Puget Sound Energy residential demand response and VPP economics

Puget Sound Energy (PSE) is Washington’s largest utility, serving about 1.2 million electric customers from Bellingham to Olympia, including Bellevue, Redmond, Kirkland and much of King County outside Seattle. Its demand response portfolio, branded PSE Flex, delivered about 87 MW in winter 2024–25, above its 86 MW goal, from more than 620,000 customers across eight programs, according to Clearing Up. Almost all of it is simple demand response called a few dozen times a year. By April 2026, Flex Smart had about 40,400 customers, Flex EV 10,800, Flex Water Heaters 422 and Flex Batteries about 800, according to PSE’s 2026 demand response request for proposals.

That is starting to change. Washington’s 2024 law for large combination utilities requires PSE to hold a load-flexibility portfolio equal to 10% of peak from 2030, and the region’s load is growing: EVs, heat pumps and, in PSE’s own large-load queue, data centers and tech campuses. Unlike Oregon or New York, Washington has no separate state agency paying upfront storage incentives; PSE pays the equipment rebates, the enrollment money and the event pay. Uplight runs the residential Flex programs for PSE.

The rate is the bigger lever for everything except the battery. Moving 3,500 kWh of EV charging to Schedule 327’s super off-peak saves about $299 a year against the standard rate’s upper tier. Heating a heat pump water heater before 7 a.m. and letting it coast through the peaks adds about $150, and preheating with the heat pump before winter peaks about $77. Flex pay for the same equipment is $20 to $50 a year.

The catch is the rest of the house. PSE’s own example of an 800 kWh month puts about 17% of use in the peaks, according to its price summary. Without any shifting, that home pays about $64 a year more on Schedule 327 than on Schedule 7. Time-of-use pays only when flexible loads actually move, and PSE does not guarantee savings.

The programs and the rate do not all combine. Time-of-use customers can also join Flex Smart or Flex Rewards, according to PSE’s time-of-use FAQ, but they cannot take the Flex EV incentive, according to PSE’s charging page. PSE does not say whether Flex Water Heaters combines with time-of-use, so we leave it out of the time-of-use home. Schedule 327 may be full; Schedule 307 has the same peaks without the super off-peak price, and would save the EV about $185 a year instead.

Why the battery pays only modestly. Flex Batteries pays for energy, not capacity. At $0.50 per kWh, a 13.5 kWh battery earns about $5 per two-hour event, and it takes around 100 events to reach the $500 cap. Energy the battery exports in an event is credited like solar exports, and recharging costs about $0.14 per event, according to PSE, so the bill effect is small either way. The pay is taxable income. Massachusetts’ ConnectedSolutions, by comparison, pays for each kW held through a summer of events, several times as much for the same battery.

Stacking needs care, depending on M&V methodology. Flex Batteries pays per kWh measured at the battery, so it would stack cleanly with daily time-of-use cycling if PSE allowed it. Flex EV pays per kWh reduced during events, which is close to nothing for an EV that already charges overnight. Flex Rewards and Peak Time Savings pay against a whole-home baseline and cannot be combined with the device programs.

Consider a hypothetical all-electric home in Bellevue with a ducted heat pump on a smart thermostat, a heat pump water heater and an EV driven 12,000 miles a year on a Level 2 charger. Over 10 years, Schedule 327 with Flex Smart is worth about $6,400, including $1,375 of equipment rebates. Staying on the standard rate and enrolling all three devices in Flex programs is worth about $2,600.

Adding a battery to the standard-rate home brings the total to about $6,600, but the battery alone costs about $15,970, and the home cannot move to time-of-use while the battery is enrolled. Only an enhanced incentive is large enough to change that picture. Our Residential VPP Calculator runs the program side of this for other equipment and ZIP codes.

A battery is the only flexible device in the home that costs more than a few thousand dollars, so it gets its own capital stack. For a home already saving on time-of-use, the comparison is worse than it looks below: the battery’s $297 a year of Flex pay would replace about $462 of time-of-use savings.

The standard path covers about 25% of the battery’s cost in 10 years. Pathway B, for households with reliability concerns in specific grid areas, raises that to about 56%, and Pathway A, for income-qualified households, those on PSE’s Bill Discount Program or with a registered medical device, to about 87%. Opening time-of-use to battery customers would roughly double the standard path’s coverage without any new incentive spending.

PSE runs one Flex brand with a program for each kind of equipment, under Schedule 272. A household can combine the device programs, or choose a behavioral program on its own, and the rate it picks decides which combinations are open.

The thermostat, water heater and charger are small purchases that rebates largely cover. The battery is the one that needs financing. Each path below ends with the household owning the battery, so the 10-year totals compare like with like. The lease has no money down and a low monthly payment, because the leasing company claims the 30% federal credit. The household still pays a buyout of about $3,190 at the end of the term. With only Flex pay coming in, every path is cash-negative over 10 years; the question is how much backup power is worth.

PSE’s simple demand response works: it beat its 2024–25 goal. But getting from roughly 129 MW to about 500 MW by 2030, while large loads grow, will take resources PSE can dispatch for hours, in winter mornings and evenings, with predictable performance. PSE set out in 2023 to build a 100 MW virtual power plant with AutoGrid, according to Utility Dive, and its 2026 demand response request for proposals asks vendors for turnkey programs.

Related: the hosted battery money trail, the Portland General Electric residential deep dive for Oregon, the Eversource residential deep dive for a capacity-paying program and the Puget Sound Energy C&I deep dive.