Energy and emissions analysis of Next Generation Electrochromic Devices

The impact of buildings on the environment, energy consumption and climate change is significant, as they use a large amount of resources across their life-cycle. Since windows play an important role in the overall energy and environmental performance of buildings, emerging technologies are focused on the optimization of these building components. Among window design technologies, electrochromic (EC) devices have received growing interest for their ability to dynamically manage the daylight and solar energy entering buildings. Near-infrared switching electrochromic (NEC) glazed windows use a novel EC window technology that is able to continuously provide high transparency while modulating solar heat gains. This study evaluated the manufacturing phase of NEC windows to understand if their use phase performance comes at acceptable manufacturing burdens. This study also identified which constraints are connected to the market shift to the novel technology, which can provide the research community with useful information to better design the technology as it develops. A comparative “cradle-to-gate” Life Cycle Assessment was carried out between NEC and conventional EC windows. The obtained results for the Global Warming Potential of the conventional EC device was 85 kg CO2-eq/m2 and the Cumulative Energy Demand was 1680 MJ-eq/m2. Results for the NEC device were found to be 50 kg CO2-eq/m2 and 1050 MJ-eq/m2, with the reduction primarily due to replacing the energy intensive thin film deposition used in conventional EC with a solutionbased coating process. Finally, when an entire window is modeled (EC device, frame, glazing and sealing), the difference over conventional EC, in terms of primary energy consumption, ranged for the whole window manufacturing from 15 to 21%, depending on the material of the frame.

JRC.D.3 - Land Resources