Dear Colleagues,

Major environmental shifts such as climate change can be attributed to human activities. In socio-economic terms, the generation and consumption of required materials—energy, water, and land—produce emissions and waste, which are released back to the natural environment, causing a plethora of sequential implications.

As sustainable alternatives to conventional energy sources, a variety of renewable energy technologies and systems (RETS) have emerged, providing apparent advantages mainly during their operation, like reduced greenhouse gas emissions and waste products.

However, long-term environmental impacts, whether adverse or beneficial, should be studied in more depth, considering discrete time horizons and taking into account recent technological advances like the smart grid, the digitalization of the energy sector, higher recycling rates, and individual manufacturing and decommissioning processes.

In view of the above considerations, up-to-date cradle to cradle assessments are needed that allow the comparison of environmental impacts between different RETS from creation to disposal throughout the entire life span of materials. Inquiries which highlight the current strengths and weaknesses of the economies (industry, infrastructure, policy framework) dealing with the cradle-to-cradle of RETS are in demand. The formulation of public policies which ensure truly circular lifecycles is also vitally important for the creation of growth and job opportunities.

The proposed Special Issue will try to unify a series of research papers that discuss the various aspects of RETS concerning the use of circular economy principles in examining the sustainability of RETS, and register the currently available and developing techniques in the manufacturing and recycling of RETS.

More specifically, potential topics include, but are not limited to:

1. The currently available and developing techniques in the manufacturing and recycling of RETS.
2. The current environmental impact of RETS across the whole life cycle and cradle-to-cradle thinking.
3. The current strengths and weaknesses of the EU economy (industry, infrastructure, policy framework) for dealing with the lifecycle of RETS.
4. Public policies to ensure truly circular lifecycles of RETS, and opportunities for growth and jobs in the EU.

Dr. Costas Elmasides
Dr. Ioannis Nikolaou
Guest Editors

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• renewable energy technologies and systems
• life cycle assessment
• environmental impact of RETS
• circular economy
• cradle-to-cradle thinking
• reuse, recycle, remanufacture, and reduce