnerable to interference. It is estimated that EU nations could be forced to import 70-per cent of their energy over the next 20 to 30 years.

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http: //www. oxfor denergy. org/ Oxford Institute for Energy Studies

http: //www. euenergy. com/ Reports by energy consultant, Antony Froggatt