Is Solar Energy Renewable or Nonrenewable?

Renewable Energy vs. Nonrenewable 

Before diving into the question of whether solar energy is a renewable source, we must figure out the difference between renewable energy and the nonrenewable. 

Renewable energy refers to energy that can naturally replenish itself over a short period of time and will not run out within a reasonable human timespan, while nonrenewable energy is characterized by its limited supply and will eventually be exhausted within a relatively short-term future. 

For example, if we consume all the crude oil on planet Earth, because it is derived from ancient organic matter, it takes millions of years to regenerate. This literally means fossil fuels supply will no longer be available once depleted. According to a report of The World Counts in 2023, the global oil reserves are only about 1.5 trillion barrels. At the current rate of consumption, the supply of crude oil can only last about 50 years. 

In contrast, wind is a renewable energy source because it features quick, continuous replenishment and endless supply, allowing for a sustainable and effectively perpetual use of the energy. 

Is Solar Energy Renewable?

Solar energy is 100% renewable and it is regarded as one of the cleanest, most stable, abundant, and cost-effective energy sources. According to NASA, the sun is in its prime and will continue to fuel life for another 4.5 to 5 billion years. This means as long as the sun shines, we will have access to an infinite stream of solar energy. 

Solar energy is incredibly powerful. In just one hour, the sunlight hitting Earth's atmosphere can generate enough energy to power the world for a full year, assuming there are enough solar panels that can be deployed to collect the sunlight and facilities to store the energy. 

Is Solar Energy Green?

Solar energy is one of the most popular green energy solutions. Many people use green energy and renewable energy in an interchangeable way, but there are actually subtle differences between the two concepts. 

Renewable energy places  emphasis on the fact that it can be continuously self-replenished in a fast fashion, and these sources are inexhaustible over human timescales, whereas green energy is associated with little to no environmental impact during energy production. All green energy sources are renewable, but the reverse is not necessarily true. 

Solar energy is generally considered green. While the manufacturing of solar panels can involve some emissions, the amount is far lower than the amount of emissions avoided by using solar power over its long lifespan (typically from 20-25 years).

How Does Solar Energy Produce Electricity?

In a solar energy system, each solar panel is composed of layers, including photovoltaic (PV) cells, a metal frame, a glass cover surrounded by a protective film, and wiring. Each PV cell contains two semiconductor layers made of silicon, one with positive charge and the other with negative, forming an electric field. When sunlight (photons) strikes the PV cell, the energy from the sunlight knocks the electrons loose from the silicon atoms and causes them to move to generate a flow of electric current. 

This current is known as "direct current" (DC), not the alternating current (AC) most household appliances consume. Therefore, it is necessary to convert the DC electricity into AC using a device called an inverter before it powers your household devices. 

When solar energy produces electricity, zero greenhouse gases are released. This is seen in contrast to conventional fossil fuels, which discharge myriad amounts of toxic gases and other harmful particles during combustion.

Environmental Benefits of Solar Energy

Low Carbon Footprint

The manufacturing of solar panels currently involves some of the consumption of fossil fuels, as the power infrastructure still relies upon them. One example is in the extraction of raw materials such as silicon. This is one of the causes that can lead to the confusion of whether solar energy is renewable. However, as the manufacturing technology and productivity of PV panels continue to advance, the carbon footprint has significantly dropped. 

If the total amount of CO₂ emissions generated across all the stages of solar panel production, transportation, installation, and maintenance is converted to the average value per kilowatt-hour (kWh) electricity generation, according to the data of National Renewable Energy Laboratory (NREL), solar systems only produce 40 g carbon dioxide per kWh over their entire lifecycle, which is in stark contrast to over 1,000 g per kWh from coal-fired power plant, not to mention some old plants in particular regions where the number can exceed 1,500 g. 

That low footprint means a typical solar panel can achieve carbon neutrality in only 2 to 3 years. From that on, solar panels are completely carbon-free for the remaining 20-25 years of guaranteed life. 

