Renewable energy systems

Given supply risks and the strategic importance for the European economy, some raw materials, including technology metals, are classified as critical under the Critical Raw Materials Act (CRMA) or as strategic due to their relevance for environmental, digital and defence technologies. As a result, high-quality recovery of these raw materials is becoming increasingly important. The revised Buildings Energy Act (Gebäudeenergiegesetzes, GEG) includes the provision that from mid-2028 at the latest, all newly installed heating systems must operate with at least 65 percent renewable energy. In new-build areas and larger cities, this requirement will apply even earlier. As a result, heating systems such as heat pumps will increasingly replace oil and gas heating, helping to decarbonise heat supply. This will reduce demand for raw materials such as copper, steel and aluminium for fossil-based heating systems while initially increasing demand for heat pumps.

The status quo of circularity in renewable energy systems varies significantly depending on the raw materials used: for copper and, in some cases, aluminium there are well-established, high-quality recycling cycles; glass, on other hand, is often downcycled; and, at the other end of the spectrum, for materials such as indium from PV modules and fibre-reinforced composites in wind turbine rotor blades, recovery is still linear and low value – high-quality recycling has so far not progressed beyond pilot projects due to a lack of economic viability. While technical solutions have been extensively researched, they have yet to reach market maturity or commercial viability.

With a technical lifespan of around 20 to 30 years for installations such as wind turbines and PV modules, and the beginning of a significant expansion of these technologies driven, in particular, by the 2000 Renewable Energy Sources Act (Erneuerbare-Energien-Gesetz, EEG), a very sharp increase in the volume of waste is expected in the coming years, both for PV modules^[ii] and wind turbines. Infrastructure must now be established or expanded to ensure the proper take-back and environmentally sound and high-quality recovery of these installations. The existing legal frameworks differ significantly between the various technologies: PV modules fall under ElektroG and are therefore subject to product responsibility, including shared responsibility, whereas operators of wind turbines are required to set aside appropriate reserves for dismantling.

Recycling requirements for different wind turbine components fall under various general and specific regulations, including the waste hierarchy under section 6 of the Circular Economy Act (KrWG), the GewAbfV, the Waste Oil Ordinance (Altöl-Verordnung) the Battery Act (BattG) and the Secondary Construction Materials Ordinance (Ersatzbaustoffverordnung, ErsatzbaustoffVO). Heat pumps may fall under the scope of the Waste Electrical and Electronic Equipment Directive or the national ElektroG.

Manufacturers are fundamentally responsible for disposal, treatment and recovery. However, as large-scale, fixed installations (or devices) heat pumps may be exempt from ElektroG and instead their disposal is subject to Circular Economy Act (KrWG) regulations. Fluorinated greenhouse gases (F-gases), such as hydrofluorocarbons (HFCs), used as refrigerants must be recovered by system operators under the F-gas Regulation so that they can be recycled, reprocessed or destroyed. The Chemicals Climate Protection Ordinance (Chemikalien-Klimaschutzverordnung, ChemKlimaschutzV) requires manufacturers and distributors of F-gases to take them back or ensure they are taken back.

Barriers to the circularity of raw materials in renewable energy systems are complex and, as shown, vary greatly between the individual raw material groups and applications. For instance, high recycling rates are already achieved for mineral construction materials such as concrete in wind turbines, but the challenge lies in incentivising the highest possible recycling quality and preventing downcycling (see Section ‎4.8). Wind turbines pose particular challenges in relation to rotor blades, The potential for lightweight construction in this regard is an important factor in the rapid ramp-up of wind energy production. At the same time, the high-quality recycling of glass-fibre-reinforced plastics (GFRP) is generally not yet economically viable, meaning that glass fibres are, for example, often used as raw materials in cement clinker production in cement plants. Carbon fibres from carbon-fibre-reinforced plastics (CFRP) can be recovered using pyrolysis, but plant capacity must be scaled to match projected waste volumes. There is also considerable uncertainty regarding the materials used in rotor blades.^[vii] Additionally, there is generally still a lack of economic incentives for the separate collection of permanent magnets used in direct-drive wind turbines, so they are often processed together with steel scrap and and therefore not reused.

The careful dismantling, transport and proper collection of PV systems and modules are key requirements for (preparation for) reuse or high-quality recycling and recovery of raw materials such as glass or technology metals, including critical and strategic metals, like silicon, indium and gallium. In addition, there is a lack of practical requirements, criteria and application guidelines to support decisions on whether a module or end-of-life module can still be used as a functional second-hand device, can be prepared for reuse as a waste management measure, or should be recycled. Particularly with regard to the disposal of end-of-life PV modules in private use, both the general public and the trades companies contracted to dismantle them often still lack awareness of the correct way to dispose of them or incentives to return them to designated collection and take-back points. There is also often a lack of suitable infrastructure at the waste collection points run by the public waste disposal authorities. The limited quantity of end-of-life modules is also a barrier to the large-scale and economically viable implementation of recycling processes, particularly for thin-film modules. There is also evidence of illegal shipments abroad of modules that are, in fact, end-of-life modules. Moreover, product design is not yet optimised for dismantling and material separation. Multi-layer composite structures must be designed in a way that does not prevent repair, high-quality recycling and recovery of critical raw materials. Promoting safe and sustainable design, including in terms of application, is therefore of the highest priority.

