Solar energy and other renewables are often brought up as possible solutions to the scary advance of global warming. What is often disregarded is the other side of the coin: what impact will global warming have on solar energy? With temperatures rising all over the world, one would intuitively believe that impact to be positive, but scientists’ predictions are not so straightforward.
According to a study conducted in 2011, effects of global warming on solar energy will vary depending on location and the type of solar panels. Both traditional solar panels and and concentrated solar power plants (CSP) - which use a system of mirrors instead of semiconductors - will see their efficiency increase, but in different ways. Taking the example of Germany, the current European solar energy leader, predictions saw photovoltaic panels gain around 3% efficiency, while solar farms would go up by 10% by 2080. The UK would also benefit from higher temperatures, but in smaller percentages.
Interestingly, not all areas would be positively affected by the extra sun. In places like South-West US and the Middle East, solar efficiency would decrease by 4-6% both in the case of solar PV and CSP. Photovoltaic panels will have it worse than CSP farms on average, with most areas seeing a decrease in potential. That is because PV panels work best in cool temperatures, while CSP harnesses heat and would therefore benefit from higher temperatures. However it must be noted that these small relative variations would not change the fact that solar panels installed in North Africa would produce more energy than those in the UK.
Even though these studies seem to point to a silver lining, global warming will have other negative consequences on solar energy. Concentrated solar thermal plants may benefit from higher temperatures, but drier climates will only increase the already high demand for water to cool the systems. Dry-cooling technology also becomes less effective as temperatures rise. With this trade-off in mind, and given the predicted increase in potential, research and investment should focus on making solar power more efficient.
Arguments Against Solar Energy
Solar energy remains one of the best options to substantially reduce CO2 emissions. While some argue that there are emissions associated with the production cycle of solar panels, they are much lower compared to lifecycle emissions for coal and natural gas. Additionally, both of these energy sources continue releasing carbon dioxide while they produce electricity. Solar panels, on the other hand, produce completely green energy with zero emissions once they are installed.
Another argument moved against the sustainability of solar panels is that the materials used to manufacture them are toxic to the environment. While it is true that mishandling these materials might pose a threat, it is also a fact that they are very rare and valuable, which gives an incentive to manufacturers to recycle as much as possible.
One last potential disadvantage of solar plants in particular, which according to the study should receive special interest, is that they occupy large portions of land. Unfortunately that land can’t be shared with agricultural farms, which is a possibility in the case of wind power. The obvious solution to that is to use “low-quality” land that cannot accommodate agriculture. This is an issue that does not concern domestic solar panel installations, since they exploit unused roof space. Moreover, scientists are working on more ways to exploit asphalted areas such as roads to avoid the land-wasting issue.
Read more: Solar Panel Myths