Even if US President Trump does not want to acknowledge climate change, global warming has long been felt in the US as well. Heat waves and forest fires are already piling up in many parts of the country, and average temperatures have risen measurably in the US as elsewhere. The US is also one of the areas of the world where temperatures are rising faster than the global average. According to current forecasts, the two-degree limit of US warming will be reached by 2030, ten years earlier than the global average. Summer heat waves and extreme temperatures will increase more in the US than in many other regions. In just a few decades, record summer could become the rule, especially on the US East Coast, but also in the west of the country.
In this context, Maximilian Auffhammer from the University of California at Berkeley and his colleagues have now taken a closer look at the impact of the upcoming climate change on the US electricity grid. "It is estimated that the climate impact on the electricity sector by the end of the century will be responsible for the majority of global economic damage, " the researchers say. Because especially the increasing heat days in the summer drive the power consumption for air conditioners and other cooling devices in the height. How intensively this will be felt in the US and whether the US electricity grid will meet this demand, the scientists have now investigated. To do so, they first analyzed the peak load and average power consumption in 166 zones and more than 2, 800 US counties in terms of prevailing daily weather. As the researchers report, this resulted in a nearly linear relationship above 21 degrees Celsius: the warmer a day is, the more the peak load and average power consumption increase. This applies almost to all regions of the US, said Auffhammer and his colleagues. The next step was to translate that relationship into predictive models that simulated two climate scenarios used by the IPCC, RCP4.5 and RCP8.5.
Up to 18 percent higher load peaks
The result: In both cases, increasingly hot days are causing an increased load on the US electricity grid. Above all, the peak loads rise significantly more than previously thought, as the researchers report: In the moderate warming scenario, the daily peak loads at the end of this century would be seven percent higher than today. In the business-as-usual scenario, peaks in peak load even increased by 18 percent. Although it could even come to a slight decline in average electricity consumption in the northwest, because in winter there will be less electricity needed for heating in the future. However, this effect is not sufficient to compensate for the overall higher consumption and above all the peak loads on hot summer days, as the scientists explain.
On the US electricity companies this comes to a lot of costs. Because if the power grid is to cope with the additional burdens in future, then investments are indispensable, the researchers said. They estimate that installing an additional seven percent capacity in the US network would cost around $ 70 billion. If one assumes that the peak values of the consumption increase by up to 18 per cent, then the costs would be even with 180 billion US dollar. "This means that the values found so far in the literature substantially underestimate the true costs of the electricity sector, " say Auffhammer and his colleagues. In addition, these calculations do not take into account any increase in electricity consumption due to the growth of the population and the economy. "This suggests that our estimates are even far too low, " the scientists emphasize. In their view, action must be taken - on the one hand through climate protection and possibly new technologies for electricity storage and through adaptation and upgrading of electricity grids. display
- Maximilian Auffhammer (University of California, Berkeley) et al., Proceedings of the National Academy of Sciences, doi: 10.1073 / pnas.1613193114