According to the Swedish Armed Forces, the agency responsible for the country's military, the installation of wind turbines puts flight safety at risk and jeopardises the ability of the air force to undertake low-level flying. The report containing the decision, published in October, also says wind turbines interfere with radar systems, radio links and signals intelligence.
As the Swedish environmental code gives the country's army sweeping powers to approve or reject activities carried out in the vicinity of military facilities, the decision leaves the future of almost 1,000 turbines in the balance.
Tensions have been running high since June last year, when Sweden's armed forces first announced they were imposing a temporary moratorium on the construction of wind turbines within a 40-kilometre radius of military airfields.
The blanket ban was removed after the military conducted an internal review and examined the specific conditions at each airfield. But the protected zones still covered 10% of Sweden's total landmass - equivalent to an area the size of Denmark.
The Swedish Wind Energy Association responded by presenting detailed counter-arguments and pointing out that wind energy and military airfields had so far been able to co-exist in relative harmony.
"What's more, many of the protected areas have been specifically earmarked by the state as being of national importance for the production of wind energy," says Mattias Wondollek, project manager at the trade association.
Around 280 turbines already operating within the protected zones will not need to be dismantled if they have been erected in full accordance with planning and building regulations. Should the military discover any irregularities, however, action could be taken to have the turbines removed.
"They are currently in the process of appealing the building permits granted to existing turbines in these areas, which provide a quarter of all wind energy production in Sweden," says Wondollek.
Investment at risk
The military's decision risks derailing SEK 5 billion (EUR548 million) of investments in existing turbines, as well as SEK 20 billion set aside for development projects in the restricted areas, according to a survey of member companies carried out by the trade association.
"There are already plans in place for around 700 new turbines in the protected zones. These would produce 4-5TWh of electricity, so we're not talking about trivial amounts here," says Wondollek.
Wind energy accounted for 2.5TWh, representing 1.87% of Sweden's electricity supply in 2009.
Carl-Johan Edstrom, an air force pilot and divisional military chief, defends the decision to keep turbines away from aircraft. "What was of primary importance to us when deciding on the new protected zones was the ability to continue training pilots and rapid reaction units, as well as carrying out national and international missions with our flight security intact," he says.
Edstrom says he is fully aware that other countries' military authorities do not impose such strict limits on the wind industry. "We, however, proceed from the needs and requirements of the Swedish Armed Forces," he says.
Wondollek argues a government directive explicitly instructs the armed forces to help Sweden meet its wind energy goals.
"Like military defence, energy production is also in the national interest. According to the government's appropriation directions, the military should be assisting us in ensuring that Sweden meets its renewable energy goals for 2020," he says. Sweden has pledged to derive half of its electricity from renewable sources by 2020.
Groups such as the Swedish Wind Power Association and the Federation of Swedish Farmers have joined the Swedish Wind Energy Association in petitioning the government to have the new restrictions lifted. "We're going to do all we can to force a military retreat," says Wondollek.