Solar energy: Primary renewable energy

Solar power is a type of renewable energy that comes from sunlight. It harnesses energy from the sun to create clean, renewable energy. To meet global climate targets the world needs to transition away from fossil fuels – the biggest contributor to global warming – to clean, affordable energy like solar power as fast as possible. In this blog we cover how solar energy works, and some of the advantages and disadvantages of solar energy.

What is solar energy?

Solar power harnesses energy from the sun to create clean, renewable energy. Solar panels installed on roofs or in rows or clusters on land make electricity from the sun using photovoltaic panels. The more light the panels are exposed to, the more electricity they will be able to produce.

How does solar energy work?

The technology allowing us to harness energy from the sun has been around for a long time. In fact, the first proper solar panel was invented back in 1881. But it’s in the last 15 years that the technology has really taken off. Many people wonder how solar panels actually work. In short, solar panels absorb tiny particles of light called photons.

When the photons hit the panel, they dump their energy into it.
This energy finds its way to particles in the panel called electrons.
The added energy ‘excites’ the electrons and allows them to move around.
They move towards a metal strip called an electrode and this causes an electric current.
The current then flows out of the solar panel and into whatever it’s connected to.

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Advantages and disadvantages of solar energy

Now that we know more about how solar energy works, it’s time to look at some of the advantages and disadvantages of solar energy.

Advantages of solar energy

Solar power is a clean, renewable form of energy which has a crucial part to play in the transition towards a more climate-friendly energy system. Read on to learn more about some of the advantages of solar energy.

Solar power is a clean, renewable energy source

Solar power, like other renewable energy sources such as wind power, doesn't generate carbon emissions during electricity production. This makes solar power a climate-friendly alternative to non-renewable energy sources like oil, coal and gas.

Transitioning our energy systems to renewable energy is crucial to avoid the worst consequences of climate change. In fact, the UN and the International Energy Agency have concluded that there isn’t room for any new oil, gas or coal projects if we are to limit global warming to 1.5-degrees. To meet global demands for energy we therefore have to massively scale up renewable energy production.

Solar power is affordable

Technological innovation has significantly reduced the cost of solar panels over the last few decades. In many parts of the world, solar power is the cheapest form of energy available, and much cheaper than dirty fossil fuels like oil, gas and coal that contribute to climate breakdown.

The potential of solar power is huge, especially in many countries in the global south where sunlight is abundant. If we are to maximise this potential, governments need to put in place the necessary funding mechanisms and policies needed. Governments also has to ensure that fossil fuel companies are not able to block the transition by locking up capital, resources and infrastructure in fossil fuels.

Also in the global north, homeowners and businesses are embracing the potential of solar energy to reduce electricity costs and increase energy independence. In the UK – a country perhaps not known for its sunny weather – as much as 4.9% of households have solar panels. That's 1.4 million homes with solar installations as of June 2024, according to government data, out of 28.4 million households. Though solar panels require an initial investment, many will earn this investment back relatively quickly. In the US for example, the cost to install solar has dropped by more than 73 percent since 2006.

Solar panels are flexible

Solar photovoltaics (PV) is a very modular technology that can be manufactured in large plants to create economies of scale, but that can also be deployed in very small quantities at a time.

This means that solar panels can be installed in many different places, from small residential roof-top systems up to utility-scale power generation installations.

Solar farms have even been found to be compatible with farming: in the UK grazing sheep have been found to actually do better on land where there are solar panels.

Disadvantages

As with all technologies there are also some disadvantages and challenges associated with solar energy. Read on to learn more about some of these.

Reliability

Solar panels don’t produce energy all the time, because they take energy from the sun. However, the myth that solar panels need the sun to shine to produce energy isn’t correct: Solar panels will still generate electricity during cloudy weather, rain or any other period of indirect sunlight, just not as efficiently

That being said, producing energy from solar panels can be a challenge especially for countries with long winters with little daylight such as Norway. However, some supporting technology can still make solar power a reliable source of power. Batteries are the most common method of storing solar energy for electricity. In home solar thermal systems, solar panels are used to heat water, which is also a form of clean energy storage.

Solar panel production

To be a cheap, clean and accessible solution to climate change, the world is going to need a lot of solar panels. Solar panels are made from a variety of materials, including glass, silicon and metals like aluminum and copper. Sourcing these materials and producing solar panels requires mining, which can be harmful to the environment and workers.

To avoid these harms, the solar panel industry needs to be well-regulated – including mining and production. Recycling old solar panels is another way to help avoid mining more than necessary.

Plans for new solar panels need to consider the impact on nature

Even though solar power is a much greener alternative to fossil fuels, as with all infrastructure projects there will be some associated impacts on nature and emissions. Before any new solar power project is giving the go ahead, they should be subject to local planning considerations and appropriate biodiversity impact assessments.

However it’s important to remember that solar power is a much less damaging form of energy generation compared to fossil fuels, especially controversial methods such as fracking or tar sands.

Learn more about how fossil fuels impact biodiversity here.

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The future of solar energy

Solar power and other forms of renewable energy are at the center of the transition to less carbon-intensive and more sustainable energy systems. In 2023, solar PV alone accounted for three-quarters of renewable capacity additions worldwide, according to the International Energy Agency. Solar PV generation increased by a record 270 TWh (up 26%) in 2022, reaching almost 1 300 TWh. It demonstrated the largest absolute generation growth of all renewable technologies in 2022, surpassing wind for the first time in history.

Even though we’ve seen some great strides in ramping up renewable energy production, a lot more is needed if we are to succeed in decarbonising our energy systems. Fossil fuel producing nations and companies should bear the brunt of the investment needed. This is not happening at the moment: According to the IEA, oil and gas producers account for only 1% of total clean energy investment globally.

Another important consideration is where renewable energy is replacing fossil fuels. The biggest developments in recent years has happened in the electricity sector where there has been a significant growth of solar and wind power, building on the already significant contribution of hydropower. But electricity accounts for only a fifth of global energy consumption. Therefore, if we are to achieve the energy transition we need to find a greater role for renewable energy sources in transportation and heating.

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Equinor’s lack of investment in solar power

Equinor spends millions portraying itself as a broad energy company committed to the energy transition. When the company changed name from Statoil to Equinor in 2018, the then Communications Director of the company, Reidar Gjærum, wrote an article in a Norwegian financial paper explaining, among other things, the need to drop «oil» from the name: «We have chosen a name that signals an aspiration to contribute to shaping the future, to be competitive also in a low-carbon society. As a carbon-efficient producer of oil and gas, but also as a major supplier of energy from wind and solar.»

But the truth is very different from the brand Equinor presents. 99% of the energy that Equinor produces continues to be fossil fuels. Less than 1% of the energy it produces is renewable energy like solar and wind.

Equinor has on several occasions been forced to pull back adverts that give a misleading impression of the company’s commitment to renewable energy like solar power.

Conclusion

Solar power has a key role to play in the transition to a more sustainable and climate-friendly energy system. The companies and countries that have profited from the world’s reliance on fossil fuels should be at the forefront of investing in the transition. This is currently not the case.

That’s why it’s crucial that we continue to challenge companies like Equinor and countries like Norway to not open any new oil and gas projects, and instead use its capital, experience and expertise to scale up renewable energy production.

‍Learn more about how you can get involved in the Equinor Out coalition.