LONDON -- Renewables, more energy efficiency and greater electrification will be the backbone of any future low-carbon E.U. energy mix, although natural gas will also pay a pivotal transitional role as the bloc strives to meet its goal of slashing emissions by up to 95 percent from 1990 levels by midcentury, the European Commission said yesterday.

According to a range of five possible energy decarbonization scenarios presented in its so-called 2050 Energy Roadmap, the commission calculates than none will cost more and some may cost less than continuing business as usual.

"It is more or less the same if we go for business as usual or for more ambitious scenarios which involve a lot of renewables," E.U. Energy Commissioner Guenther Oettinger said at a news conference presenting the plans.

Gas storage tanks in north central Pennsylvania. Will the gas be exported to Europe? Photo courtesy of Flickr.

And there is no time for prevarication. Current policies will only achieve less than half the 27-nation bloc's decarbonization goal, and decisions being taken already on energy sources and infrastructure risk locking in a high-carbon future, the commission said. Not only that, but acting now will be far cheaper than waiting, it added.

"Decisions being taken today are already shaping the energy system of 2050. To make the necessary transformation of the energy system in time, the EU needs much greater political ambition and a greater sense or urgency," it asserted.

The five scenarios set out in the plan range from a central focus on energy efficiency to concentrating on capturing and storing carbon from coal- and gas-fired power plants and making an all-out push for renewables.

To the consternation of some green groups, nuclear power is given a role -- albeit of varying importance -- in all five scenarios, although the commission insisted that it is agnostic on whether any of the European Union's member states should go down or stay on the nuclear path.

But the common theme of all is far more renewable energy, more electrification and lower energy consumption through greater efficiency.

Renewable energy grows from 10% to 55%

"The share of renewable energy (RES) rises substantially in all scenarios, achieving at least 55 percent in gross final energy consumption in 2050, up 45 percentage points from today's level at around 10 percent," the commission said.

Electricity must also double its share in final energy demand in the European Union to around 39 percent by 2050, the commission said, possibly providing up to 65 percent of energy demand by passenger cars and light-duty vehicles.

The power grid will also have to undergo a major structural change, decarbonizing by up to 65 percent by 2030 and 99 percent by midcentury, the commission said. "The analysis also shows that cumulative grid investment alone costs 1.5-2.2 trillion euros between 2011 and 2050, with the higher range reflecting greater investment in support of renewable energy," it said.

In his news conference, Oettinger insisted that coal-fired plants without commercially viable carbon capture and storage would not be acceptable and that gas -- with half the carbon emissions of coal -- would be a crucial transitional power source. But it, too, would eventually have to have CCS technology applied.

The commission document said increased gas use could help cut carbon emissions using existing technologies up to 2035.

On the downside, electricity prices will also rise under most scenarios, with the pain enduring for two decades before prices start to fall again, the commission said.

An essential accompaniment to decarbonization generally will be major energy savings through greater efficiency, with primary energy demand dropping by between 16 and 20 percent by 2030 and 32 to 41 percent by 2050.

Under all the scenarios, the bloc's emissions of greenhouse gases fall sharply while at the same time reliance on imported fossil fuels declines sharply, adding to energy security, the commission said.

Imported fossil fuels drop eventually

"In all decarbonization scenarios, the EU bill for fossil fuel imports in 2050 would be substantially lower than today," the document said.

But, to placate those who are against the European Union's taking unilateral action to curb carbon emissions in the absence of similar moves by other countries, the commission stressed that putting any of the scenarios into practice will require a close eye on the international stage.

"A potential trade-off between climate change policies and competitiveness continues to be a risk for some sectors especially in a perspective of full decarbonization if Europe was to act alone. Europe cannot alone achieve global decarbonization," the commission said. "Safeguards against carbon leakage will have to be kept under close review in relation to efforts by third countries."

It also stressed the vital need to keep the general public informed and involved, as the move to a low-carbon economy would affect employment and power costs and have implications for education and training as well as have a deep social impact as more power stations, more renewables and a more extensive grid were built.

"Citizens need to be informed and engaged in the decision-making process, while technological choices need to take account of the local environment," the commission said, putting particular emphasis on the need to support lower-income consumers facing inevitably higher fuel bills.