Germany has long been one of the world’s leading centers of the wind industry. Thus I welcomed an opportunity to question Esther Frey, renewable energies expert at Germany Trade & Invest (GTAI), about this technology’s effectiveness and future development. GTAI is the foreign trade and inward investment promotion agency of the Federal Republic of Germany. Ms Frey provided some valuable insight into some of the issues involved in developing Germany’s Wind Energy Potential.

In addition to Climate Change, Western Europe’s drive to adapt renewable technologies arises from the scarcity of fossil fuels.

Germany  possesses enough lignite coal, but is dependent on imported gas and oil. This makes it vulnerable to external forces and unexpected price rises.

Renewable energy sources offer a way to  reduce dependence on imports and thereby improve energy supply security.

Ms Frey pointed out that “Germany started to develop renewable energy technologies such as wind and solar early on” and hopes to obtain at least 80% of its energy from renewable sources “by no later than 2050.”

“Of course, climate change is a major factor in Germany’s move towards renewable energies,” she said. “This is enshrined in the federal government’s energy plan (Energiekonzept 2050) and the Renewable Energy Sources Act (EEG) 2012. The purpose of the act is:

“to facilitate a sustainable development of energy supply, particularly for the sake of protecting our climate and the environment, to reduce the costs of energy supply to the national economy, also by incorporating external long-term effects, to conserve fossil fuels and to promote the further development of technologies for the generation of electricity from renewable energy sources.”

Everyone knows that the wind does not blow 100% of the time. US wind farms, for example, are said to produce an average of about 32% of their nameplate capacity.

In Europe they use the term “full load hours.”  This figure is of limited value without knowing the break even point and that is where things get complicated. There are other factors to be considered:  geographical conditions, wind speeds, the cost of the project and the types of turbine that are used (characteristic curve etc).

I was never-the-less impressed by the fact Germany’s off-shore wind projects achieve about 51.4% of their equivalent full load.  The estimates for onshore facilities are lower, the best performing areas achieved a high of 38% and the average is 27.9%.

Schleswig-Holstein is expected to achieve 100% of its electricity from renewables in 2014.

“However, the majority of this power comes from wind and the state feeds huge amounts of electricity into the German grid on windy days,” Ms Frey said. “This electricity is then also consumed in the rest of Germany. When there is less wind, the state imports energy from the German grid.”

Schleswig-Holstein hopes to be producing three to four times more electricity than it requires by 2020.

As the wind is not constant, this technology requires a back-up. In another article, George Taylor of Palmetto Energy Research told me this is generally a fossil fuel producing plant (coal, or gas) and this can get expensive if they are run at less than 40-50% capacity.

“The flexibility of fossil fuel power plants depends on the technology and fossil fuel used,” Ms Frey wrote. “Generally speaking, gas power plants are more flexible than coal power plants. This affects their ability to produce so-called balancing power during peaks in electricity demand. It is more efficient to run fossil fuel power plants at full capacity.”

“As the share of renewable energies increases in Germany from around 25% today to 80% in 2050, it will be a major challenge to integrate fluctuating renewable energies such as wind and solar into the energy infrastructure while ensuring that demand is always met by supply.”

Around 25.4% of Germany’s electricity came from renewable energy sources in 2013 and 35% of this came from wind energy. Thus wind energy only supplied 8.9% of the nation’s electricity demand.

In order to harvest the desired amount of renewable energy, Germany needs to

1. upgrade the transmission grid so that it is able to transmit electricity from wind and solar efficiently from areas with overproduction to areas with a lack of supply.
2. develop technologies that capture and store excess electricity  until it is needed.

“The first storage devices are already in operation and several projects are planned for the near future,” Ms Frey wrote. “The projects are being supported by EUR 200 million of German government funding.”

Some examples:

• Vanadium redox flow battery pilot project in Schleswig-Holstein planned for summer 2014 with a capacity of 1 MWh – enough, in theory, to supply 100 homes for one day. It will be built to optimize the grid integration of the Braderup-Tinningstedt wind farm.
• A lithium-ion battery to store 5 MWh in Feldheim: planned to start operation this year.
• A project by Younicos in Schwerin: coming online in September this year, the 5 MWh battery will help stabilize grid frequency in the region.
• Power to gas projects (electrolysis): RH2-WKA pilot project in Altenbrak – running since September 2013; E.ON pilot project in Falkenhagen: the system output is two megawatts – equivalent to 360 m3 of hydrogen per hour. 

Germany is investing large sums of money into developing its grid infrastructure and storage systems:

• investments in the transmission grid will amount to EUR 21-26 bn over the next 10 years (NEP 2014, initial draft).
• Dena estimates that investments of between EUR 27.5 and 42.5 bn will be needed, for the period 2012-2030, for the integration of grid technologies  (Dena Verteilnetzstudie).
• EUR 17-23 bn are planned for offshore grid connections until 2024 (already partly completed) (O-NEP 2014, first draft)

“In terms of the storage capacity that is required, it is important to note that Germany is integrated with the European market,” Ms Frey said. “The grid that already connects European countries is being developed further. This enables renewable energy to be distributed around Europe and delivered to regions where demand is high. The integration with the European grid and the investments in the transmission and distribution grid in Germany mean that a 100% storage system will not be necessary.”

As a result of their switch to renewable technologies, Germany  saved the equivalent of 148 million metric tonnes of CO2 in 2013 (electricity: 108 m tonnes, heat: 35 m tonnes, biofuels: 5 m tonnes – link).

Despite this, the nation’s emissions have grown during the past two years. Ms Frey that while the retirement of nuclear power stations will play a role, no power stations were retired during this period. She pointed to a 34 TWh increase in energy exports as a more likely candidate.

(Image at top of page: goodmorning windraeder – Photo by Dirk Ingo Franke, CC by SA 2.0)