The prominent Scottish comedian, Arnold Brown, is known for humorously commenting on the central importance of “timing” in the comedy profession: “If the audience turns up on Tuesday and you turn up on Wednesday…that’s bad timing.”
Little did the Scottish funnyman know, that his wry words of wisdom are also acutely relevant to the modern power grid — wherein electricity must literally be produced at the same instant it is consumed, requiring constant balancing of supply and demand.
Any deviation from precisely balanced second-by-second timing, and the electric grid starts to come undone, descending into operational instability and blackouts. Even a comedian can tell you that’s not a funny situation.
In recent years, the “timing” issue has emerged as a defining challenge for the future of utility industry — largely because of the imminent and sizable addition of renewable electricity sources (e.g. sun and wind), which produce power at very specific times of day.
As an example, consider the below chart, which in recent months has become a hot topic among utility experts – in part because it offers a highly interesting scenario, and in part because it looks uncannily like a duck. Each line in the “duck chart”, one drawn for each year between 2013-2020, portrays the hourly amount of non-renewable electricity generation (i.e. electricity production from fossil fuel power plants) that is projected to be needed in California over the course of a particular March day.
The “duck chart” suggests that California’s substantial growth in renewable energy will necessitate changes to the timing of conventional power production as well as power demand (Source: CA-ISO)
Why does the chart look like a duck? Its distinctive shape stems from California’s ambitious goal to obtain 1/3 of its electricity from renewable sources by 2020, and the associated expectation that the need for non-renewable electricity generation will decline significantly during the sun-drenched daytime (the “belly” of the duck).
The evening, however, is a different story: when the sun goes down and people start returning home to commence their early-to-mid evening energy usage (especially in an early sunset month like March), conventional power plants may have to ramp up very rapidly (indicated by the steep “neck” of the duck), to compensate for the sun’s disappearance. Unfortunately, it is notoriously difficult for conventional power plants to ramp up their output so quickly — especially in the case of the duck scenario, which calls for a near doubling of output within a few short hours.
Although the duck chart presents the results of a particular modeling exercise, and shouldn’t be treated as an immutable forecast, it emphasizes a critical “timing” question confronted by the 21st century power system: in a future of more renewable energy, how can utility companies and grid operators help align electricity demand with the times of day when renewable electricity production is most available?
Instructive examples of how to coordinate the timing of electricity demand and supply can already be found across the utility sector. The most familiar of these examples springs into action every summer – when skyrocketing electric demand for air-conditioning often threatens to outstrip the generation capacity of power plants. In response to this “peak demand” challenge, the power sector has become adept at re-calibrating itself by firing up additional power supply and also, increasingly, by helping customers reduce electricity demand during the hottest hours of the day — whether through personalized advice, direct load control, incentives, or all of the above.
Another recent example of a utility tackling the timing issue can be found in the Texas renewable energy market, where wind turbines spin most fiercely at night — during the same time, luck would have it, when everyone is asleep and electricity demand is at a minimum. If only the wind could supply power during the same time when utility customers want it! One Texan energy supplier, TXU, is trying to achieve precisely that — by offering free electricity to customers between 10pm-6am (ideal for electric vehicle charging and other automated electricity uses), as a way to promote nighttime usage and smooth out power supply operations.
Notably, the above examples of utilities working to align electricity demand and supply both point to a significant role for the engagement of utility customers, whose energy usage behavior represents an important collective resource to manage the demand side of the power grid’s timing equation. Along these lines, Opower’s new Behavioral Demand Response platform offers utilities a promising strategy to motivate large-scale shifts of power demand to times of day that are more in sync with the electric grid’s evolving power supply profile.
As renewable energy continues to grow worldwide and the “duck chart” continues to quack, stay tuned for news and updates on how utility stakeholders are creatively tackling the “timing” challenges of the 21st century electric grid.