Energy is of vital importance in today's world, but creating sustainable energy sources is even more important for the future sustainability of Earth. When assessing sustainable energy sources, renewables come to mind. But they always come with a warning label. There are those who will always criticise renewables for being inefficient and costly. There is one notable issue with renewables that people always reference - a lack of reliable renewable resources. If the sun doesn't shine or the wind doesn't blow, they are useless (that isn't strictly true as solar can still produce energy with little sunlight). But if you're lucky enough to live in a sunny, windy, hydrologically and geologically active, that tends not to be an issue.
In sunny countries, solar makes an ideal renewable energy. However dust can be an issue as it settles on the surface of PV modules, covering the surface and reducing the amount of solar radiation hitting the surface. This is a real issue for sunny desert countries, but what are the implications? Well I suppose I wouldn't be writing a blog or asking the question if I hadn't found a rather nice recent article that looks at the issue!
Zarei and Abdolzadeh (2016) modelled the thermal and optical impact of dust on solar PV panels. The authors compared and validated their model with literature values. They modelled the amount of "6.44 μm sized mono-disperse dust particles" which withstand average angles of solar PV installation. At a 30° tilted dusty PV cell, Zarei and Abdolzadeh (2016) found the maximum power with 0.224 mg/cm2 of dust (the amount of dust that tends to stick to the module at 30°) is 13.53% lower than a dust-free solar PV cell (figure 1).
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| Figure 1: maximum power output of PV cells at different dust densities (Source) |
This information is very useful, especially in modelling the effectiveness of solar PV cells in dusty countries. Furthermore combined with average local dust or sand sizes, the model can be localised to find the maximum electrical output of dusty solar PVs. Finally, in national and international energy models, this information is vital for recreating realistic and accurate understandings of renewable energy production.
Resources are vital, but our over reliance on energy is incredible. For a sustainable future, we need to rely on clean and un-exploited sources of fuel. These small studies can help our fuller understanding of global energy consumption and potentially calculate and reduce the impact of climate change!
Happy New Year Louis!
ReplyDeleteInteresting post, I think it's great to read a balanced perspective of renewable energy instead of one that highlights it as the world's safest and only future option. The fact that reliable renewable energy - particularly solar & thermal - is globally uneven is something that I've also been researching for my own blog. The issue with dust in desert countries effecting the efficiency of solar PV cells is something that I have come across nor considered myself, however it makes total sense. I wonder, how is this issue overcome? Do you have to clean the solar panels, or is it simply a case that they aren't suited to the climate full-stop?
Happy New Year Caitlin!
DeleteThanks, I think this is an issue that cannot necessarily be overcome, as the dust will collect regardless. However, it needs to be considered when modelling electrical production from renewables. The reduction in efficiency is 13.53%, so even when dusty, they are suitable, the issues just need to be considered.
This was a very amusing read! I find it mind boggling that something as technical as solar energy can be stopped by dust... do you know if this is really a problem in the UK for solar energy?
ReplyDeleteIn the UK, the issue is generally the lack of solar energy. Although (and this is rather rare and genreally short lived) snow can have a similar impact on solar PV and solar thermal panels. I imagine this would be in a similar way to dust, although I don't know unfortunately. The main difference between snow and dust is that snow could let light through, whereas dust tends to block all dust (http://www.theecoexperts.co.uk/does-snow-affect-output-solar-panels). As for dust, I feel that isn't a significant problem...!
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