According to the new Global Solar Thermal Report 2021 (see below), the German solar thermal market grows by 26 percent in 2020, more than any other major solar thermal market worldwide, said Harald Drück, researcher at the Institute for Building Energetics, Thermal Technologies and Energy Storage – IGTE at the University of Stuttgart, Germany, during a speech at the IEA SHC Solar Academy in June. This success story may be largely due to the relatively high incentives offered by Germany’s highly attractive BEG. program to finance energy-efficient buildings, as well as the country’s fast-growing solar district heating submarket. But he also warned that the solar obligations being discussed in some parts of Germany would actually mandate PV and threaten the gains made by the industry. You can find a recording of the webinar here.

In his presentation, Drucker began by outlining the long-term evolution of the German solar therml market. The success story began in 2008 and was also considered by much of the peak year for global oil, thanks to the 1,500 MWth of solar thermal capacity, or about 2.1 million m2 of collector area, installed in Germany. “We all thought things would go faster after that. But the exact opposite happened. The capacity declined year by year. in 2019, it dropped to 360 MW, about a quarter of our capacity in 2008,” Drucker said. One explanation for this, he added, was that the government offered “very attractive feed-in tariffs for PV at the time. But since the German government did not make significant changes to solar thermal incentives in the decade from 2009 to 2019, it can be ruled out that these incentives were the cause of the sharp decline. From a psychological point of view, PV is favored because investors can make money from the tariffs. On the other hand, marketing strategies to promote solar thermal must focus on how the technology generates savings. “And, as usual.”

A level playing field for all renewables

However, things are changing rapidly, Drucker says. Feed-in tariffs are much less profitable than they were just a few years ago. As the overall focus shifts to on-site consumption, PV systems are becoming more and more like solar thermal installations, and investors can save but not make money with them. Combined with BEG’s attractive financing opportunities, these changes have helped solar thermal grow by 26% in 2020, resulting in about 500 MWth of new installed capacity.

The BEG offers homeowners grants that pay up to 45% of the cost of replacing oil-fired boilers with solar-assisted heating. A feature of the BEG regulations, effective as of early 2020, is that the 45% grant rate now applies to eligible costs. This includes the cost of purchasing and installing heating and solar thermal systems, new radiators and underfloor heating, chimneys and other heat distribution improvements.

What is even more reassuring is that the German market has not stopped growing. According to statistics compiled by BDH and BSW Solar, two national associations representing the heating and solar industry, the area of solar collectors sold in Germany increased by 23 percent in the first quarter of 2021 compared to the same period last year , and by 10 percent in the second.

Increasing solar district heating capacity over time. By the end of 2020, there are 41 SDH plants in operation in Germany with a total capacity of about 70 MWth, i.e. about 100,000 m2. some bars with small gray parts indicate the total installed capacity of the heat network for the industrial and service sectors. So far, only two solar farms have been included in this category: a 1,330 m2 system built for Festo in 2007 and a 477 m2 system for a hospital that went into operation in 2012.

Operational SDH capacity expected to triple

Drück also believes that large solar thermal systems will support the German success story in the coming years. He was introduced by the German institute Solites, which expects to add about 350,000 kilowatts per year to the estimate in the near future (see figure above).

Thanks to the launch of six solar central heating installations totaling 22 MW day, Germany exceeded Denmark’s capacity increase last year, seeing 5 SDH systems of 7.1 MW, a total capacity increase after the day in 2019 joined 2020 also includes the German re-largest plant, a 10.4 MW system in hanging on Ludwigsburg. Among the new plants still to be commissioned this year is a 13.1 MW day system Greifswald. When completed, it will be the largest SDH installation in the country, located before the Ludwigsburg plant. Overall, Solites estimates that Germany’s SDH capacity will triple in the next few years and grow from 70 MW th at the end of 2020 to about 190 MWth by the end of 2025.

Technology Neutral

“If the long-term development of the German solar thermal market has taught us anything, it’s that we need an environment where different renewable technologies can compete fairly for market share,” Drucker said. He called on policymakers to use technology-neutral language when drafting new regulations and warned that the solar obligations currently being discussed in several German states and cities are essentially nothing more than PV directives, as they require rooftop PV panels on new construction or buildings being overhauled.

For example, the southern German state of Baden-Württemberg recently approved regulations that will mandate the use of PV generators on the roofs of all new non-residential structures (factories, offices and other commercial buildings, warehouses, parking lots and similar buildings) from in 2022. Only thanks to the intervention of BSW Solar, these rules now include section 8a, which clearly indicates that the solar collector sector can also meet the new solar requirements. However, instead of introducing regulations allowing solar collectors to replace PV panels, the country needs a real solar obligation, requiring the installation of solar thermal or PV systems, or a combination of both. drück believes that this would be the only fair solution. “Whenever the discussion turns to a solar obligation in Germany.”