Wind Energy: history, technology, and Plenitude projects

Wind energy in history

The idea of exploiting wind power dates back millennia. The first windmills appeared in Persia as early as the 7th century AD, while in Europe they became widespread during the Middle Ages. However, only in the 19th century, with the advent of electricity, did the idea develop of transforming the wind’s kinetic energy into electrical energy.

Our history of wind energy begins here, with the pioneering attempts to combine an ancient technology like windmills with electricity.
 

What is wind energy and how does it work

To explain wind energy, we start from when the wind meets the blades of a wind turbine, which are aerodynamically shaped like an airplane wing. As wind flows over the blades, it creates a pressure difference between the upper and lower surfaces, generating a lift force that causes the blades to rotate around the main shaft. This rotary motion is transmitted inside the nacelle, where a gearbox accelerates the shaft’s motion up to 1,500-1,800 revolutions per minute. The main shaft, which operates at low rotational speeds, is connected to a gearbox that transfers kinetic force to an electrical generator. This generator, using the principle of electromagnetic induction, converts mechanical rotational energy into electrical energy in the form of alternating current (AC) at the grid frequency. After being stepped up in voltage by a transformer, the electricity is fed into a substation, which further increases the voltage to match the public grid requirements, allowing it to be distributed into the network.

The Main Components of a Wind Turbine:

Onshore and Offshore: where we capture the wind

Wind turbines, although installed at significant distances from each other, are often grouped to form what are known as wind farms. These can be located on land (onshore) or in open sea (offshore).

• Onshore: wind farms are built on land, often in rural or hilly areas where wind blows more intensely. The proximity to the grid reduces energy loss during transmission, while construction and maintenance, which are generally straightforward, support local economic development.
• Offshore: these wind turbines are installed in open sea, often at considerable distances from the coast. They take advantage of stronger and more constant winds, leading to higher and more predictable energy production compared to onshore farms. Depending on the water depth and seabed conditions, they can be installed on fixed foundations (monopile, gravity base) or floating structures. Offshore wind farms are more complex and costly to install and maintain, but their superior capacity offers immense potential for wind energy growth.

The advantages of wind energy

Like other renewable energy sources, wind energy offers significant benefits, contributing to the energy transition and positively impacting the economy and employment. Here are the main advantages.

• Abundance and unlimited supply: wind energy is derived from an infinite, inexhaustible, and widely available source worldwide. It can be harnessed even in areas that would otherwise be unproductive or considered uninhabitable.
• Vertical development: since turbines extend in height, surrounding land remains available for other productive activities such as agriculture.
• Job creation: the wind sector, like other renewable energy sources, generates employment in various phases, from manufacturing and installation to management and maintenance.
• High efficiency rate: according to Betz’s law, 59.3% of the wind’s kinetic energy can theoretically be converted into electricity. Though this is a theoretical maximum, it remains an impressive efficiency level.

* Calculation based on the estimated average annual electricity consumption in Italy of 2,700 kWh/year, according to data published by ARERA in the 2023 Annual Report.