While we know that higher temperatures cause a surge in electricity demand, the impact of climate change on electricity generation, transmission and distribution systems is also an area of increasing concern, one that has not been duly acknowledged or addressed yet.
South Asia, where temperatures are on the higher side in general, has been experiencing blistering heat waves for some years now. In 2015, the severe heat wave that struck Southern Pakistan had temperatures as high as 49 °C. And this was not an isolated incident. It followed a separate heat wave in neighbouring India that was the deadliest since 1979. Bangladesh too is experiencing annual heat waves, with temperatures already peaking at close to 40 °C in April 2017. The same is true for countries such as Australia and the United States where peak temperatures are increasing causing heat strokes, dehydration and hyperthermia among citizens.
Qamar-uz-Zaman Chaudhry, author of Pakistan’s climate change policy, in 2013, showed that the number of heat waves in Pakistan had increased from 1980 to 2009 and in 2010, the peak temperature at Mohenjo-Daro, reached 53.5C the 4th highest ever recorded temperature in Asia. Shahbaz Mehmood, a climate scientist at the Global Change Impact Study Centre in Islamabad says, “due to global warming, probability of extreme events’ occurrence has increased in Pakistan. If we look at the frequency and the trend of the extreme weather events impacting Pakistan then it is easy to find its link with climate change.
Urban cities such Karachi are more susceptible to heat waves due to “heat island effect” which causes temperatures to be 5-8 °C higher vs. the countryside. Deforestation, miles of asphalt roads and vertical building structures increase heat absorption and limit air circulation. Compound this with increased vehicular and industrial emissions. And then add the increased energy consumption of an unchecked growing population in poorly planned yet densely populated settlements.
In fact, energy demand and supply are both inextricably linked to climate change. While we know that higher temperatures cause a surge in electricity demand, the impact of climate change on electricity generation, transmission and distribution systems is also an area of increasing concern, one that has not been duly acknowledged or addressed yet. Researchers have linked reduced water supplies arising from drought and rising temperatures to nearly a 30% decrease in electricity production for nearly 98% of the world’s power plants. The distribution system is also vulnerable. Extreme heat waves prevent transformers from dissipating heat efficiently and can short-circuit them causing black-outs, one reason we see the number of faults and trips go up during summers. Higher AC usage during heat waves heats wires considerably, making them expand. When they expand, they sag, and are more likely to short-circuit and knock out power. When other lines pick up the burden, they too, become overloaded. Extreme temperatures also cause electrical equipment to develop cracks from thermal expansion and contraction, damaging the equipment and making it unable to sustain high electricity demands. Bottom line is that when energy demand is the highest, likelihood of power breakdowns is the highest.
The heat waves show no signs of abating, in fact we can expect longer, more intense and more frequent such events in future unless as a society we can take ownership of this issue and work together to combat it. Improved energy efficiency and conservation is the fastest and cheapest way to meet electricity needs while saving consumers money on their energy bills and reducing carbon emissions thereby containing the cycle of global warming. On an individual level, consumers need to make choices for the greater collective good such as setting ACs above 26 °C to avoid over-loading the system and causing blackouts for the whole population. On an administrative level, renewable sources of electricity generation, particularly wind and solar energy should be added to the generation mix; materials with cooling properties should be utilised for buildings, trees plantation, and creation of green spaces and water bodies such as fountains to absorb heat, and maximising prevailing breeze paths should be emphasised. Without collective efforts, combatting climate change is not sustainable.