Heat pumps and switchgear in PV systems and wind turbines pose particular challenges due to the use of high-climate-impact F-gases, which must be recovered under the F-gas Regulation and subsequently recycled, reprocessed or destroyed. While EU-wide regulations and obligations govern the take-back, disposal and treatment of heat pumps falling under ElektroG, there are currently no specific disposal regulations (for example take-back structures) for heat pumps that do not fall within its scope.

Renewable energy systems are being addressed in various European and national initiatives. The European WEEE Directive, which has been transposed into national law through ElektroG, establishes binding recycling targets for PV modules and heat pumps  and is currently in the consultation phase for revision. At national level, the Ordinance on the Treatment of Waste Electrical and Electronic Equipment (Elektro- und Elektronik-Altgeräte-Behandlungsverordnung, EAG-BehandV) sets out initial requirements to enhance circularity in the initial treatment and recycling of PV modules, as well as for electrical equipment and components of electronic equipment in general (for example, components of heat pumps that fall within the scope of ElektroG). The European Commission is also developing regulatory proposals for PV modules, inverters and complete PV systems.

A working group on heat pump circularity is currently being established at the International Energy Agency (IEA) to explore approaches for optimising the circularity of these installations at the international level. The industry has also taken up the issue, and in some cases has made or announced voluntary commitments towards zero waste by 2040.

Based on the vision of a comprehensive circular economy for 2045 presented in Section 1.3, and complementing the guiding principle and overarching goals formulated in Section 2, the following additional goals apply to this action area:

In the field of renewable energy systems, there are various targets that need to be balanced appropriately. Given the goal of achieving greenhouse gas neutrality by 2045, a significant increase in the expansion of renewable energy is necessary. In this context, particular emphasis should be placed on ensuring high-quality material cycles, especially for critical and strategic technology metals. This will directly contribute to resource conservation and climate action while also strengthening the resilience of supply chains in the renewable energy sector.

National and European objectives:

• Recovery of critical raw materials from wind turbines and PV modules, in line with the targets of the Critical Raw Materials Act (CRMA).
• Development of technological standards for scaling uptake-back infrastructures.
• High-quality recovery or reuse of decommissioned rotor blades by 2040.
• Development and implementation of concrete indicators for assessing the recyclability of products and their components by 2030.

Promoting circular installation design

To strengthen circularity in individual components of wind turbines that are not yet (or cannot be) recycled to a high standard, steps should be taken to promote product design that is more aligned with circular principles. To this end, at European level (and ideally internationally) in dialogue with installation manufacturers, Germany will support the development of standards for rotor blade design, such as dismantling capability and the clean separation of fibre‑containing components. This will build on DIN SPEC 4866, in which relevant concepts are already being developed in collaboration with industry. This DIN SPEC should be incorporated into international standardisation processes in the near future. The BMWK supports relevant technological developments as part of the energy research programme.

Optimising recycling

While incentives for circular product design will only apply to newly installed wind turbines, optimised dismantling and recycling processes are needed for the rapidly increasing number of decommissioned installations in the coming years.

To this end, secondary legislation will be adopted stipulating that carbon fibre-reinforced plastic (CFRP) waste may not be disposed in waste incineration plants and may not be used for energy recovery in cement kilns, or only if certain requirements are met. In parallel, the introduction of quality requirements for recycling facilities handling rotor blades and for specialist waste management companies handling fibre-containing waste is being considered. The Länder should be consulted in order to coordinate new and further measures. One of the aims of this is to ensure that regional regulations are further developed in line with the NCES. However, this must not result in such waste being consigned exclusively to landfill.

At the same time, therefore, targeted research funding is required for innovative recycling processes for glass fibre-reinforced plastic (GFRP) and CFRP waste, as well as other relevant waste streams (such as balsa wood). The BMWK provides funding for such research as part of the energy research programme.

To promote the recycling of permanent magnets, the implementation of specific measures under the Critical Raw Materials Act (CRMA) will be examined. These could include comprehensive monitoring of product flows, including imports and exports of scrap, the establishment of a collection and logistics system for permanent magnets from relevant sources, the introduction of collection and recycling targets for permanent magnets, or support for facilities for the reuse and recycling of permanent magnets.

Beyond recycling, innovative applications for reuse or repurposing of individual components will also be promoted, for example through demonstration projects. Rotor blades, for instance, could be reused as structural components in noise barriers, production halls, stages, observation towers or floating offshore platforms. This reuse approach could cut carbon emissions and costs, while giving the rotor blades a second life of 10 to 20 years, during which time innovative recycling methods could be further developed.

