Renewable energies Connect. Connect. Renewable energies

Water

Wind power

Bioenergy

Solar

Oceans

Geothermal

What are they?

Renewable energy sources are natural resources capable of regenerating themselves in a short period of time and in a sustainable way.

Geothermal energy, biomass, tidal and wave power, wind, sun, and water are examples of renewable energy sources. These sources prevent the need to import fossil fuels such as coal and natural gas to generate electricity, avoid the emission of greenhouse gases, and reduce the price of electricity in the market, contributing to greater economic and environmental sustainability for the country.

Water

Hydropower production occurs in hydroelectric power plants, which can be of two types: those with reservoir storage or run-of-river. Small hydroelectric power plants have a power output of up to 10 MW, while large plants exceed this value. The operation of hydroelectric power plants is based on the difference in height between the reservoir level (upstream) and the river level downstream. This difference in potential energy is converted into mechanical energy by rotating the blades of a turbine, which, in turn, drives the generator responsible for electricity production.
In the case of run-of-river power plants, there is no reservoir; only the natural flow of the river is used whenever available. Hydropower plants are one of the most efficient forms of electricity generation and play an essential role in the stability of the electrical system. Currently, in an average year, about 30% of the electricity consumed in Portugal comes from hydropower.

Wind power

Wind is the movement of air masses generated by the uneven heating of the atmosphere and the orography of the terrain. Throughout history, it has been used to propel sailing vessels, grind grain, and pump water from wells. Today, it plays a fundamental role in the production of electricity through wind energy.

Wind farms are installed in locations where the average annual wind speed exceeds 6 m/s, which, in Portugal, occurs mainly in mountainous areas and along the coast. In these plants, wind turbines convert the force of the wind into electrical energy: the blades capture the kinetic energy of the wind, causing the generator shaft to rotate, which produces electricity.

In addition to onshore wind farms, there are also offshore wind farms, which take advantage of more consistent and intense winds, as well as the vast area available.

However, their implementation requires consideration of restrictions such as fishing zones, protected areas, and shipping routes. Currently, about 25% of the electricity consumed in Portugal comes from wind power, making this energy source an essential pillar of the national electricity system.

Bioenergy

Bioenergy is a renewable energy source derived from organic matter, whether of plant, animal, or waste origin. Throughout history, it has been used primarily for heating and cooking, but currently, it plays an important role in electricity production and in reducing dependence on fossil fuels. Energy generation from bioenergy occurs through direct combustion, gasification, or anaerobic digestion, processes that allow the conversion of organic matter into heat, electricity, or biogas. In Portugal, forest bioenergy is one of the main sources used, contributing not only to energy production but also to the sustainable management of forests and the reduction of fire risk.
In addition to solid bioenergy, liquid biofuels, such as biodiesel and bioethanol, as well as biogas, are playing an increasing role in the energy transition, representing sustainable alternatives for the electricity and transport sectors. Currently, bioenergy accounts for a significant fraction of renewable electricity production in Portugal, reinforcing the diversification of the energy mix and the decarbonization of the economy.

Solar

Electricity production from the sun can be done through photovoltaic or thermal solar panels. In the case of photovoltaic panels, the photovoltaic cells capture solar radiation and convert it directly into electricity. Thermal solar panels, on the other hand, use mirrors to concentrate sunlight and heat a fluid, generating steam. 

In addition to generating electricity, solar energy can also be used for water heating in homes, buildings, and industrial processes, reducing the need for electricity or gas.

Oceans

The oceans are an abundant source of renewable energy. However, equipment to convert this energy into electricity is still under development, focusing on improving efficiency and resistance to the marine environment. In Portugal, Pico Island, in the Azores, is home to a 400 kW power plant, the first in the world to regularly produce electricity from wave energy. Furthermore, along the Portuguese coast, various technologies have already been tested, and the São Pedro de Moel Pilot Zone, located between the ports of Figueira da Foz and Nazaré, covering approximately 320 km², with depths varying between 30 and 90 meters, is operational, serving as a space dedicated to the demonstration and development of innovative projects for harnessing wave energy.
In addition to wave energy technologies, the pilot zone also includes offshore wind energy projects, such as WindFloat, an innovative system of floating wind turbines. This project aimed to explore the potential of wind energy at sea, since offshore areas can provide more consistent and intense winds than coastal regions. WindFloat is a floating platform designed to support wind turbines in deeper waters, an advantageous solution for locations where the installation of fixed structures would not be feasible.

Geothermal

Geothermal energy is generated from heat originating from the Earth's interior. Regions with volcanic activity, such as magmatic intrusions and geothermally active areas, have a high potential for this type of energy.
Electricity can be produced in geothermal power plants, where the Earth's heat generates water vapor that moves the blades of a turbine. This rotary motion is transferred to the shaft of a generator, which transforms mechanical energy into electricity.

In Portugal, the Azores Autonomous Region is home to several geothermal electricity production units, serving as a pioneering example in the use of this renewable source.
In addition to electricity generation, geothermal energy is widely used for heating and air conditioning, being applied in agricultural greenhouses, thermal baths, industrial processes, and building heating or cooling systems through geothermal heat pumps.