What is causing the rolling blackouts?
As Arkansas’ representative on the National Conference of State Legislatures – Energy Supply Task Force, I want to go over why we are seeing the need for rolling blackouts amid this unprecedented cold snap. You may remember a similar situation happened in the north east a few winters ago and this summer California had brown outs due to the extreme heat.
It used to be that a power utility had to build enough generation to meet its highest peak demand. These peak demand days only occurred a few times a year typically on hot summer days when everyone is running A/C. This meant everyone paid higher electric bills for the construction and maintenance of these rarely used resources.
That started to change during WWII, when here in Arkansas the local utility could not keep up with the power demands for aluminum production used in the war effort. To combat the problem local utilities teamed up. After the war they saw the benefits and Southwest Power Pool was born, HQ in Little Rock, which covers western Arkansas. Central and Eastern Arkansas are in MISO. Both of these interconnects have territories covering several states. Texas is in ERCOT and is isolated from all other states.
The idea for these interconnects is simple, when we’re having a hot summer, we can buy the excess capacity from the northern states. When they’re having a cold winter, we can sell them ours. This creates redundancy in the grid and saves the cost of building and maintaining generation resources that are used only one or two days a year.
The widespread nature of the arctic air, however, means everyone is seeing an increase in peak demand and there are few / no areas within the interconnected area that has excess capacity to make up for it.
The main issue, especially in Texas, is increasing competition for natural gas. Over the past few years utilities have increasingly switched to natural gas for generation. With this cold snap, homes and businesses which heat with natural gas are driving up demand, creating a supply problem for natural gas power plants. In the past, coal power plants could store a month or more supply on site and thus they were protected from temporary supply disruptions. It is not possible / practical to store that much natural gas.
Natural Gas utilities have called on their customers to reduce demand to help.
Wind and Solar both have their place, but are likewise impacted by cold snaps. Ironically solar panels become more efficient in colder weather, however if they become snow covered or are under cloudy skies their production drops and, of course, it stops altogether at night.
About 10% of the capacity loss in Texas came from iced up wind generators. While they can be hardened against frigid temperatures, ice forming on the blades reduces their efficiency and can result in ice chunks being thrown and damaging the towers. There is also no guarantee there will be wind to operate the turbines. The regional interconnects typically compensate for the variable nature of these resources very well – i.e. its cloudy in one area, but clear in another. This is so wide spread, it is making that difficult.
Besides our dwindling coal power plant resources, the most reliable power source during these extreme cold snaps is nuclear. They are not susceptible to supply disruptions, as they are typically only refueled once every two years. They produce a lot of power (almost half of our power in central Arkansas comes from Nuclear One) and they operate 24/7 regardless of the weather.
Looking to the future. With increasing reliance on the intermittent nature of renewable energies, it is important we also have reliable base load generation that is hardened against supply disruptions. When the Uranium pellets are removed from nuclear reactors, they still have about 95-98% of their potential energy. Research has been on going and is coming to maturity for small scale and modular nuclear reactors, which could use this fuel. Instead of one large nuclear plant, these would be smaller, cheaper, and safer city scale projects. These decentralized resources would bring resiliency to the grid and help prevent the blackouts we’ve seen across the country.
In a few days, the weather will warm and we’ll be back to normal. There will be investigations into what happened and how we can take steps to be better prepared for the next time.
