The beverage company will start selling four varieties of its energy drink — Coca-Cola Energy, Coca-Cola Energy Zero Sugar, Coca-Cola Energy Cherry and Coca-Cola Energy Cherry Zero Sugar — in the United States in mid-January. Coke Energy and Coke Energy Zero Sugar are already available internationally, but the cherry flavor is new.

The new product is designed to help Coke to introducedrinkers, who may not consume energy drinks, to a growing category. It's also a way for the company to make sure that its core Coca-Cola brand remains fresh.

But first, Coca-Cola has to make sure drinkers understand just what Coke Energy is.

Four varieites of Coca-Cola Energy are coming to the United States in January.

A boost of energy

Coca-Cola Energy has 114 mg of caffeine in each 12-ounce serving.That's nearly four times the caffeine in a can of regular Coca-Cola (34 mg), and three times the caffeine in a can of Diet Coke (46 mg).

It will be more expensive, too: Coca-Cola Energy will have a recommended price of $2.49 per 12-ounce container. Similarly-sized regular Cokes are generally sold in packs of 12, and cost about $4 per package (about 33 cents each).

In the United States, total energy drink and energy shot sales reached about $13.5 billion in 2018, up 30% from 2013, according to a report from research group Mintel. The sector could have sales of about $17 billion in 2023, Mintel projects.

Coke drinkers aren't really in on the trend, according to Coca-Cola Brand Director Janki Gambhir.

"Many consumers that drink Coke don't engage in the energy category today," she told CNN Business, noting that they still may be interested. "A lot of the work that we will do will be focused around educating consumers," she said.

To figure out how to make Coke Energy work in the United States, the company spoke with more than 1,100 people — including energy drink consumers and those that don't regularly drink the beverage — to make sure that it delivers what people want. The company plans to introduce the product by advertising it through television commercials and billboards, as well as handing out samples.

With Coca-Cola Energy, the company hopes to boost sales within the Coke brand rather than steal share from other energy drinks or Coke flavors. Coca-Cola owns about 18% of Monster Energy, and has a strategic partnership with the company.

In addition to giving Coca-Cola another way into the energy sector, Coke Energy can help make sure people don't stop drinking Coke.

Keeping Coke current

Coca-Cola has ambitions of being a "global beverage company." It sells iced tea, juice, water, coffee and smoothies. But Coke is its core business, and only a few years ago the Coke brand was stagnating

So far, Coca-Cola's efforts to revitalize its core brand seem to be working. Second quarter sales were driven in part by 4% global growth in trademark Coca-Cola, the company said. And international sales of Coke Energy are "encouraging," said CEO James Quincey in a July call discussing the quarter's financial results .

Coca-Cola hopes that Coke Energy will be a continued source of long term growth, said Gambhir, adding that there is a "pipeline full of new flavors" and other innovations for the platform.