Former New York City Mayor Michael Bloomberg announced on Wednesday he will pump $500 million into the next phase of his energy transition campaign, aiming to shut down “every last” coal plant in the United States and slash gas-fired capacity in half by 2030.

The $500 million infusion into his decade-long Beyond Carbon initiative aims to “finish the job on coal” by working with state and local organizations to force the closure of the roughly 150 coal plants that have not yet retired, slash current gas generation in half and block the construction of new gas-fired plants.

Bloomberg already has spent over $500 million to support the Sierra Club’s Beyond Coal campaign, which originally aimed to retire 30% of the U.S. coal fleet by 2020. The campaign ended up accelerating the retirement of over 60% of coal plants by that year and putting $85 million toward a similar mission to fight the expansion of petrochemical plants in the U.S.

“By working with our partners across the country, we hope to transform the way we power America by moving beyond fossil fuels and replacing them with renewable energy,” said Bloomberg, who is the U.N. Special Envoy on Climate Ambition and Solutions.

The money would support litigation brought against utilities and power companies by grassroots groups, state and local policy advocacy and financing to assist local communities with coal plant closures, Bloomberg Philanthropies said.

U.N. Secretary-General Antonio Guterres told a climate summit at the annual high-level U.N. General Assembly that time was running out to tackle climate change, thanks in part to the “naked greed” of fossil fuel interests.