From solar panel installers to electric vehicle factory workers, the clean energy sector lost more than 100,000 U.S. jobs in March as stringent measures to control the new coronavirus shut down manufacturing and halted plans for home and business upgrades.

The job loss estimates are based on an analysis of Department of Labor unemployment claims published on Wednesday by BW Research for clean energy business groups E2, the American Council on Renewable Energy and E4TheFuture.

They are a devastating blow to an industry that has logged more than 10% job growth in the last five years -- a faster pace than the broader U.S. workforce. Yet they represent a small fraction of the jobs lost in the U.S. economy overall as 16.8 million people filed for unemployment benefits in the last three weeks.

The clean energy sector, as defined in the report, includes solar and wind company workers, electricians, roofers and plumbers who install energy-efficient products, and factory employees who make everything from hybrid cars to LED lighting to efficient appliances.

There were 3.36 million workers in the sector at the end of 2019, an increase of more than 70,000 from a year earlier, according to E2.

The March job losses, therefore, erased all the industry's gains from 2019, and then some. The analysis projects that more than 500,000 jobs, or 15% of the clean energy workforce, could be lost in the next few months.

"What these numbers tell us is that clean energy workers are a huge and important part of America's workforce -- and they are hurting badly," Bob Keefe, executive director of E2, said in a statement.

Energy efficiency jobs accounted for 70% of the losses, the analysis found, because construction workers and energy auditors were unable to enter homes and businesses due to stay-at-home orders.

Renewable energy lost 16,000 jobs and the clean vehicle industry shed 12,000 workers, the analysis found.

Wind and solar companies have been pleading with Congress to extend deadlines for projects to qualify for sunsetting federal tax credits. Those requests were not included in the $2 trillion coronavirus aid package passed last month, but the sector is hopeful that they will be included in subsequent legislation.

California, North Carolina, Pennsylvania, Massachusetts and Michigan were the states hit hardest by the sector's losses.