Renewable energies, also known as clean energies, are increasingly used across the globe. Solar cells are costing lower than before and solar energy supply capacity is increasing. Studies predict that in coming years, more solar cells would be installed across the world with 1TW capacity.
In the Middle East region with known huge fossil resources, solar cells are forecast to make up 9% of total world capacity, up from the current 3%. The main reason for switch to solar energy is increased demand for electricity in the world. Since solar panels reduce power generation costs, the electricity generation prices would become more competitive and solar energy construction would become more economical.
Iran enjoys high capacity in renewables. In addition to policymaking, the government has formulated plans to encourage investment in renewable energy. Some pilot projects like Manjil and Dizbad wind farms and solar power plants in Semnan and Yazd have already become operational.
The trend pursued in recent years has presented attractive tariffs for guaranteed supply of electricity generated from renewables. That has accelerated construction of renewable power plants, particularly photovoltaic solar power plants, by private sector investors. Significant photovoltaic solar power plant capacity has been installed in Iran.
Renewable energies are clean alternatives to fossil fuels. Despite having their own challenges, the renewables produce less pollution, emit less greenhouse gas and are inexhaustible.
The main sources of renewable energy are reviewed briefly. A key point with Iran’s geography is that it has capacity to develop many, if not all, such sources of energy. However, it depends on access to necessary technology at affordable costs.
Iran currently enjoys good potential to produce solar energy and some companies involved in the petroleum sector have moved to supply their electricity needs from solar energy.
The Sun is the most powerful source of energy. Sunlight or solar energy may be used for heating, lighting and cooling houses and buildings, power generation, heating water and a variety of industrial processes.
The technology used in producing solar energy is changing constantly. Rooftop solar water heating pipes, photovoltaic cells and mirror arrays are cases in point. Rooftop panels impose nothing on nature, but large arrays installed on earth may interfere with the wildlife habitats.
Wind is the movement of air. Wind starts blowing when hot air rises and cooler air moves to replace it. Wind energy has long been used to move sailing ships and running mills to crush grains. Today, it is used for running turbines to produce electricity.
There is often speculation about where these turbines must be installed as they may cause problems for migratory birds and bats.
Water running downstream generates a powerful force. Water is a renewable source and is constantly replaced by the global cycle of evaporation and precipitation. The Sun’s heat causes sea and ocean water to evaporate, forming clouds. Then water returns to the earth through rainfall or snowfall and runs into rivers and streams flowing into oceans.
The running water’s energy, which is controlled by turbines and generators (like what is seen in dams), may be used for generating electricity. Even small turbines may be used to supply energy to each and every single household.
Hydroelectric energy is renewable, but on a large scale it may cause serious damage to the environment.
Ever since mankind burnt wood for cooking and heating in winter, biomass has been a key source of energy. Wood is still the most common source of biomass energy. Other sources of biomass energy include food products, grass and other plants, detritus, agriculture and forestation wastes, organic elements of urban and industrial refuse and even methane produced in landfills.
Biomass may be used to generate electricity or power vehicles. It may also replace non-renewable fossil fuel used in some production chains.
Hydrogen is a power fuel and source of energy. It is the most abundant element found on the earth. For instance, hydrogen makes up two-thirds of water, but in nature it is always found in compounds.
When hydrogen is separated from other elements it may be used to power vehicles, replace natural gas in heating and cooking and also to generate electricity. In 2015, the first hydrogen-powered car was produced and distributed in Japan and the United States.
The thermal energy coming from the subsurface of the earth can produce hot water and steam to run power generators, heat houses and produce energy for industrial purposes. Geothermal energy may be obtained by drilling into deep subsurface reservoirs or geothermal reservoirs closer to the surface of the earth. This source of energy is being increasingly used to balance heating and cooling costs in residential and commercial buildings.
Oceans offer several forms of renewable energy, each of which directed and controlled by different forces. The energy produced through tidal waves of oceans may be used to generate electricity. So is power generated from the thermal energy stored in seawater.
With existing technologies, marine energy is often less economical than other sources of renewable energy. However, oceans continue to remain a potential source of energy for the future.