Embodied emissions, the carbon emissions generated during the manufacture of building materials, make up a significant part of a building’s overall carbon footprint. GreeNest aims to create a construction ecosystem integrating biogenic materials and renewable energy systems to drastically reduce embodied and operational emissions. The project minimizes carbon output and resource use by using recycled and locally sourced materials, focusing on fully zero-carbon construction.
GreeNest plans to cut embodied emissions by 50% compared to the current Near-Zero Energy Buildings standard and reduce lifecycle GHG emissions by 60% while also boosting construction productivity by over 30%. Techniques such as digitization, prefabrication, and circular design are central to the project's low-emission, resource-efficient approach.
GreeNest is developing a range of advanced smart envelope systems designed to enhance sustainable building practices. Among these is the SmartWall, a modular, prefabricated wall that integrates energy-efficient HVAC components and low-carbon materials, providing flexible, multi-functional applications across various climates. Its innovative design supports high indoor air quality (IAQ) and comfort with minimal energy demands.
Another system is the GreenWall, a vertical garden integrated into building facades, which not only improves energy efficiency and reduces urban heat but also supports biodiversity and improves air quality.
The EcoTechWall is crafted from circular materials, including waste wood and natural fibers, promoting lowimpact, climate-neutral construction and contributing to a healthier indoor environment. As part of the EcoTechWall, the KARZ insulation panel uses 50-60% coffee bean waste and biogenic polyurethane (PUR) for eco-friendly insulation, achieving 20- 40% lower U-values than conventional options. The project aims to increase the coffee content, increasing carbon storage by 50%.
In the realm of windows, the Heat- Harvest Window (HHW) incorporates a ventilation system with heat recovery, effectively minimizing heating and cooling requirements while enhancing indoor air quality.
The Reversible Window offers a unique solution with a 180° rotating design, allowing it to adjust to seasonal changes by altering solar gain, thus reducing energy consumption throughout the year. Together, these envelope systems are central to GreeNest's mission to create buildings that are both energy-efficient and environmentally responsible.
The project is also advancing key technologies to further reduce energy consumption, such as the Eco-BIPV/BAPV, optimized for easy plug-and-play installation, and the CASCADE system, which leverages low GWP R290 heat pumps for eco-friendly heating, cooling, and domestic hot water (DHW). NestControls will be fine-tuned to maximize comfort and energy efficiency through dynamic thermal and daylight control.
A notable element of the project is the demonstration of its innovative solutions in four real-world construction projects and two virtual building models across five European countries. These demonstration sites include a museum and knowledge center in Berlin, an info center in Italy, and a youth recreational center in Greece, each uniquely built to showcase the feasible adoption of sustainable materielas and practices. GreeNest will employ local and regional supply chains and value networks to enhance replication potential across Europe, particularly benefiting construction SMEs.
The project's replicability is further bolstered by its emphasis on digitization and modular, adaptable building design strategies, which will allow for easier scaling and customization across multiple building typologies and climatic regions.
By incorporating renewable energy systems, the project will also target primary energy consumption reductions of 30 to 40 kWh/m², potentially pushing the building standard closer to Zero Energy Buildings (ZeB) or even positive energy standards. With a focus on not only energy efficiency but also human impact and comfort, GreeNest represents a major step forward in addressing both climate change and modern lifestyle demands in the built environment.
The GreeNest project, starting in January 2024 and ending in December 2027, is coordinated by ETHNICON METSOVION POLYTECHNION (NTUA) and co-funded by the European Union under Grant Agreement No. 101138242 and the State Secretariat for Education, Research and Innovation (SERI). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or CINEA. Neither the European Union nor the granting authority can be held responsible for them.