You've heard of hybrid cars, but now, the city of Annapolis has a hybrid boat patrolling its harbor.

In a press conference Thursday afternoon, Annapolis Mayor Josh Cohen and Harbormaster Flip Walters unveiled the first of two hybrid diesel-electric-solar propulsion systems mounted on Harbormaster boats.

The first boat, on display Thursday afternoon, will be used to collect mooring fees and as a water rescue boat as needed, city officials said. The second boat is the city's pumpout boat, which is currently being converted to an identical system. That boat is scheduled to be ready in January, officials said.

The boats are not new, but were repurposed with the hybrid systems, city officials said. The entire process took about four years.

According to a city spokeswoman, there are only 12--including the two in Annapolis---such systems worldwide.

The price tag for such a project was $400,000, and it was all funded by grants, city officials say. Of that total, roughly $300,000 was funded by the Environmental Protection Agency, through a grant secured by the Mid-Atlantic Regional Air Management Association (MARAMA) under the Recovery Act. The additional $100,000 was funded by the Canadian government, city officials said.

"As part of the City’s Clean & Green initiative, this project addressed the need for resources on the water directly affecting the health of the Bay,” Cohen said in a statement.

Cohen also said the city hopes to see significant cost savings—roughly 50 percent over the life of the boat saved in fuel costs.

Several attending Thursday's event got the chance to take a ride on the boat.

Read more about the boat by visiting the city's website.