The world is increasingly beset by severe weather events: heat waves, hurricanes, wildfires. Overall extreme events are impacting on power supply and distribution networks. Utilities are having to plan extensively about how to maintain electricity during emergencies.
One important aspect of this is ensuring that the utility can install a flexible demand response system ahead of any crisis, which can ensure a rapid load-management intervention. This can free up valuable resources for utilities, allowing them to shift those resources to other areas during large scale disasters. This article looks at three challenges in these circumstances and how to mitigate any disruption.
Responding to Localized Grid Damage
Severe weather usually harms the most vulnerable components of the grid: poles, lines and transformers. Customer loads need to be modulated to match reduced grid capacity until power can be rerouted or distribution assets can be repaired or replaced. This requires information about the entire grid and input from sensors located throughout.
Geographic grouping of demand response resources (at the substation level or other grid sections) can enable faster dispatch of these resources when grid assets are damaged. It’s important to have planned for how much load each group can reliably shed under various conditions. Then grouped resources can be matched to the need for power in other grid sections. This can help prevent outages from spreading and reduce overall grid stress to speed recovery as repair crews restore damaged plant and equipment.
Throttling Demand To Counter Supply Shortages
When generation or transmission gets knocked down, judiciously distributing the remaining power on the grid can help keep customers safe until new power supply can be brought online. This involves more widespread load-management strategies across larger areas. This is often the case during serious weather events, or in Texas in February 2021, when large elements of the system went down. When the whole power system is running short on supply, that’s when you want to dispatch from the entire demand response program. Grid operators also usually find it most effective when the reduced load is consistent across the entire duration of the event.
Load Management During Extended Emergencies
Severe weather, large wildfires or the effects of other disasters can last for weeks in the worst case scenarios. Staggering individual loads within the aggregation block can help ensure that no one customer’s energy use is curtailed for too long. Good planning is important to prevent particular sectors of consumers being without power for significant periods. By preparing a disaster plan, plus the utilities knowledge of the thermodynamics of residential and commercial users and advanced technology such as AI and machine learning utilities can create dynamically updated profiles that shift load reduction periods across the customer base. Dynamic staggering allows utilities to deliver consistent load for longer periods, without impacting comfort for any individual customer too much. With intelligent demand response, management can distribute load contribution across the service territory in a way that maximizes available capacity.
Conclusion
Business and residential load types are evolving, creating new opportunities for load management during grid emergencies. There is the new demand response potential of EV charging and its potential contribution could be significant. Any large load that can be scheduled should be a prime target for demand response programs, for both economic and reliability reasons. Where smart meters or other temporally-resolved sensors are deployed, demand response can be more nuanced and predictive. Aggregating lots of individual loads and distributed energy resources to create a coherent, flexible resource is challenging, for utility companies. If they have enough good data from grid endpoints, and intelligent software, it is possible to create a MW-scale flexible resource out of hundreds to thousands of devices. This will ensure that if a major event happens, there will be enough flexibility to reach a positive outcome in a short period of time.