The battery boom is coming to China, California and basically everywhere else – and it will be even bigger than previously thought.

The global energy-storage market will surge to a cumulative 942 GW by 2040, according to a new forecast from Bloomberg NEF published on November 13, and that growth will necessitate $620-billion in investment.

Sharply falling battery costs is a key driver of the boom. BNEF sees the capital cost of a utility-scale lithium-ion storage system falling another 52% by 2030.

But cost isn’t the only factor. Governments from China to California are spurring demand, as is the rise of electric vehicles and solar power. There’s also been a greater focus on storage for electric-vehicle charging as well as energy access in remote areas.

“Costs have come down faster than we expected,” Yayoi Sekine, a New York-based analyst at BNEF, said in an interview. “Batteries are going to permeate our lives.”

The implications of cheaper batteries are far-reaching, upending multiple industries and helping spur technologies necessary to help fight climate change. Batteries power the electric vehicles that are popping up on our freeways. They also unlock solar power from the exclusive confines of the sun.

Two important markets come into particular focus. China, which is building up its battery-manufacturing capacity, will be a central player in the boom.

California, meanwhile, has pushed through a series of measures in recent years that will directly or indirectly spur more batteries, including legislation that would require all of the state’s electricity to come from carbon-free sources by 2045.

“Storage is just so sensibly the next step in the evolution of renewable energy,” Edward Fenster, the executive chairperson of San Francisco-based rooftop-solar company Sunrun, said in an interview. “If we’re going to get to 100% renewable energy, we’ll need storage.”

Six key takeaways from the latest BNEF battery forecast:

• Annual energy-storage deployments are now forecast to exceed 50 GWh by 2020. That’s three years earlier than BNEF’s outlook from just last year.
• Energy storage may be equivalent to 7% of the world’s total installed power capacity by 2040.
• The Asia-Pacific region will be home to 45% of total installations on a megawatt basis by 2040. Another 29% will be spread across Europe, Middle East and Africa. The remainder will be in the Americas.
• The majority of storage capacity will be utility-scale until the mid-2030s. But then so-called behind-the-meter projects— installations at businesses, industrial sites and residential properties—will overtake utility-scale.
• A list of the leading battery countries is topped by: China, the US, India, Japan, Germany, France, Australia, South Korea and the UK. South Korea today dominates the market but will be overtaken by the US early in the 2020s—and both will later be eclipsed by China.
• Storage is coming to developing countries in Africa, too. BNEF explains it thusly: utilities will likely recognize that the combination of solar, diesel and batteries in “far-flung sites” is cheaper than extending the power grid or building a fossil-only generator.