Mobile device charging service provider Energy Monster, which went public in the U.S. last month, turned a profit in the first quarter of 2021 as its revenue and number of power bank rental locations grew significantly.

Shanghai-based Energy Monster logged a net profit of 15.1 million yuan ($2.3 million) in the first quarter, in sharp contrast to a 137.5 million yuan loss in the same period last year, according to its latest earnings report released on Wednesday. However, it is important to note that last spring was a period in which Covid-19 swept through China, forcing people to stay indoors (and close to their own charging devices) to avoid infection.

The change in fortunes came as the company’s revenue more than doubled to 846.9 million yuan, about 96% of which came from its mobile device charging business, which generated 816.8 million yuan in revenue, representing a year-on-year increase of 164.5%.

Energy Monster attributed the healthy growth in its core business to a robust increase in its number of power bank rental locations, which rose to 716,000 at the end of March from 664,000 a year ago. As of the end of March, the company had 235.8 million registered users, 16.4 million more than it had at the end of the same month in 2020.

Four-year-old Energy Monster provides table-mounted and portable chargers at public places including bars, hotels, restaurants, convenience stores, entertainment venues and transportation hubs. It also makes money through sales of power banks and advertising services.

Energy Monster CEO Cai Guangyuan said the company will continue to adopt a dual-track strategy of stepping up its presence in both low-tier and high-tier cities across China, where the value of the mobile device charging service market is forecast by iResearch to reach 106.3 billion yuan in 2028.

In the second quarter, Energy Monster said that its revenue may reach between 940 million yuan and 970 million yuan.

Contact reporter Ding Yi (yiding@caixin.com)

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