Wind energy in the United States helps avoid 336 million metric tons of carbon dioxide emissions annually—equivalent to the emissions from 73 million cars. Further, wind energy provides 10% of total electricity nationwide, and more than 60% of power in Iowa, and over 40% of power in South Dakota, Kansas, and Oklahoma. Harnessing energy from wind turbines is not only an essential utility in the United States, but it also important to building a clean energy economy. IEC 61400-1 Ed. 4.0 b:2019: Wind Energy Generation Systems – Part 1: Design Requirements covers design specifications of wind turbines.
Renewable Energy– Wind Power
Wind power is the largest source of renewable energy in the United States, providing clean electricity to individual homes, remote farms, small communities, and large cities. Wind turbines harness energy from the wind using mechanical power to spin a generator and create electricity. Not only is wind an abundant and inexhaustible resource, but it also provides electricity without burning any fuel or polluting the air.
What Is IEC 61400-1 Ed. 4.0?
IEC 61400-1:2019 specifies essential design requirements to ensure the structural integrity of wind turbines. It covers the engineering and technical requirements to ensure the safety of the structural, mechanical, electrical and control systems of the wind turbine are given in the following clauses.
Further, this standard is concerned with all subsystems of wind turbines such as control and protection functions, internal electrical systems, mechanical systems and support structures. IEC 61400-1:2019 also provides an appropriate level of protection against damage from all hazards during the planned lifetime of wind turbines. It is applicable to wind turbines of all sizes. For small wind turbines, IEC 61400-2 can be applied. IEC 61400-3-1 provides additional requirements to offshore wind turbine installations.
This part of IEC 61400 Series for Wind Turbines outlines minimum design requirements for wind turbines and is not intended for use as a complete design specification or instruction manual.
How Do Wind Turbines Work?
Wind turbines work like a fan, but instead of using electricity, wind turbines utilize wind to create electricity. Wind turbines, like windmills, use propeller-like blades to catch the wind’s kinetic energy. Wind flows over the blades causing lift—similar to the effect on airplane wings. This stimulates the blades to turn. Large blades on the turbine rotor are connected to an electrical generator via a shaft and a series of gears. The blades of a turbine are around a rotor that spins an electric generator thereby producing electricity.
Turbine to Transmission Grid
By having an array of wind turbines in the same site, wind power plants are able to produce electricity. Factors such as wind conditions, the surrounding terrain, and access to electric transmission effect the placement of wind turbines. Electricity from the wind turbine generator travels to a transmission substation. At the station, the electricity is converted into extremely high voltage: between 155,000 and 765,000 volts. Now, the electricity can travel for long distance transmission on the transmission grid. The grid comprises a series of power lines that connect the power sources to demand centers, enabling electricity to powers our communities.
Horizontal and Vertical Turbines
Turbines are oriented differently due to the direction of the wind. The propeller-like blades on a wind turbine can have a horizontal axis or a vertical axis. This means that turbines either spin on an axis that is parallel to the direction of the wind (i.e., horizontal axis), or turbines spin when they are perpendicular to the direction of the wind (i.e., vertical axis). Horizontal axis turbines resemble the shape of a fan; whereas vertical axis turbines can resemble the shape of a merry-go-round, eggbeater, or windmills. A tall tower with three large blades on a horizontal axis is the most common wind turbine design.
Wind Turbine Design
IEC 61400-1:2019 describes information on how to properly install, assemble, and erect wind turbines. This can include, for example:
- Any training or competence standards recommended or mandated to enable contractors to undertake the installation safely and in accordance with local rules
- Details on the correct sequencing and assembly of the turbine installation
- Any specified loads or environmental conditions (e.g., wind speeds), including specified limits that need to be observed or not exceeded with specific reference to the installation
- of the tower and blades
- Technical, health, and safety information regarding tower, blade, and nacelle installation; any other structure or system being installed (e.g., gearbox); installation of anchors or any equivalent system; and the safe use of any specified equipment (e.g., cranes and lifting equipment) as part of the installation of the turbine
IEC 61400-1 Ed. 4.0 b:2019: Wind Energy Generation Systems – Part 1: Design Requirements is available on the ANSI Webstore as well as in the following standards package, IEC 61400-25 – Wind Turbines Communications Package.