GTM Research Report: 42 US states expected to hit grid parity by 2020

GTM notes that California, Massachusetts and Hawaii stand as the most attractive US states for solar today. Image: Elliott Brown / Flickr

A new report from GTM Research — U.S. Residential Solar Economic Outlook: Grid Parity, Rate Design and Net Metering Risk — sheds light on the growing residential solar market in the US.

According to the report, 20 US states are currently at grid parity, while 42 states are expected to hit the same threshold by 2020 under normal conditions.

Residential PV hits grid parity when the established cost of solar energy dips below the gross electricity bill savings in the first year of a PV system’s operation.

When it came to weighing current net metering rules, rate design and incentives, California, Massachusetts and Hawaii led the way in the US in terms of residential solar attractiveness. In each of those three states, solar can cut an average customer’s electricity bill by 20% to 40% during the first year of a system’s life. GTM Research also noted that North Dakota, Oklahoma, and Washington are the least attractive states for PV today.

Cory Honeyman, senior GTM Research analyst and lead author of the report, said: “To date, the residential solar market’s growth has primarily come from a handful of states where favorable rate structures and net metering rules have set high, predictable ceilings on savings due to solar.

“But with more and more utilities reevaluating net metering rules and rate design, the residential solar economic outlook can no longer depend on a static policy landscape that fueled the nearly one million homeowners now with rooftop solar. Looking ahead, it is no longer a question of if, but rather, when and to what extent rate structures and net metering rules are revised.”

Tags: gtm research, united states, california, grid parity, massachusetts, hawaii