# Wind Turbine Blades with Noise-Reducing Serrated Edges > This patent describes a wind turbine blade design that reduces noise by attaching a special serrated plate to its trailing edge, integrated directly into one of the blade's outer surfaces. - **Patent:** US 8932024 - **Original title:** Wind turbine blade and wind power generator using the same - **Owner:** Mitsubishi Heavy Industries - **Granted:** 2015 - **Status:** Active - **Times cited:** 20 - **Field:** energy, mechanical, aerospace, materials ## What it does The patent describes a wind turbine blade made from a "back skin" and a "front skin" bonded together. To reduce noise, a "serrated plate" is attached to the "trailing edge" (the back edge) of the blade. This plate has a wavy, saw-tooth-like "serrated portion" on its rear side. A key part of the design is how this plate is attached: it's formed as a single piece with either the back or front skin (Claim 1 specifies it's part of the back skin). The other skin then has a "fitting portion" (a semicircular bump) that locks into a "fitting groove" (a semicircular dip) on the serrated plate, securing the plate firmly. This specific attachment method ensures the serrated plate is precisely positioned to smooth airflow and suppress noise. For example, a wind turbine blade could have this serrated plate integrated directly into its back surface, with the front surface snapping into place to complete the blade and secure the noise-reducing feature. ## What it does NOT cover - Serrated plates that are simply glued or bolted onto the trailing edge without the specific "fitting groove" and "fitting portion" described in Claim 1. - Serrated plates that are separate components and not formed integrally with one of the blade skins. - Noise reduction methods for wind turbines that do not involve a serrated plate at the trailing edge. - Serrated plates that do not have a serrated portion on their rear side. - Blades where the serrated plate is not disposed along the wind flow at the trailing edge. ## The clever bit The novelty lies in the specific, integrated attachment mechanism for the serrated plate. By forming the serrated plate integrally with one blade skin and using a precise fitting groove and portion for the other skin, the patent ensures robust attachment and accurate positioning of the noise-reducing feature, which is critical for aerodynamic performance and durability. ## Real-world examples 1. Modern large-scale wind turbine blades 2. Offshore wind farm turbines 3. Wind turbines designed for urban or suburban areas 4. Turbine blades from manufacturers like Siemens Gamesa, Vestas, GE Renewable Energy ## Why it matters Wind turbine noise, especially from the blade tips, is a significant concern for communities near wind farms. This patent addresses that issue by proposing a specific design for noise reduction. Quieter turbines can lead to broader acceptance and allow wind farms to be built closer to populated areas, increasing renewable energy capacity. ## Frequently asked questions ### What does Wind Turbine Blades with Noise-Reducing Serrated Edges cover? This patent describes a wind turbine blade design that reduces noise by attaching a special serrated plate to its trailing edge, integrated directly into one of the blade's outer surfaces. ### Who owns patent US 8932024? Mitsubishi Heavy Industries owns this patent, granted in 2015. ### When does this patent expire? This patent is expected to expire on August 6, 2028, when the invention enters the public domain. ### What is patent US 8932024 cited by? This patent has been cited by 20 later patents that build on its ideas. ### What problem does this patent solve? Wind turbine noise, especially from the blade tips, is a significant concern for communities near wind farms. This patent addresses that issue by proposing a specific design for noise reduction. Quieter turbines can lead to broader acceptance and allow wind farms to be built closer to populated areas, increasing renewable energy capacity. ### What does this patent NOT cover? Serrated plates that are simply glued or bolted onto the trailing edge without the specific "fitting groove" and "fitting portion" described in Claim 1. **Full plain-English explainer:** https://patentbrief.org/patent/us/8932024/wind-turbine-blade-and-wind-power-generator-using-the-same **Original patent:** https://patents.google.com/patent/US8932024 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How Wind Turbine Blades Get More Lift with Extra Parts](https://patentbrief.org/patent/us/8303250/method-and-apparatus-for-increasing-lift-on-wind-turbine-blade) — This patent describes adding special front and back parts to a wind turbine blade to create specific air channels, making the blade generate more power from the wind. - [Making Iron More Efficiently and Generating Power with Oxygen](https://patentbrief.org/patent/us/8133298/blast-furnace-iron-production-with-integrated-power-generation) — This patent describes an integrated system that uses extra oxygen in a blast furnace to make iron more efficiently, while also capturing the furnace's waste gases to generate electricity and reduce carbon dioxide emissions. - [Capturing Carbon Dioxide While Making Electricity with Hydrogen and Solar](https://patentbrief.org/patent/us/12327854/apparatuses-and-methods-for-carbon-dioxide-capturing-and-electrical-energy-produ) — This patent describes an integrated system that captures carbon dioxide from the air or industrial exhaust while simultaneously generating clean electricity using a hydrogen gas turbine powered by solar-generated hydrogen and oxygen, all without burning fossil fuels. - [How the String Trimmer (Weed Eater) Actually Cuts Grass](https://patentbrief.org/patent/us/3826068/weed-eater-string-trimmer) — This 1974 patent describes the mechanics of using a high-speed spinning plastic line to cut grass, replacing dangerous metal blades with flexible, non-metallic material. - [How to Make Solar Troughs Catch More Sunlight at Their Ends](https://patentbrief.org/patent/us/8049150/solar-collector-with-end-modifications) — This patent describes adding special reflective extensions and caps to the ends of a single-axis tracking solar trough to capture more sunlight that would otherwise be lost, making the collector more efficient.