A Europe-wide freeze this month sparked concerns over U.K. gas reserves while shedding inconclusive light on how wind can help cope with extreme low temperatures.

The U.K.’s National Grid warned that gas supplies could run out at the beginning of March as Britain succumbed to what papers called the "Beast from the East," an Arctic anticyclone combined with a winter storm that sent mercury plunging across the British Isles.

With snow bringing much of the U.K. to a standstill, the wholesale price of gas went up by 108 percent to its highest level in at least a decade. Supply fears caused the country to rein in combined-cycle gas turbine generation, forcing other technologies to step into the breach.

The most important of these was coal. For much of the eight days or so that the U.K. was snowed under, the country’s 10.6 gigawatts of coal generation was running full throttle.

Britain’s nuclear fleet, meanwhile, maintained a constant output of around 7.5 gigawatts, somewhat less than the nation’s total reactor capacity because of scheduled and unscheduled outages.

And what about wind?

For several days, according to data from Gridwatch, wind was able to supply as much electricity as coal. Later in the month, wind generation broke a new record, delivering 14.2 gigawatts to the U.K. grid and covering 34.2 percent of electricity demand, Reuters reported.

But it is also true that as gusts from winter storm Emma dropped toward the end of the early March freeze, so did wind farm production, forcing gas turbines to increase their output again.

Nonetheless, in some quarters wind power was seen as having helped the U.K. to avert a drastic gas shortage. As a second cold snap hit the country in the middle of the month, The Telegraph praised the wind industry’s performance.

“The gas market was able to weather a second sweep of freezing temperatures over the weekend in part because the ‘Beast from the East’ brought record wind power output which cut the need for gas-fired power plants,” it said.

The issue of gas reserves is particularly sensitive because the U.K. gets most of its supplies from Europe. European gas markets, in turn, are dominated by Russia, which is currently in a diplomatic standoff with the U.K. over the poisoning of an ex-Russian spy on British soil.

With cold weather conditions persisting in many parts of Britain, gas advocates have called for greater exploitation of native gas reserves, including fracking and extracting more from the North Sea.

Richard Heap, an analyst with Oxford, U.K.-based cleantech consultancy the Tamarindo Group, said the Beast from the East would likely seem rather tame to observers from countries such as Canada or Norway.

“But for the U.K., the conditions are pretty unprecedented and are prompting a debate about energy policy,” he said. “Everyone is pushing their own agenda. This will surely raise calls for more investment in shale gas, fracking and protection for coal.”

Agendas aside, what happened with Britain’s energy system during the cold snap does raise questions over how the country will cope once most of its coal and nuclear fleet has been retired.

National Grid’s most recent capacity auction saw gas emerging as the favored technology for grid reserves, which could leave the U.K. exposed if this month’s weather conditions return in the future.

Paul-Frederik Bach, an energy consultant who studies electricity systems in Denmark, Germany and Great Britain, said fears over U.K. gas supplies and rising wind generation were raised by Howard Rogers of the Oxford Institute for Energy Studies in 2011.

“The recent supply problems confirm his analyses,” said Bach.

In planning for the future, Bach indicated that policymakers should distinguish between lack of system adequacy, which could lead to reductions in electricity supply, and lack of system security, which could lead to blackouts.

System security looks to become a bigger issue for the U.K. energy system as traditional generation is shuttered. And it is not an issue that wind alone can solve.

Nevertheless, said Bach: “I would go far to maintain control of the power system during resource shortages, because the restoration after a blackout can be complicated and time-consuming.”