A pneumatic regenerative system for a railway vehicle equipped with a plurality of axles includes a plurality of pneumatic drive mechanisms coupled to each of the plurality of axles. Each pneumatic drive mechanism includes an accumulator and a pneumatic device. The pneumatic device may in some examples be a reversible air motor device. The accumulator is operable to receive and store pressurized air. The reversible air motor device is coupled to the accumulator and one of the plurality of axles of the vehicle. The reversible air motor device is operable in a first configuration and a second configuration. During a braking operation of the railway vehicle, the reversible air motor device in the first configuration is driven by rotation of the one of the plurality of axles to generate and store pressurized air in the accumulator. During an acceleration operation, of the railway vehicle the reversible air motor device receives pressurized air from the accumulator to drive rotation of the one of the plurality of axles.

A pneumatic regenerative system for a railway vehicle equipped with a plurality of axles includes a plurality of pneumatic drive mechanisms coupled to each of the plurality of axles. Each pneumatic drive mechanism includes an accumulator and a pneumatic device. The pneumatic device may in some examples be a reversible air motor device. The accumulator is operable to receive and store pressurized air. The reversible air motor device is coupled to the accumulator and one of the plurality of axles of the vehicle. The reversible air motor device is operable in a first configuration and a second configuration. During a braking operation of the railway vehicle, the reversible air motor device in the first configuration is driven by rotation of the one of the plurality of axles to generate and store pressurized air in the accumulator. During an acceleration operation, of the railway vehicle the reversible air motor device receives pressurized air from the accumulator to drive rotation of the one of the plurality of axles.

A pneumatic regenerative system for a railway vehicle equipped with a plurality of axles includes a plurality of pneumatic drive mechanisms coupled to each of the plurality of axles. Each pneumatic drive mechanism includes an accumulator and a pneumatic device. The pneumatic device may in some examples be a reversible air motor device. The accumulator is operable to receive and store pressurized air. The reversible air motor device is coupled to the accumulator and one of the plurality of axles of the vehicle. The reversible air motor device is operable in a first configuration and a second configuration. During a braking operation of the railway vehicle, the reversible air motor device in the first configuration is driven by rotation of the one of the plurality of axles to generate and store pressurized air in the accumulator. During an acceleration operation, of the railway vehicle the reversible air motor device receives pressurized air from the accumulator to drive rotation of the one of the plurality of axles.

A pneumatic regenerative system for a railway vehicle equipped with a plurality of axles includes a plurality of pneumatic drive mechanisms coupled to each of the plurality of axles. Each pneumatic drive mechanism includes an accumulator and a pneumatic device. The pneumatic device may in some examples be a reversible air motor device. The accumulator is operable to receive and store pressurized air. The reversible air motor device is coupled to the accumulator and one of the plurality of axles of the vehicle. The reversible air motor device is operable in a first configuration and a second configuration. During a braking operation of the railway vehicle, the reversible air motor device in the first configuration is driven by rotation of the one of the plurality of axles to generate and store pressurized air in the accumulator. During an acceleration operation, of the railway vehicle the reversible air motor device receives pressurized air from the accumulator to drive rotation of the one of the plurality of axles.

An apparatus for generating electricity from water flow comprises a convergent section, a diffuser section and tube for locating within a body of water. The convergent section is connected to a first end of a mixing chamber such that a venturi is defined between the end of the convergent section and the mixing chamber. The diffuser section is connected to a second end of the mixing chamber, the diffuser section configured such that in use the pressure at the exit of the diffuser section is greater than the pressure at the venturi. At least part of the tube is located in the convergent section, such that an annulus is defined between the tube and the convergent section, to form a first flow passage. The tube defines a second flow passage within the tube; and a turbine connectable to a generator is located within the tube.