Dusty PV

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).

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!

Exploitation of niches

Arguably one of nature's best exploiters of resources (other than humans) are plants. Especially the invasive ones! They manage to sneak into the open niches of habitats, dominate native plants and exploit their resources...

Okay, that's a little dramatic. But it is a prevalent and note worthy issue that should be discussed.

Dlugosch (et al., 2015) recently summarised this form of exploitation nicely: "non-native plants" "often benefit from low competition for limiting resources that define niches". Dlugosch and her team's research question is to understand if an invading species, which tends to be larger in size than other native plants, is larger due to being invasive or larger due to being able to exploit a niche in the environment. The subsequent article explains the results succinctly and summarises than the availability of resources tends to be the key aspect involved. 

We limit the idea of 'invasive species' and "low competition for limiting resources" to plants and small organisms. An interesting distinction is made which almost creates a 'researcher and them' perception of the world. 

The initial idea for this blog was to look at all kinds of exploitation. However, looking back to my first sentence, I already identify the biggest exploiters and who the biggest culprits are of exploitation.

Maybe we should focus on ourselves? Source

Exploitation can be justified, and is justified by society. It is viewed as a necessity of life, culture and economies. The damage is widespread and the issues are prevalent. As a society, our exploitation is fuelled carbon. So let's see how that impacts the world!