[1][2] After the failure of the Seattle Commons plan in the 1990s, which proposed a large city park over the neighborhood, the land was opened for development by Paul Allen's Vulcan Real Estate, which envisioned it as a hub for biotech and high tech firms.

[25] The 110,000 sq ft (10,000 m2) substation, designed by architectural firm NBBJ, is shaped in the form of an acute trapezoid, with its longest side facing Denny Way.

[27] The outer walls use 35-foot-high (11 m) stainless steel panels (16 feet (4.9 m) above street level)[26] with a 1⁄4-mile (0.40 km) elevated pedestrian ramp to provide views of the cityscape and the substation's interior.

On the exterior walls of the substation house Ned Khan's Switchwall, consisting of a strip of colored lights that change based on wind flows.

[36][37] Lead designer John Savo of NBBJ stated that they "[didn't] want it to be your grandfather's substation", desiring a facility that would "engage [with] the community, to make it an amenity and not a distraction".

[39][40] After the completion of design work and environmental cleanup in 2015, the substation's cost was revised to $210 million because of unexpected soil contamination and the need for newer electrical equipment.

[41][42] The substation's construction costs are funded by Seattle City Light through regular rate increases for customers as part of their six-year Strategic Plan.

[45][46] The use of a gas-insulated switchgear in the Denny Substation allowed for a smaller footprint;[23] the facility also uses solar cells to produce its electricity and a heat recovery system.

[28][47][48] Outside consultants hired by the city government in 2018 later concluded that the overall demand in the Denny Triangle and South Lake Union area would rise to 60 megawatts by 2027, far below the 180-megawatt capacity that the substation was designed for.