Distributed Energy Resources

Snohomish PUD solar project includes low-income set aside

The Snohomish County Public Utility District began signing up subscribers April 22 for its community solar program in Arlington, Wash., and is already close to selling out units.

So far, customers have reserved 5,613 solar energy units. Each unit represents one-fifth of a solar panel and costs $120. A single customer cannot buy more than 130 solar energy units. There is a total of 8,100 solar energy units in the 500-kW solar farm, which has 1,620 solar panels.

About 14 customers have put in requests for the maximum number of units. The average reservation so far is for 18 solar energy units, or about four solar panels. Ten percent of the solar energy units, or 810 units, have been set aside for low income customers.

Not counting the solar energy units set aside for low income customers, there are about 1,677 solar energy units left to sell. They will probably be sold out by the end of the month, Snohomish spokesman Aaron Swaney said.

Snohomish PUD has not yet decided how it is going to offer the 810 units to low income customers. One possibility is a business could buy the units and provide them to low income customers for free. “We are trying to figure out a way that can really make an impact on low income customers’ bills,” Swaney said.

Snohomish PUD will give subscribers to the community solar project a fixed energy credit of $0.06/kWh for 20 years for the output from their share of the solar panels. That, combined with a $0.16/kWh Washington State energy credit, which lasts for eight years, yields an estimated eight-year payback for purchasers of solar energy units.

Sunshine varies widely through the year in the Pacific Northwest. In the summer, Snohomish PUD estimates the 500-kW solar farm could power about 100 homes. In the summer, that figure drops to about 20 homes.

The solar farm will be the main power source for Snohomish PUD’s planned microgrid at a site near the Arlington airport. The solar panels are all in place and wired up and are expected to begin generating power in May, Swaney said.

The microgrid, which will also include an energy storage battery and charging stations for vehicle-to-grid electric vehicles, is not expected to be in service until 2020.

The charging stations are part of a pilot program Snohomish PUD is conducting to determine the viability of using electric vehicles to inject power into the grid. The pilot program will only be available to two electric vehicles Snohomish PUD is buying for the project.

The total price tag for the microgrid project is $12 million, of which $3.5 million came from the Washington Clean Energy Fund, which is managed by the Department of Commerce. The cost of the solar array - about $900,000 - is being covered by customers’ subscription fees.