(August 14, 2019) — New analysis by Wood Mackenzie finds that the transition to a 100% renewable U.S. power grid will need an investment of up to $4.5 trillion over the next 10 to 20 years. The Edinburgh, Scotland-based global consultancy estimates that about 1600 gigawatts (GW) of new wind and solar capacity would be needed to produce enough energy to replace all fossil fuel generation in the U.S.

“The mass deployment of wind and solar generation will require substantial investments in utility-scale storage to ensure grid resilience is maintained,” says Dan Shreve, head of global wind energy research at Wood Mackenzie. About 900 GW of new storage will be needed to ensure wind- and solar-generated power is available exactly when consumers need it. The scale of the challenge is unprecedented, requiring a complete redesign of the power sector.

“The challenges of achieving 100% renewable energy go far beyond the capital costs of new generating assets,” Shreve observes. “Most notably, it will need a substantial redesign of electricity markets, migrating away from traditional energy-only constructs and more toward a capacity market.”

Wood Mackenzie reports the existing U.S. power grid has about 1060 GW of nameplate capacity, including roughly about 130 GW of wind and solar capacity. Aggressive climate targets for the year 2030 would require more capacity to be installed every year for the next 11 years than the total capacity that was placed into service over the previous 20-year period.

However, extending the time horizon to a 2040- to-2050 timeframe would allow new technologies to develop and reach commercial scale. Further, allowing 20% of the power mix to come from the natural gas-fired generation now in place would also reduce renewable costs by about 20%, and energy storage costs by at least 60%, Wood Mackenzie finds.

“Over the past six months, Wood Mackenzie analyzed the actual hourly wind and solar generation patterns from all major U.S. power markets,” comments Wade Schauer, director of Americas Power Research. “The data suggests that reaching 50% of supply from intermit- tent renewables system-wide is relatively straightforward in most of the U.S. Above 50%, integration challenges accelerate rapidly. Achieving full decarbonization will require long-duration energy storage, and the electric grid will need to roughly double its capacity.”

(SOURCE: The Weekly Propane Newsletter)