German forests are dying in part due to drier and hotter summers, and heat-loving bark beetle plagues that have destroyed ubiquitous spruce trees. More trees died in Germany in 2020 than in any other previous year, including beech trees planted widely in the past decade for their climate resilience. This week's national forest summit titled "Waldsterben 2.0" (Forest Dieback) asks what can be done.

While the climate crisis and rampant bark beetles are a major cause for concern, the forest summit aims to rethink and realign the way forests are managed. One example is the widespread planting of fast-growing spruce conifer trees after World War II in areas where they are not native. Making up 25% of German forests today, spruce is an Alpine tree that requires wet and cold conditions.

"It is the artificial forest that is dying," said German forester and author, Peter Wohlleben. "It's not a natural forest, it's not a primeval forest," he told DW. "In the next 10 years or so, we could see 50% or more of the forest dying because of bad management." Spruce forests only retain around 5% of rainwater due to soil compacting during harvesting. Dry summers compound their plight.

"To fight climate change, it would be best to leave the forests alone," said Wohlleben, the author of the bestseller "The Hidden Life of Trees." "Ecosystems when left on their own are much more resilient." He said monoculture forests must once again be populated by diverse native species. Wohlleben is the founder of the Forest Academy in western Germany, which is hosting the crunch forest summit.

Trees are community-minded — they learn from each other, especially in times of drought, said Wohlleben. When one tree recognizes that water is running out, they then pass on the information to other trees and collectively reduce water consumption. "The more we disturb this social network, the weaker the forest gets," the author told DW.

"Biodiversity protection must be the basis for whatever we do," said Judith Reise, a researcher at Germany's Öko-Institut, about the strategies driving this week's forest summit. Diverse and climate-resilient forest ecosystems need time, becoming carbon neutral after 400 years, she said. But so far only 2.8% of German forests are protected for biodiversity, well short of a 2020 target of 5%.

The oldest existing stand of undisturbed forest on the German island of Vilm is only around 300 years old, explained Reise. "We don't have wilderness in Germany," she said. Forests have been overmanaged for timber extraction, but also due to a cultural belief that forests are also for recreation, and that unsightly dead and fallen wood — that is essential to biodiversity — must be cleared.

But the forest summit on August 5 and 6 will also consider the need to promote the sustainable harvesting of timber to fight climate change, especially by replacing high carbon-emitting building materials such as steel and concrete. "This could be a very powerful solution," said Christopher Reyer, a researcher at the Potsdam Institute for Climate Impact Research and forest summit participant.

Wind power has been used for centuries. It pumps water, grinds grain, saws wood and brings sailing ships to their destination. In Europe, there were hundreds of thousands of wind turbines in the 19th century. The Dutch mainly used them to drain marshes. Today, wind power generates clean electricity and is central to meeting climate targets.

Wind turbines often generate the cheapest energy. Electricity from a new coal or nuclear power plant costs two to three times more today. Wind power generated on land is particularly cheap. According to forecasts, the cost of wind power will drop even further, to €0.03 ($0.04) per kilowatt hour (kWh) by 2030 in good wind locations.

A large wind turbine installed near Wilhelmshaven in northern Germany generates 6,000 kilowatts of power and covers the household electricity needs of 10,000 people there. Older models dating back 25 years, only achieved 500 kilowatts — enough for about 500 people. Modern turbines now stretch up to 180 meters into the sky. The taller they are, the more wind they catch.

At sea, the wind is reliable and strong. About 5% of the world's wind power comes from offshore parks like this one off the Dutch coast. Turbines such as these have an output of up to 10,000 kilowatts. From 2025 their capacity is expected to rise to as much as 15,000 kilowatts and provide electricity for more than 40,000 people.

Half of all new wind turbines worldwide are currently installed in China. In 2020 alone, the country built new turbines with a capacity of 52 gigawatts of wind power. That is equivalent to the output of 50 nuclear power plants. The pioneers in wind expansion are Denmark and Germany. Denmark already covers about 50% of its electricity needs with wind power, while Germany achieves 25%. 

About 1.3 million people work in the wind industry worldwide. About 550,000 of them are in China, 110,000 in the USA, 90,000 in Germany, 45,000 in India and 40,000 in Brazil. Installing and operating wind turbines is more costly than coal-fired power, so the expansion of wind power is creating more and more jobs. 

In densely populated regions, wind power is often met with resistance. But this can change when citizens get involved in local projects. In Starkenburg, near the German city of Frankfurt, for example, many residents favor an expansion of wind power. They are investing in new turbines — and profit from the sale of electricity.

In the past, sailing ships carried freight all over the world, but then diesel engines took over. Now, modern sails are coming back into play. With additional wind propulsion, the energy consumption of freighters can be reduced by up to 30%. In addition, ships will be able to use green hydrogen as fuel in the future.

There is enough space in the sea for wind power. But in many places the water is too deep for a foundation in the seabed. Floating turbines on buoys are an alternative. They are fixed to the seabed with long chains. Floating wind farms already exist in Europe and Japan, and remain stable even during storms.

The 147-meter-high Strata SE1 skyscraper in London is an eye-catcher with futuristic wind turbines. But such rooftop installations are usually not economical, because the wind in cities is generally too weak. Photovoltaic systems on roofs are almost always the more efficient alternative. 

Within 3 to 11 months, wind turbines generate the energy required to build them. No CO2 is produced in the electricity generation process but they do alter the landscape. Still, compared to other energy sources, they come off best in the environmental balance sheet. According to Germany's Federal Environment Agency, their environmental cost is 70 times lower than that of coal-fired power. 

Wind and solar power plants together can meet the world's energy needs. Wind turbines generate electricity at wind speeds of 10 km/h and above. In regions with a lot of sun, photovoltaics is the cheapest energy source. A little further north and south of the equator, it is usually a mix of wind and solar power. In particularly windy areas, wind power can become the most important source of energy.