In August, we asked customers to conserve energy – here’s why

On August 18 and 19, we asked you to conserve energy during the time of day when demand is the highest: 3 p.m. - 8 p.m. That’s typical weekday behavior for most of our customers who are on time-of-use service plans, such as Saver Choice, but not as familiar to those on our standards plans, who pay the same amount for energy all day.

Why did we make the call to conserve? Simply put: supply and demand. Weather drove up regional demand for energy to levels that met – and in some cases, exceeded – supply. The western United States was in the midst of a regional heat wave, driving excessive heat warnings in 12 states. That heat strained regional energy markets, especially in areas where such temperatures are not the norm.

During that week of intense heat in the West, several utilities and system operators across the region declared energy emergencies – from Public Service Company of New Mexico to the California Independent System Operator to Salt River Project here in Arizona. There was not enough energy in the regional market to make up for shortfalls – whether due to unexpected conditions, such as a wildfire, or inadequate planning.

Far away view of a Phoenix freeway with sunset
APS never reached emergency status. As a local utility in Arizona, we know what it takes to prepare for the heat. After all, summer is our season, and our employees work year-round to be ready to deliver reliable power during the hottest days of the year. In fact, we plan for a 15% reserve margin, a cushion of more power than we think our customers will need. That margin gives us more ability to handle the unexpected and to serve residents and businesses throughout the state when they need it most.

In addition, our time-of-use service plans are designed with supply and demand in mind. On-peak prices are higher because that is when energy is in larger demand, but tighter supply. The plans send you a price signal to conserve at the most critical hours – saving on your bill if you shift energy use to other times when it’s cheaper – and helping the whole system stay in balance.

So, if APS was never in an emergency situation, why did we ask you to conserve power on such hot days? We made that request out of an abundance of caution to ensure we’d have enough power to manage the unexpected, given so many of our usual back-up resources in the region were heavily strained. And you came through, with an up to 3% reduction in energy demand on our system due to your voluntary conservation during the critical hours of those days.

We never ran short of resources to meet customer needs even when California utilities were forced to impose rolling blackouts. Indeed, outside of critical peak times, we were able to support our utility partners in the region by selling them our excess energy (but only when our own customers did not need that energy). Every dollar from these sales is passed directly back to customers through our Power Supply Adjustor line on your bill.

Please know that we don’t ask you to conserve energy unless reliable service for our customers is at risk due to extreme conditions. It’s not a request that we take lightly. In fact, this August was the first time in 16 years that we called for voluntary energy conservation. It’s definitely out of the ordinary, and we appreciate the response from our customers. Your actions made a difference!

Rest assured that we are carefully planning and running our operations based on your energy needs. We are dedicated to providing affordable and reliable service to our customers – no matter the weather.

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