Germany's federal states have radically different approaches to developing wind and other renewables. The pro-wind regime in the coastal northern German state of Schleswig-Holstein contrasts with the anti-wind political regime in Bavaria, in the south of the country.

Similar differences are found between EU member states.

Accommodating such contrasting positions into greater European cooperation and cost saving is not an easy task. The routes chosen increasingly embed renewables into an overall approach, reflecting their expected growing role in the European electricity sector as a whole.

Germany had previously been criticised for its inward-looking approach in driving forward its Energiewende — the transition to increasing dependence on renewables in energy supply — while ignoring the impact on neighbouring countries. But, on 8 June, it was Germany that fronted the launch by 12 countries of a new European electricity sector initiative, an effort by the German goverment to rectify the situation.

Germany's insular approach is coming to an end, German economy minister Sigmar Gabriel said when announcing the "new era in energy policy". In the coming years this will be seen as a milestone in European energy policy, he said. "Security of energy supply should no longer be considered in national terms but rather in a European perspective. The neighbouring countries set clear priorities and an important signal that they can rely on each other for supply security — despite their, in part, very different national energy policies," he said.

Individual countries would no longer have to rely solely on their own resources to cover peak demand needs but rather pledge to mutually provide backup for each other, Gabriel said.

Market integration of renewables will be fostered in a coordinated way, also making use of different flexibility options, said the document, signed by government representatives from Belgium, the Netherlands, Luxembourg, France, Germany, Austria, Switzerland, Norway, Sweden, Denmark, Poland and the Czech Republic.

Federal discord

In the light of the German government's efforts, initiatives by some federal states now look counterproductive.

The windy northern state of Schleswig-Holstein and the city-state of Hamburg have launched a project, named NEW 4.0, for 100% of the region's electricity supply to come from renewables from 2035. On the surface this looks more like an independent "island" solution than a European integration project, and thus at odds with the German federal government's aims.

The New 4.0 aim is to synchronise the 15-20GW of renewables potential in northern Germany using modern energy and information technologies and the required adjustments and developments in market rules so that generation and consumption can be dovetailed with each other. The consumption side will be made more flexible with power to heat production (for district heating or industrial processes), power to energy-intensive manufacturing such as steel, and power to gas for storage concepts.

This is not an "island" project, argues Frank Burkert of consultants Ernst & Young, responsible for steering the project. The 100% renewables target will take into account electricity trading with other EU member states via existing and new transmission interconnectors, he explained.

Ideally, renewable electricity generated in the Schleswig-Holstein/Hamburg region but not needed will lead to an overall export surplus from the region, he said.

"This is not a paper project — it is to be a real, large-scale demonstration, putting into practice smart grid, storage and other technologies so far developed in research and development projects," he continued. The federal economy ministry anticipates that the know-how can then be transferred to other regions in Europe, he added.

"The aim is to show that a region with a population of 4.5 million can securely and reliably be supplied 100% with renewable energies," the two state economy ministries said in June.

The Schleswig-Holstein/Hamburg region currently has 40% renewables contribution to the electricity supply, most of it from wind energy. NEW 4.0 would see this share rise to 70% by 2025 and 100% by 2035.

In pressing ahead with its 100% target, Schleswig-Holstein/Hamburg could win a larger share of the national renewables target of 40-45% of gross electricity consumption to 2025 and 55-60% to 2035 than would otherwise have been the case.

Burkert said NEW 4.0 is competing for around €50 million in funds towards the total project concept-stage €130 million investment from the federal economy ministry's intelligent energy showcase support programme for wind. The final funding decision will be taken by the federal government before the end of 2015, with project execution scheduled for 2016-2020.

In contrast, Bavaria's "insular" energy outlook is slanted against wind energy and electricity imports. The southern state is in favour of fossil fuels and, critics believe, is in effect pushing for delayed closure of its nuclear plants, despite the federal law on nuclear phase-out to 2022.

A new Bavarian state law, which came into effect in November 2014, increased the required distance between turbines and dwellings to ten times the rotor diameter - 2 kilometres for the turbines with long rotor blades needed in the inland state, which dramatically reduced the number of potential sites for wind-energy use.

A three-month energy dialogue then ended in February with Ilse Aigner, Bavaria's energy minister, calling for negotiations at federal level to make new gas power stations in Bavaria competitive. Aigner also insisted there should be no price increases for Bavaria's people or for industry.

She pleaded for "no new transmission lines for transit of surplus electricity". New lines should only be built if needed for supply and not to take exports from elsewhere, Aigner said, prompting a warning from German energy and water federation BDEW against a Bavarian "island" solution for its electricity sector.

Cellular approach

A kind of "island" approach is implicitly supported by Germany's electro-technical federation, VDE. It proposes a "cellular approach" - creating energy cells containing households and industry at local level, connected with each other via transmission networks and sophisticated communication systems. Each cell would have its own electricity generation and storage, with grid connections to other cells, as well as consumer-side and network load controls.

"In a grass roots approach, the better electricity supply and demand can be balanced locally in the energy cells, the smaller the need for expansion of the networks," the VDE said in June.

The need for such local "island" efforts seems clear in view of the limits of cross-border cooperation, at least in the medium term. European energy regulators are discussing a cap on German electricity export capacity to Austria from 2018/2019.

The export cap proposal is discussed in a recent report by German federal energy regulator Bundesnetzagentur on the needs of Germany's last-resort emergency reserve power station up to the winter of 2018/2019. The knock-on effect could negatively impact the German wind-energy sector's market chances in high-wind periods, pointing to an increasing need to use local outlets for electricity.