Is Solar Energy Renewable or Non-renewable?

Solar energy is considered today a clean energy source due to the fact that the solar cells used by solar PV panels and the mirrors used by solar thermal power plants are not releasing emissions while producing clean electricity.

A renewable energy source is a source of power that never ends because it is continuous.

A non-renewable energy source uses a finite resource of power, a resource that is non continuous, so will be depleted sooner or later.

Is Solar Energy Renewable?

Solar energy is considered a renewable energy source because we are using the sunlight to generate electricity.

The sunlight is produced by the Sun, which is considered a renewable resource of power on a human timescale because it will be here to send us light and heat for another 5 billion years.

The Sun produces energy and light due to the nuclear fusion reaction that takes place every second in our star.

During the nuclear fusion reaction that takes place in the core of the Sun, hydrogen is turned into helium and a large amount of heat and light is released in the process.

The age of the Sun is estimated at 4.6 billion years, and scientists are saying that our star has already consumed half of its hydrogen fuel, which means that the Sun can send as energy under the form of heat and light for another 5 billion years from now on.

It is estimated that when the Sun will consume all its hydrogen fuel will start fusing helium and other heavier elements until will completely run out of fuel.

Examples of Renewable Energy

All the energy sources that are continuous (they never end compared to our timescale here on the planet) are the following: solar energy, wind power, geothermal energy, water energy (hydropower, tidal and wave energy) and biomass.

In a not so far future, the nuclear fusion reaction of hydrogen could also become a renewable energy source due to the fact that hydrogen is a very abundant element here on the planet and in the known universe.

1. Solar energy

To produce solar energy (clean electricity) we are using today photovoltaic (PV) solar cells or large mirrors that are concentrating the sunlight towards the top of a central tower where an agent such as molten salt is heated at high temperatures to generate steam that will be used to spin a turbine and produce clean electricity with the help of generators.

Solar cells are converting the sunlight into clean electricity, which can be stored in battery systems (for later use) or can be used (after the conversion from DC to AC) by the grid and inside the house to power appliances.

Solar panels cost is no longer so high due to the fact that the PV technology is now produced not only in the U.S. or in the EU, but mainly in Asia.

2. Wind Power

The wind on planet Earth is also produced by the Sun because our star heats the different layers of the atmosphere in an uneven way, which makes the warm layers of air to move up, and the cold layers of air to move down.

This movement of the air layers in our atmosphere is called wind, and is produced by the Sun, which means that the wind is another form of renewable energy produced by the same renewable resource, which is the Sun.

Wind power works very well in the UK, but we also have there many solar distributors, and this means that solar panels UK is also a good choice for going solar.

3. Geothermal Energy

Geothermal power is the heat that comes from the underground, and is produced by the core of our planet.

The core of planet Earth is also called “the Inner Sun” because it’s temperature is higher than the temperature of the Sun’s surface (6,000 K compared to 5,000 K).

Geothermal energy reaches the surface of the planet under the form of hot steam and water (the temperature of the water is around 300°C).

Geothermal power is used today in residential heating and cooling, but also to generate clean electricity (the hot steam is used to spin a turbine that will produce green electricity using generators).

4. Water Energy

Water is a great renewable energy resource here on the planet because it sustains all the life on Earth and is also a good source of clean energy.

Hydroelectric energy or simply hydropower is the most developed renewable energy source today (has the highest share among all the renewables in the energy mix of many countries).

Hydropower is produced today in hydroelectric power plants that are using the kinetic energy of the falling or fast-moving water (streams), which spins underwater turbines to produce electricity with the help of generators.

Tidal energy is another form of water power, but is produced by the tides on our planet.

The tides on planet Earth are produced by the gravitational forces of the Sun, Moon and Earth combined.

The tides are pretty constant (we have two high tides and two low tides during a 24 hour period), which means that we can calculate the capacity to produce clean energy even before building a tidal energy power plant.

To harness the kinetic energy of the tides, mankind uses today strong underwater turbines that feature a pretty large hole in their center, which is used by marine life as an escaping corridor from the spinning turbine.

Wave energy is another form of water energy that uses the kinetic energy of the waves, and the pressure fluctuations below the surface of the water to generate clean electricity.

5. Biomass

Biomass is considered a renewable energy source because wood is a renewable resource (trees regrow), and the human trash and also the human and animal organic waste are produced continuously.

All these waste materials are used today to produce biomass energy, which is a renewable energy source, but is not 100% clean because it releases a certain amount of harmful emissions into the atmosphere while burning.

Biomass is used for heating, cooking, but also to generate low-carbon energy.

Examples of Non-renewable Energy

Non-renewable energy sources represent all the energy resources that are finite.

We can include here all the fossil fuels (coal, oil and natural gas) and nuclear energy (nuclear fuels used today in the nuclear fission reaction such as uranium, plutonium and thorium).

1. Coal

Coal is considered today the most dirty and harmful fossil fuel because it releases a very large amount of harmful emissions into the atmosphere while burning.

Even so, coal is a main source of energy in the energy mix of the planet, and this is one of the reasons why the planet is so polluted today.

Coal is a finite resource that will be completely depleted during this century.

2. Oil

Oil is a liquid fossil fuel that is mostly used as fuel in our vehicles (gasoline and diesel fuels are produced from oil), but is also used in the chemical industry and in the energy sector.

Oil is another dirty resource of energy that releases harmful emissions into the atmosphere while burning, and will be completely depleted around the year 2052.

3. Natural gas

Natural gas is considered the cleanest fossil fuel used today because it releases a small amount of harmful emissions into the atmosphere (compared to coal and oil) while burning.

Natural gas is a fossil fuel resource that will be completely depleted around the year 2060 (if we increase the actual consumption of natural gas while reducing the consumption of coal and oil to lower the emissions).

Natural gas is used for heating and cooking. but also to generate clean electricity.

4. Nuclear energy

We are producing clean electricity today in the nuclear power plants by using uranium, plutonium and thorium as nuclear fuels in the nuclear fission reaction that takes place in the reactors of these power stations.

However, besides clean electricity and heat, the nuclear fission reaction also produces nuclear waste, which is hazardous and very expensive to dispose.

Nuclear energy is considered a non-renewable energy source because all the nuclear fuels used today in the nuclear fission reaction (uranium, plutonium and thorium) are finite resources (thorium is more abundant than uranium and plutonium, but is still a finite resource).

Final conclusion

Because the Sun will be here for another 5 billion years to send us light and heat, we can say that solar energy is one of the greatest and easiest ways of producing clean electricity today.

Solar energy is a renewable energy source that is also clean (no emissions), which means that is one of the green sources of power that will replace the dirty fossil fuels in the clean future that will follow.