Acumulador de Carga Rápida

Trams equipped with ACR are fast-charged while at stops; elsewhere they require no overhead line, which is desirable for reasons of safety, reliability, cost, and aesthetics.

[1][2] It also allows regenerative braking where direct current electrification systems cannot return (much) energy to the grid.

[citation needed] ACR-equipped trams are powered between stops by discharging a rooftop supercapacitor battery, weighing around 1 tonne (2,200 lb), which gives a range of around 2 miles (3.2 km).

ACR's first commercial installation was aboard Urbos trams supplied to MetroCentro in 2011, allowing the permanent removal of overhead lines around the cathedral.

[3] Line 1 of the Tranvía de Zaragoza has also used ACR since its second construction phase was completed in 2013.

An ACR-equipped Urbos 3 tram running through central Seville without overhead line , 2015. The supercapacitor batteries are visible on the roof of each end car.