The Sun's energy is renewable and clean. But what about solar panels?
Michael Moore's last movie, Planet of the Humans, questions the reliability, affordability and sustainability of renewable energy.
The thought-provoking film also highlights the renewables' dependence on fossil fuels.
Ultimately, the message conveyed by Moore is renewable technology is not enough to save our planet from climate change and the only way forward is for the human race to slow down.
How green are renewables?
Following Moore's movie broadcasting, various climate experts signed a letter where they claim scientific and technological advancements made renewable energy alternatives more viable and cheaper to run than fossil fuels.
According to a recent report published by the International Renewable Energy Agency (IRENA), it is now more convenient to build new solar photovoltaic (PV) and wind farms than running existing coal plants. This seems to back up Moore's movie detractors.
Moreover, as suggested by the Intergovernmental Panel on Climate Change (IPCC) Special Report on Renewable Energy Sources and Climate Change Mitigation, renewable energy is much better than fossil fuels exploitation in terms of sustainable development (unlike someone in Moore's movie suggested).
What are the limitations of renewable technologies?
Although science firmly disagrees with Moore's views, Planet of the Humans raised valid points on the weaknesses of the most extensively used renewable energy sources.
Solar and wind
Over the quarter of 2020, up to 47% of the electricity demand in the UK was met by renewable energy sources. This record was hit largely thanks to a significant upswing in the energy generated by wind farms and solar arrays.
Nevertheless, solar panels and wind turbines share a series of drawbacks: a fossil-fuelled fabrication process, unsustainable raw materials, intermittency, and a short lifespan ( typically up to 25 years).
During the heatwave which hit California last August, grid operators had to impose rolling blackouts due to the extreme surge in energy demand.
One reason leading to this drastic measure was the insufficient power supplied by solar and wind altogether, which normally provides 30% of the overall electricity in the California State. This spotlighted the faults of high-renewables grids, which will need long-duration energy storage technologies to become more resilient.
Biomass
Biomass (or bioenergy) is one of the latest energy sources jumping on the renewable-fuelled bandwagon, yet the most controversial one.
In the UK, the energy produced from biomass currently accounts for ca. the 25% of the total renewable energy share.
Following biomass being granted the "clean energy" label, increasing funds have been invested in wood-fired power plants.
However, the think-tank Sandbag claimed the deforestation induced by wood's high demand will cancel out the benefit of not burning coal, thus boosting climate change rather than mitigating it.
This is because the new trees will not have the time to grow and capture the carbon dioxide emitted during biomass combustion, thus preventing the process from being carbon neutral. On top of that, most of Europe's wood supply comes from the US and Canada, which implies an additional carbon footprint due to transportation.
What's the foreseeable future of renewable energy?
A group of researchers envisioned that, despite social and political challenges, it would be realistic to have 100% wind, water, and solar (WWS) on a global scale by 2050. On the other hand, scientists also concluded individuals should do their part by transitioning their homes and lives.
Based on what argued above, renewables will have a crucial role in the struggle against climate change, yet further research will be required to disentangle clean energy technologies from fossil fuels. Furthermore, people will have to play their part in resolving the energetic conundrum through a more diligent and eco-friendly power usage.