Meanwhile, over the last decade, good news for the solar industry is that the average cost of solar systems has witnessed a drastic drop, falling by approximately 90% from $4 per kW to less than $0.50 today (LBNL). This will no doubt make solar power far more accessible and will hopefully elevate its utility rate to another level, lowering the global carbon footprint exponentially in the future. 

Zero Environmental Impact on the Landscape 

All solar systems (whether installed on the rooftops, ground or a floating platforms) are non-invasive to the local landscape. The rooftop installations, for example, take advantage of the existing structures without disturbing the natural landscape. It will not occupy too much space or alter the natural form of the environment. There is also zero leakage of toxic chemicals that can contaminate the soil and water during their operational life, which is commonly found on fossil fuels during mining and burning. 

A Renewable Energy not Restricted by National Boundaries

Unlike fossil fuels that may be concentrated in specific countries with abundant reserves and require costly extraction, solar energy is free, boundless and universally accessible to all humanity regardless of nationality and race. Even in far north countries, where sunlight is less frequent, such as Northern Europe, people living in the region can still enjoy the use of solar energy by investing in sufficient panels and infrastructure to handle the additional photovoltaic energy storage. 

Solar energy also significantly reduces imports of fossil fuels due to scarcity in many countries. A statistical report from the World Economic Forum showed up to $29 billion has been saved in Europe in fossil fuel imports during the summer of 2022 by enlarging their solar energy capacity. 

How to Make Solar Energy More Environmentally Friendly?

Maximize the Use of Solar Energy

While solar energy is incomparably abundant, it does have some drawbacks. Solar energy can only be harnessed during peak sunlight hours and it is not accessible at night or on overcast days. This means the surplus energy generated can go to waste. To maximize the use of renewable solar energy, the solution lies in integrating a solar battery that can store the excess energy for use when there is no or insufficient sunlight. 

The development of battery energy storage technology, is the catalyst for the wider expansion of solar systems, enabling the availability of large-scale solar power plants such as solar farms, which contribute immense amounts of electricity to the grid, accelerating the transition towards more renewable energy. 

The global energy storage market sees an impressive annual growth of 20% and is expected to rise to the scale of hundreds of billions of US dollars by 2030 (BloombergNEF, Allied Market Research). FranklinWH is one of the pioneering leaders. Its flagship solar battery, aPower 2, boasting an unparalleled 15 kWh capacity, is compatible with all solar inverters. Paired with solar panels, a single unit is enough for 24/7 whole-home backup, even in 100% off-grid situations. It serves as the best companion for solar systems, helping to power your home more effectively and facilitating a more sustainable life. 

Recycling of Solar Panels

Recycling solar panels can also improve the eco-friendliness of solar energy by addressing waste and other environmental issues associated with old panel disposal.

Solar panels are made of silicon glass, aluminum, gallium, indium and other similar valuable metals. A significant amount of these metals is recovered during the recycling process and this helps to preserve some materials as it reduces the extraction of new raw materials.

Wherever these panels are used, the lead contained in the electronics and cadmium in the thin films also present a danger if they are not correctly handled. When materials are recycled, these toxic substances are safely removed to prevent pollution of land and waters with these chemicals.

Also, when such materials are recycled, there is no need for energy processes usually required for the making of new panels from raw materials, thus reducing greenhouse gases.

Final Thoughts

As the epitome of renewable energy, solar energy plays a pivotal role in global energy transition. As of 2023, 30% of the world's electricity is generated by renewable energy, of which solar energy accounts for nearly 10%. According to McKinsey's research, renewable energy will dominate the global energy mix by 2050, accounting for 65% to 85%. This is of strategic importance in mitigating climate change. The advancement of renewable energy, particularly PV, is driving down energy costs significantly. This further enhances the attractiveness and importance of renewable energy.