A rare winter snow storm and a multiple-day stretch of frigid temperatures have crippled the electrical grid in Texas. There are many reasons for these problems.
The electrical grid in the United States consists of three large areas called interconnects. Two of them cover the vast majority of the US. The Eastern Interconnect lies east of the Rockies, and the Western Interconnect lies west. These regions are home to numerous electrical utilities that generate electric power at coal, nuclear, natural gas, wind, and solar facilities and transmit it over several hundreds of miles of overhead and underground cables to areas where the power is consumed
Utilities in these interconnects work together as balancing authorities, striving always to balance generation with load. To do this, they rely on each other to exchange power. When one utility has a surplus of generated power, it can sell it to those who have a deficit. Utilities in these interconnects work with each other to keep the lights on.
The third interconnect, interestingly, is Texas. Indeed, the United States electrical grid is divided up into the Eastern Interconnect, the Western Interconnect, and the standalone grid of the State of Texas. In 1935, in order to avoid new regulations on electrical generation brought on by the Federal Power Act, Texas utilities agreed not to sell power outside of state lines. Over the years, as utilities in the other two interconnects built transmission lines to connect each other in a redundant web, Texas, without an external power market, remained relatively isolated, a self-sufficient electrical enclave, able to share no more than about 800MW total with its US neighbors. Although that is enough power to serve the needs of about 800,000 homes, it comes in well below the state’s current electricity shortfall.
The US grid is designed to be resilient. When transmission lines are knocked out by a storm or other natural disaster, when fuel shortages or mechanical failures shut down a generating facility, or even when ice weighs a transmission line into underlying brush that ends up shorting it out, the grid is designed to call up additional intra-utility generation and, if necessary, call upon generators in other utilities and states to ramp up their output to help meet the interrupted demand.
As an electrical quasi-island, Texas doesn’t have nearly that level of flexibility. So, when un-insulated power plants’ fuel-carrying pipes froze and when transmission lines sagged into short-circuiting ground cover under the weight of winter’s frost, power became scarce. When people turned up their electric heaters to cope with the cold, they exacerbated the shortage. It is a problem of limited supply and magnified demand.
This is likely not going to be an isolated occurrence. As the climate continues to change, all electrical grids will face conditions for which they were not originally designed. To confront this new reality, utilities will need to pursue some combination of building new transmission lines (including additional connections between Texas and the other interconnects), hardening existing facilities against more adverse conditions, and deploying more distributed, local generation, mostly in the form of non-polluting renewables to avoid endangering the health of nearby residents.
These solutions will not be cheap, but neither has been the price of Texas’s current crisis. This is just an opening blow. The US electrical grid must take bold steps now to continue operating reliably and efficiently in a changing climate.