4 Ways to Manage the Changing GridBack to Top
The grid is experiencing more tension than ever under the weight of increasing power quality requirements and a fundamental shift in how it operates. With an influx of distributed energy resources (DERs), such as wind and solar, the grid now has to control power flowing two ways—and often at fluctuating and unpredictable rates. This poses a challenge for regulating frequency and voltage.
Although it’s difficult to predict how the grid might operate in the years to come, reliability should never be jeopardized as we adjust to change. The best way forward is to mitigate current issues and ensure solutions are flexible so they can adapt to future needs. We can improve reliability in both the short and long term by:
- Measuring and reducing momentary outages. Utilities have had success reducing sustained outages, but in many cases the techniques for reducing them have caused an increase in a different type of outage: momentaries, or blinks. In years past, blinks were not as prevalent, nor did they have major effects. But in today’s digital age, momentaries cause significant issues—and they’ll continue to be less and less tolerated. Yet, many utilities do not measure outages less than a few minutes.
The result? Their reliability metrics improve, but customer complaints go up. Some progressive utilities have implemented strategies and technologies that reduce both sustained and momentary outages. Even after only a short time using these solutions, they’ve seen monetary benefits from momentaries avoided, happier customers, and truer reliability. To achieve this level of reliability, utilities must start tracking momentary outages to understand fully how the grid is performing. Without measuring them, there’s no way to manage the grid as it continues to change.
- Adopting condition-based maintenance strategies. Driven by rate cases that do not include operational maintenance in their base, many utilities have had to rely on a “run-it-’til-it-breaks” mentality with their equipment. They’re beginning to move away from this philosophy, recognizing the importance of vigilant maintenance, especially in the face of the ever-changing grid. For example, a utility might know the temperature of a transformer when it runs at a certain number of amps. But they also might notice that, at the same number of amps, the transformer is hotter than usual. Such comparisons help utilities keep assets in check and in optimal shape to maintain reliability.
- Using microgrids. Microgrids empower locations to disconnect and reconnect to the grid when needed. As a result, microgrids effectively ensure reliability for those customers within their parameters. However, microgrids tend to be complex—and often expensive—solutions. Even when a microgrid operates independently, the utility has to plan for its load when it reconnects, meaning there’s a cost to covering this microgrid-grid relationship, and it’s a cost that’s usually shared among all customers in the utility’s service area. Until clearer rules are created around who will pay for this solution, microgrids will continue being incorporated into the grid, but at a slow rate.
That said, down the line, utilities might be able to use microgrids as a dispatchable load—even to the point of predicting situations when there will be a higher demand, scheduling their microgrid to turn on, and reserving power to give to the rest of the grid. This may help cover costs, motivate microgrid construction, and increase reliability for the wider grid.
- Using energy storage systems. The energy source within an energy storage system is technically a DER, but the system as a whole uniquely acts as a load while charging/storing and as a generation source while discharging. Because it can both absorb and release energy, the system can correct voltage sags and surges, smooth the varying nature of renewable resources, and provide many other benefits that improve reliability. Right now, most customers are using energy storage systems for multiple purposes simultaneously, such as for peak shaving and var support. As more battery chemistries are studied, more leaps will occur in the technologies and new options will emerge in the market. This will continue to drive the cost of batteries down and make energy storage systems a more economically viable solution.
Given how drastically power delivery has transformed recently, it’s urgent that we adapt and plan. The longer we wait, the more quickly we fall behind in providing reliable power and the more customer complaints we’ll receive. Even though the grid continually changes, we must stay accountable for the fact that reliability must only get better.
June 26, 2017