SolarWind Technology Inc. has been awarded a grant from the Department of Energy (DOE) to help further develop its solar window product and bring it to market.
The Cooperative Research and Development Agreement has been awarded by the DOE’s Office of Energy Efficiency and Renewable Energy Advanced Manufacturing Office.
The award is given by the DOE’s Roll-to-Roll Advanced Materials Manufacturing Consortium. This group is led by the Oak Ridge National Laboratory, partnered with Argonne National Laboratory, Lawrence Berkeley National Laboratory, and the National Renewable Energy Laboratory (NREL).
The federal group aims to develop roll to roll manufacturing techniques. The grant is aimed toward companies who manufacture devices or systems in specialized commercial areas, or who will be able to manufacture their products as a direct result of the grant.
SolarWindow Technologies does not appear to publish the product’s efficiency. However, it has a rough and slightly confusing ‘power model‘ on its website. The power model compares how much electricity could be generated by the facade of a 50 story building – versus the rooftop of said building.
Efficiency levels of solar glass, versus standard solar modules, are far lower. Glass products have a 3-11% efficiency range versus 15-24% for commercially available crystalline silicon and cadmium telluride thin film solar modules. However, that does not mean that they do not have significant potential. Recent analysis suggests that a 5% efficient solar window, applied broadly across the United States, could generate 40% of the nation’s electricity. Last year, NREL showed off a ‘smart solar window’ that hit almost 11% efficiency in lab conditions.
SolarWindow says its product has a one year payback, and that a 50-story building facade – 360° covered – would be equivalent to approximately 10-12 acres (1-2 MW) of ground mounted solar power. Early in March 2018, the company announced an increase in its glass’ performance by 34% over prior versions.
Competitor Onyx Solar also suggests a less than one-year payback on its solar window product. Onyx also put out a nice PDF which breaks down solar glass efficiency versus visibility, and then gets into the costs of installation.
— Onyx Solar (@onyxsolar) March 27, 2018
California’s new net zero energy building laws – all new residential net zero by 2020, all new commercial net zero by 2030 and heavy retrofit requirements – point towards significant potential for solar glass. SolarWindow suggests that there is a $100 billion market for their product on the 5.6 million commercial structures in the United States alone. However, the long lifetime of buildings relative to new building construction and new solar power infrastructure may keep solar windows as a niche product.