NOVEMBER 28 –– As the world transitions away from fossil energy, solar is seen as the best candidate. Many see solar photovoltaic (PV) technology as a critical tool in the transition to renewable energy. The solar PV industry has mushroomed everywhere, Malaysia included. China has emerged as the world leader in the manufacture of the solar cells. Most others are mainly assemblers. The reasons for the popularity of solar are obvious. The rays from the sun are completely free. For generating energy there are two solar options. One is the solar PV. The other which has not been much explored is to use the solar heat to run turbines for electricity. Though solar PV has become the preferred option, several questions have been raised regarding its sustainability.

Solar PV manufacturing requires material sourcing and mining. This is a concern as the world struggles with the issue of resource scarcity. Solar PV systems rely on materials like silicon, silver, and rare earth elements (e.g., tellurium, indium, gallium). Mining these resources can lead to habitat destruction, water pollution, and human rights concerns. There are supply chain impacts. The environmental and social impacts of extracting, processing, and transporting these materials are often not adequately addressed in sustainability assessments of solar energy systems.

There is also the concern over energy and emissions during manufacturing. The manufacturing of solar PV panels, especially the silicon-based ones, is energy-intensive. While the energy payback time, the time required for the solar panel to generate the amount of energy used in its production, is relatively short, questions about the sources of this manufacturing energy, often derived from fossil fuels, are raised. The production process is known to involve emissions of greenhouse gases, such as sulphur hexafluoride (SF6), which has a significantly higher global warming potential than CO2.

A bigger concern is the end-of-life management and recycling, in short waste generation. Solar panels have an average lifespan of 25-30 years. As the industry grows, concerns arise over how to manage the increasing number of decommissioned panels. Without proper recycling infrastructure, these could lead to large amounts of hazardous waste. Recycling challenges have been raised. The materials used in PV systems are often difficult to recycle efficiently. Separating components like silicon, glass, and rare metals can be costly and energy-intensive, and existing recycling processes are not yet widely implemented.

Land use and habitat disruption have been raised as well. Large-scale solar farms require significant land areas, which can lead to habitat disruption, especially in ecologically sensitive areas. Questions about whether solar PV installations can coexist with natural ecosystems arise, particularly for ground-mounted solar farms. The land used for solar farms could otherwise be used for food production. However, solar PV combined with agriculture or "agrivoltaics” is seen as an emerging area of interest.

Issues on energy storage and grid integration have been flagged. Solar energy is intermittent, depending on sunlight, which leads to reliance on energy storage systems such as batteries or backup fossil-fuel-based systems. The sustainability of the batteries used for energy storage, particularly lithium-ion batteries, comes into question due to mining impacts and limited recycling options. Without proper grid integration, the variable nature of solar energy can strain electricity grids, requiring further investment in infrastructure.

There is also the question of environmental justice and equity. The benefits of solar PV are not evenly distributed, with some regions benefiting more than others. Additionally, communities near mining or manufacturing sites may face adverse social and environmental impacts while not benefiting directly from solar energy. Addressing these sustainability concerns will require advances in recycling technology, improvements in manufacturing processes, the development of circular economies for solar materials, and stronger environmental and social regulations in the supply chain.

There is no doubt that solar provides immense potential as a source of clean energy. May be a more sustainable option is through exploiting the solar heat rather than PV. For that matter, even agricultural biomass is produced through solar-powered photosynthesis. But the most promising option is to simulate the energy production of the sun itself. This refers to nuclear fusion which is now the subject of intensive collaborative research by many countries.

* The author is an Associate Fellow at the Ungku Aziz Centre for Development Studies (UAC), Universiti Malaya, and may be reached at uacds@um.edu.my

** This is the personal opinion of the writer or publication and does not necessarily represent the views of Malay Mail.