Citi Bike, New York City’s bike share program, celebrated its first birthday earlier this week by offering riders one dollar day passes, along with free cupcakes at select stations. The program has evolved significantly in the past year, and despite some initial resistance and technical glitches Citi Bike now boasts more than 104,000 annual members.

Bike share programs are booming across the US and around the world, with cities implementing various strategies to garner public support, receive sufficient funding, and maintain successful programs overall. No matter what the final product looks like, bike shares are a great way to encourage citizens to make their commute, or even their leisurely weekend travel, more energy efficient.

The first large-scale, urban bike sharing program utilizing specially designed bicycles was launched in Copenhagen in 1995. Bycyklen encountered financial difficulties, mainly due to vandalism and theft, and most locals considered the bikes to be tourist traps and resisted using them. As with any new technology or transport systems, cities have since learned from one another and are launching successful programs more smoothly.

In recent years, cities have become even more innovative with their bike shares. Madrid recently launched a program utilizing electric bikes, supported by 37 miles of additional bike lanes throughout the city. Since riders no longer have to worry about distance or hills, electric bike shares make energy efficient commutes from one part of the city to another possible.

Seattle is the most recent U.S. city to announce a program – the Pronto Emerald City Cycle Share will kick off in September 2014 with 50 docking stages and 500 bikes. Portland, Oregon, Tampa, San Diego, and Vancouver, B.C. are also planning to launch programs in the near future, adding to the 30 plus American cities that already have programs. Bike shares are quickly becoming the norm around the world, and will only continue to increase the possibilities for energy efficient commutes in the future.