Environment Focus:

Expat Living contributor CATHIE HEARNS sheds some light on solar, the world’s third biggest renewable power source behind water and wind.

Does solar have a dirty secret?

One year’s worth of solar energy hitting the earth’s surface exceeds the potential of all the known energy reserves for oil, coal, natural gas and uranium. In just one hour, the solar energy reaching the earth’s surface is around 173,000 TWh (terawatt hours, or one trillion watts). This compares to humanity’s annual consumption of 160,000 TWh (in 2017).

So capturing the sun’s energy to power our lives seems the most obvious and cleanest way forward. Right? Unfortunately, it’s not quite that simple.

Analysing the industry

In order to gauge the carbon footprint of a product, you need to carry out a Life Cycle Analysis (LCA). This should take into account everything involved in the realisation of the product from “cradle to grave” – for example, the mining of raw materials, the transportation of those materials and the finished goods, the electricity and other resources used in the manufacturing process, the cost of deployment, and so on.

With solar technology evolving rapidly over the last 10 years and specific production methods varying hugely from country to country, it’s difficult to put an exact figure on the industry’s greenhouse gas emissions.

What’s also hard to put a price on are the “externalised costs”. Simply put, these are costs generated in the life cycle of a product that are carried by society as a whole; for example, the damage to human health caused by improper disposal of toxic by-products. Not taking these costs into account can result in a corporation gaining higher profits while humanity and the environment pay the price of impaired health or polluted landscapes.

The problem of panels

This is indeed an issue of grave concern in renewable energy’s poster child. At present, there is very little regulation in place to ensure solar panels are safely disposed of or recycled at the end of their 25-to-30year life span. Panels contain lead, cadmium and other toxic chemicals that have huge polluting potential if allowed to leach into the soil; and this is exactly what is happening, as the majority of them are ending up in landfills. Some are also being “recycled” by being sold to developing countries; those countries are happy to receive cheap yet less efficient equipment, but they’re poorly equipped to deal with them responsibly at the end of their life cycle.

The International Renewable Energy Agency (IRENA) estimated that in 2016 there were about 250,000 metric tonnes of solar panel waste in the world. This, they say, could grow to 78 million metric tonnes by 2050. It’s not a problem that’s going away. However, the good news in Singapore is that the use of solar energy is in its infancy and the de-commissioning plan is already being addressed.

Weighing up the positives

Let’s not lose sight of the big picture, though. Solar panels may consume a lot of electricity, glass, heavy metals and rare earth elements in their manufacturing process compared to other energy sources, but on average it’s calculated that the panels pay back that carbon debt in less than two years of use. In other words, their lifetime carbon emissions are way, way lower than that of fossil fuel energy.

At the moment, this huge benefit comes at a price. The lack of forward planning by the industry itself and the governments that have incentivised it – and therefore should be regulating it – does leave a rather bitter taste in the mouth. And, with the price of solar panels dropping by up to 90 percent in the last 10 years, one can’t help but wonder about that issue of externalised costs…