1. Skip to content
  2. Skip to main menu
  3. Skip to more DW sites

Energy Farmer

Kate HairsineNovember 16, 2006

As German farmers face an uncertain future, some are turning to alternative crops to keep their land. Meet an innovative farmer who has turned his farm into a million dollar renewable power station.

https://p.dw.com/p/9Ojq
Heiner Gärtner proudly shows off his solar panelsImage: DW

When Heiner Gärtner inherited his father’s farm in Bavaria in 2002, it was indistinguishable from the neighboring land. The 75 hectares of rolling fields rippled with wheat, corn and sugar beet, and some 800 pigs filled the stalls beside the homestead.

Four years later, the farm near the small village of Buttenwiesen looks somewhat different from those surrounding it. The pigs and fields of corn are still there, but now 10,000 glinting solar panels take up a tenth of the farmland.

Solaranlage in Buttenwiesen in Bayern
When it was built, Gärtner's thin-film solar park was the biggest in the worldImage: DW

There are also two enormous new tanks on the rise behind the homestead. They house a biogas plant fed with the corn and pig manure.

Thirty-five year old Gärtner has just come in from the fields, and he looks every inch a farmer. He’s wearing mud-smeared Wellington boots, a battered leather hat, and sweatshirt advertising "Swabian suckling pigs."

Harvesting energy not that different

Even though he primarily harvests energy, Gärtner still sees himself as a farmer. "It wasn’t such a big change," he said, because traditional farmers also collect the energy from the sun on their fields.

"The various plants transform that solar energy into food. Now, we just have found a new way of refining the sun’s energy, in that sense, it isn’t so different from agriculture."

But how did this all come about? After finishing his studies in Agricultural Engineering, Gärtner spent six months in northern Germany. He and his ex-classmate Ove Petersen spent many nights talking about how they could make their farms more profitable. They just didn’t see a future in traditional farming.

Inspired by wind farms

Gärtner and Petersen were "fascinated" by the number of wind turbines dotting the countryside in the north of Germany. Many of these small-scale wind farms were initiated by groups of farmers, rather than large companies.

Wind power generators, Schleswig-Holstein, Germany, photo
Gärtner was inspired by wind turbines like these in northern GermanyImage: AP

But Bavaria, with its inland location, lacks the coastal winds that keep the windmills turning in the north. So Gärtner and Petersen "took a look at other possibilities."

"Photovoltaic looked good at that time, that was in 2003 -- and we found out that Bavaria had very good solar values," he explained.

Bavaria is one of the regions in Germany with the most sunshine in the country. According to the country’s national meteorological service, the southern part of Bavaria has an annual average of 1000 to 1200 kW hour of solar radiation per square meter.

Luck with a sunny location

Gärtner’s farm - just over 100km northwest of Munich - has an especially sunny location, with few hills to block the light. These positives prompted Petersen and Gärtner to investigate turning some of the fields into rows of photovoltaic panels.

But first, they set up a solar laboratory on the barn roof to test different solar panels under the same conditions. Gärtner and Petersen, who went into partnership for the project, then built the solar park of 10,000 modules in Gärtner’s field. The rows of solar panels are spread over seven hectares, and at the time, it was the biggest thin-film solar park in the world.

Buttenwiesen in Bayern
These fields in Bavaria recieve some of the most sun in GermanyImage: DW

Germany is the leading producer of solar power worldwide. Despite this, it was still extremely difficult for Gärtner and Petersen to find financers for the 4.1 million euro construction costs.

"It was a huge deal because the banks didn’t really have a concept of what we wanted to do", he said. That was in 2004 and there were only a few solar parks in existence, and these were built by large corporations.

"The general public didn’t know what a solar park actually was, or if it could be profitable, or understand how you could manage to pay back the loan," Gärtner said.

The two men benefited from a German renewable energy law that guarantees a minimum price for each kilowatt of energy for the next twenty years. Without this security, Gärtner said, the project wouldn’t have been possible.

The solar park has now been operating for two full years. According to Gärtner, it’s running better than expected, and within the next eight years he expects to pay off his loans -- for the solar park that is.

Pig manure fed into biogas plant

Because Gärtner hasn’t just stopped at reaping the sun’s energy, he is also using the corn on his fields and the manure from his pigs to feed the biogas plant he’s built for 1.4 million euros behind his house.

Schweine
The pig manure is important in regulating the biogas outputImage: AP

The mix is then fed up to a large fermentation tank where bacteria break down the vegetable matter, creating methane and carbon dioxide. Waste organic matter from the process is then ploughed back into the fields as fertilizer.

Unlike the solar park, which basically looks after itself, the biogas plant requires constant supervision. Gärtner has to ensure the plant receives a constant mix of vegetable matter in order to have constant gas production.

"There are billions of bacteria involved, and they have to be fed, exactly like you have to feed other animals like pigs or cows," he said.

Although the biogas plant is more work, it has several advantages. It runs night and day, whereas the solar plant only produces energy during the daytime. And while Gärtner can’t control the amount of sunshine, he can influence the amount of gas he produces by feeding the plant correctly.

The biogas plant has been up and running since July this year. Gärtner hopes to get around 2.7 to 2.8 million kW hours from the biogas, that’s more than double the capacity of the solar park.

With a guaranteed price under the German renewable energy law of 16 cents per Watt-hour, if everything goes fantastically, Gärtner will have paid off the plant within seven years. That’s if the motor converting the gas into electricity runs for every one of the 8,760 hours there are in a year.

Difficult getting planning permission

Although many of the house roofs around Buttenwiesen are plastered with solar panels, Gärtner is the only one with a solar park in his fields. This is because -- in a seeming contradiction -- Germany has such strict environmental controls that it is extremely difficult to get permission to convert a field into an industrial site. It is estimated that in Bavaria, only one solar park project from 25 receives a planning permit.

Maisfeld, Biobauer, Landwirtschaft
Gärtner uses corn from his fields to feed the biogas plantImage: AP

It took eight long months for the Buttenwiesen local council to authorize Gärtner’s solar park --- and this was with the full support of the mayor, Norbert Beutmüller. The mayor is convinced that alternative energy is the only way to have a viable future, and is disparaging about politicians that block renewable projects.

"We politicians have to say 'yes' to alternative energy," he said. "Many politicians just live from election period to election period, but they also have to consider the future, and if necessary make unpopular decisions."

According to the German Renewable Energy Foundation, renewable energies will account for 11 percent of Germany’s energy use in 2006.

That means Germany produces more energy from environmentally friendly sources than the entire energy used in states such as Denmark or Ireland.

The farmer Heiner Gärtner and the council of Buttenwiesen are a prime example of what can be done when individual initiative is supported by political will. And as the effects of climate change become more evident, we can only hope that more people play their part in combating climate change.