Extending the lifespan of photovoltaic modules and promoting circular installation design

PV modules have a long technical lifespan, but have often not reached the end of their functional life when support is discontinued and modules or entire PV systems are dismantled. The aim must therefore be to extend the service life of modules through second-life measures, in other words, the repair and reuse, or preparation for reuse, of used or end-of-life PV modules. This will lower consumption of primary raw materials and resources and reduce environmental impacts. To support this, a digital documentation guide will be developed to identify and present procedures for handling disused modules to be dismantled and to establish clear and verifiable criteria for this. In future, this will be based on data from digital product passports to be developed for PV modules. As a central element of the guide, practical checklists, verifiable criteria and instructions for action will simplify the distinction between waste and non-waste, which will also help reduce and prevent illegal (waste) treatment and shipments.

Strengthening producer responsibility will be reviewed, including the possibility that in future, the mandatory registration of a PV installation with the Bundesnetzagentur (federal network agency, BNetzA), will include a legally binding registration number. This measure should not increase administrative burden (it could be implemented in an automated manner) but will ensure that only legally compliant and safe modules are put into operation and that manufacturers do not evade their organisational and financial responsibility for end-of-life disposal.

The NCES will also create incentives for circular product design. Current PV modules are highly complex, optimised for electricity generation and minimising efficiency losses, but this complexity often significantly hinders recycling. Individual material fractions and components must be designed to be as easy to dismantle and repair as possible, without compromising durability, performance or economic viability of the modules. Germany will work to promote this type of design for circularity at European level.

Optimising disposal

The disposal chain for installed PV modules and existing PV systems, more and more of which will reach the end of their service life in the coming years, will be strengthened, from collection and take-back to initial and further treatment and the recovery of raw materials. To this end, when a PV system is decommissioned, BNetzA will in future automatically send households guidance on the proper and environmentally sound disposal of end-of-life PV modules. Operators of large-scale PV systems and solar parks will also receive guidance on correct disposal procedures. In addition, it will be examined whether specific documentation requirements for the proper disposal of large volumes of waste are necessary, without increasing administrative burden (for instance, through digital and automated processes).

As part of the upcoming revision of the WEEE Directive, consideration will be given to how the requirements for high-quality recycling of PV modules can be further developed. One potential option is the introduction of material-specific recycling targets, which should also align with the objectives of longevity, repairability and reusability of PV modules, as well as uniform EU treatment standards.

Special investment programmes will be promoted to develop and expand recycling capacity (see Section ‎3.5), particularly for CIGS (copper indium gallium selenide) thin-film modules and crystalline silicon modules.

 Further research projects addressing the recovery of silicon, indium and gallium from PV modules will be supported in order to make relevant economic processes market-ready. The development of high-quality recycling processes will be supported for new PV technologies such as building-integrated modules, perovskite solar cells or PV films or modules.

To support the proper disposal of PV modules that are no longer in use, the opportunities and risks of different models will be examined. Additionally, guidance on disposal will be developed and more widely communicated to skilled trades companies and associations, as well as end users.

The potential for resource efficiency in heat pumps varies significantly. A distinction must be made between small household systems and large heat pumps used in industry and district heating networks. Small household systems exist in greater numbers and represent a larger market. The following measures focus on small heat pumps.

Promoting circular installation design

Heat pumps are already generally recovered separately due to the value of their materials. However, given the scaling needed for the energy transition, incentives should also be introduced for circular design, focusing on system upgradeability and the repairability of individual components. This is also crucial for enabling consumers to use their heat pumps for as long as possible. Germany will work at European level to support this.

At the same time, targeted support will be provided to research projects that build on findings such as those from IEA SHC Task 71 on life cycle assessments of heat pumps and IEA (Heat Pumping Technologies) HPT on circular economy approaches. 

Supporting circular business models

The transition to circularity in heat pumps will depend on supporting appropriate business models that ensure the most efficient use and high-quality circularity of systems (for instance, in the context of Heating as a Service).

Potential regulatory barriers, such as those affecting contracting models compared with traditional distribution structures, will be examined and addressed, particularly with regard to necessary take-back systems (reverse logistics).

To further support the scaling of heat pumps, a monitoring system will be established to determine whether adjustments to product responsibility are needed.

Developing an optimised disposal system

In practice, heat pumps are often not disposed of in accordance with the requirements of ElektroG. This is often due to a lack of awareness, market structures or to the fact that (large) heat pumps (and fixed installations) may fall outside the scope of ElektroG, meaning disposal follows a different route (which may not always be appropriate or environmentally sound). To ensure proper disposal of heat pumps, guidance will be developed and more widely communicated to skilled trades businesses and associations, as well as end users. Additionally, it will be examined whether mandatory take-back schemes could help improve circularity for products, individual components or raw materials.