Former New York City Mayor Michael Bloomberg is giving the Sierra Club another $30 million to attack the coal industry as part of the environmental group’s campaign to shut down coal plants and mines across the country.

Bloomberg’s $30 million boost to the Sierra Club follows a $50 million commitment the former mayor gave the group in 2011 which was used to lobby for stricter federal environmental regulations and engage in litigation against coal plant operators.

“It will help us continue to run the largest campaign in the Sierra Club’s history and we think one of the most important in our history,” Sierra Club Executive Director Michael Brune told the National Journal.

According the Sierra Club’s “Beyond Coal Campaign,” they have contributed to the closing of  187 coal-fired power plants. But even this number is still less than half their goal of retiring 265 gigawatts of coal power.

“Every time we retire a coal plant and replace it with clean energy, that means we are cutting carbon, cutting air and water pollution, increasing the amount of clean energy on the grid and increasing the amount of jobs at the same time,” Brune said.

Bloomberg’s Sierra Club spending comes before the EPA is set to finalize regulations that the coal industry says will force hundreds of more coal-fired generators to prematurely retire. EPA rules have been subject to legal challenges by at least a dozen states and the coal company Murray Energy.

Bloomberg himself has used funding of eco-groups to boost his credentials as a billionaire who cares about the environment — last year, the former mayor even joined fellow billionaires Tom Steyer and Hank Paulson in putting out a report on the risks of global warming.

Bloomberg’s funding also comes as the White House once again ties global warming to public health issues. At the announcement of the funds, a high schooler from Alexandria, Virginia was brought on stage to thank the Sierra Club and Bloomberg for closing coal plants because they used to give her asthma.

Mayor Bloomberg himself claimed that closing coal plants saved 22,000 lives since 2011 — since he says that 7,500 people die a year from burning coal.

Since 2011, the #BeyondCoal campaign has saved more than 22,000 lives by replacing coal plants with clean energy http://t.co/SRicvebBDz

— Mike Bloomberg (@MikeBloomberg) April 8, 2015

Bloomberg and the Sierra Club were also quick to tout the link between coal, global warming and asthma. Bloomberg wrote on CNN Money that for “closing just a single [coal] plant can prevent 146 asthma attacks, 47 heart attacks, and 29 premature deaths a year.”

But claims by Bloomberg, and the Obama administration, that global warming is making asthma worse have not been supported by much evidence. In 2010, the National Institutes of Health reported that the “direct impacts of climate change on asthma, respiratory allergies, and airway diseases need further study to evaluate the fraction of respiratory disease risk that can be attributed to climate change and potentially mitigated or avoided.”

Bloomberg’s initial $50 million gift to the Sierra Club in 2011 came after the group admitted to taking money from a natural gas company for years to attack the coal industry. From 2007 to 2010, the Club took $26 million from natural gas giant Chesapeake Energy to push for stricter regulations on burning coal for electricity — a competitor to natural gas-fired electricity.

After admitting to taking Chesapeake funds in early 2012, the group quickly turned around and started a “Beyond Natural Gas” campaign to rebuild their image.

“Exempting the natural gas industry from environmental protections was a terrible idea,” Brune wrote in an open apology letter in 2012. “It looks even dumber today, when the real risks that natural gas drilling poses to water supplies and critical watersheds are that much more apparent.”

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