Adelaide's Solar Buses Could Be the World's Greenest Public Transports

Australia has wholeheartedly embraced solar power over the last few years, with usage exploding 10-fold between 2009 and 2011 and the price per watt falling to less than half that of grid power. Now, the southern Australian city of Adelaide is taking the unprecedented step of powering its public transit system solely through solar as well.

As of 2010, some 36 percent of the city's carbon emissions were generated by transportation—both public and private. In response, the Adelaide city council has implemented a sustainability plan including extensive pedestrian walkways and bike paths as well as the new fleet of Tindo (Aboriginal for "sun") buses.

But these are very unique buses. Unlike the gas-powered or hybrid fleets found around the world, the Tindo is completely electric so it's zero emission, and unlike San Francisco's MUNI, it doesn't draw power from overhead lines. In fact, the bus doesn't power itself at all. That is, there aren't any solar panels actually on the vehicle itself. Instead each bus charges like an overgrown Roomba at the Adelaide Central Bus Station before setting out on its routes around town. In average traffic conditions, the Tindo can cover 200 km (about 125 miles) before needing to recharge, thanks in part to a regenerative braking system that increases the vehicle's energy efficiency by some 30 percent.

Manufactured by New Zealand company Designline International, each carbon neutral vehicle can accommodate up to 40 riders at a time and offers both A/C and free Wi-Fi for riders. What's more, the entire bus service itself is available to the public at no charge.

The first of these buses rolled out this past February and in the 15,000 km they've traveled since then, they've saved an estimated 70,000 kg (154,000 pounds) of carbon emissions and 14,000 liters (nearly 3,700 gallons) of diesel fuel. That's just seven months. Fossil fuel's days are numbered. [Adelaide City Council via Clean Technica]