Finding parking in a big city usually involves lots of circling, wasted time and a whole lot of luck.

With that in mind, officials in San Francisco are launching an ambitious, $23 million project to install sensors on 6,000 of the city’s 24,000 parking spots that will alert drivers to open spaces.

The sensors, which were developed by researchers at the University of California–Berkeley and adapted by the company Streetline, will use a city-wide wi-fi network to keep track of how many spaces are open by displaying them on street signs or on smart phones.

And if you’re too lazy to even cruise for the new signs in San Francisco, a separate Web site, www.gottapark.com, will let you reserve a parking spot in advance. The spots come from a database of private spaces put up for rent by their owners. People looking for extra gas money can rent out their driveways and businesses can rent out their spots by registering on the site. Users can search for a specific date, time and area and the availability is displayed. The rental fee is set by the spot’s owner.

The sensors and spot reservations could help curtail traffic woes and environmental concerns across the country. A recent study by a University of California urban planner found that nearly 30 percent of traffic congestion in major business cities was a result of hunting for parking. The study also found the time spent searching for spots would be equal to 38 trips around the world, burning 47,000 gallons of gasoline and producing 730 tons of carbon dioxide.

Mallory Simon, CNN.com Writer