Coal Power Plants Failed Again and Again and Again…
Yet You Are Blaming Renewables for Making the Grid Vulnerable?!
After the recent rolling blackout events on 13 May and 17 May in Taiwan some energy transition skeptics have been trying to connect these incidents with the growing amount of renewable energy on the grid. Some even suggest we need to start limiting permissions of VRE projects getting on the grid. Like seriously, the maximum instantaneous wind-water-solar share on the Taiwanese public grid has not exceeded 20% yet, and we should start worrying about too much renewable energy? Give me a break.
The rolling blackout on 13 May was caused by a transmission substation failure, which led to a trip of the nearby coal and gas power plant station. This immediately resulted in a loss of 2.2 GW of power. With no sufficiently fast frequency response, a unit in another gas power plant tripped, leading to an additional 0.6 GW loss of power. One wonders if such an undesired event could have been avoided or at least mitigated, had there been enough fast frequency response resources, such as batteries, upward flexible VRE, fast demand response, etc…
It can be argued that the system operation afterwards (around 15:00 to 18:00) was overly conservative, such that some portions of the rolling blackouts were unnecessary. But solar power plants actually mitigated the scale of rolling blackouts; were there no solar on the grid in the afternoon and the system operator still operated as conservative as it did, then more household would have to lose power during those 3 hours.
The rolling blackout on 17 May gives yet a better case for building more renewables rather than restricting them. A coal unit in the same coal and gas power plant that caused the rolling blackout on 13 May failed again at noon. This time pump storage power stations kicked in and avoided blackouts initially. Still after 8 hours of operation the energy stored in those power stations ran out, and a rolling blackout for 1 hour was not able to be avoided. Had there been more solar or wind on the grid, such that the pump storage power stations did not have to start discharging so early in the afternoon, the incident could have been completely avoided.
Either 13 May or 17 May, the rolling blackouts pointed to an urgent need for a more modern power grid — one that will be more renewable, more flexible, and more resilient. Any suggestions pointing to the opposite direction is not only hampering the sustainability goals but also endangering the system reliability of Taiwan.
A week later in Australia, as a coal power plant failed spectacularly, causing a contingency on the grid, the same drama seemed to repeat again. It seems wherever a power outage takes place, renewables are always the ones that face the uttermost scrutiny. And this is when the grid only has no more than 10% (in Taiwan) to 30% (in Australia) of renewables!
In spite of all of this, I am beginning to see things in a more cautiously optimistic way. Afterall, there is no way that the world can turn back to the old days, when coal is king and wind / solar are just load prediction errors. The power system improvements after the blackouts in South Australia in 2016 and California in 2020 have shown us what the real solution to power system reliability is. These naysayers can either move on like everybody else, or simply be left behind in the history like those unreliable “baseload” coal power plants.
