Testing of the first 250 km/h Alstom SJ250 inter-city electric multiple-unit for Swedish operator SJ has begun at the VUZ Velim test centre in the Czech Republic, according to railwaygazette.com. The programme aims to obtain certification for operation in Sweden, Denmark and Norway.

In April 2022, SJ awarded Alstom its Project Delta contract to supply 25 Zefiro Express EMUs, with an option for 15 more. The €650m order is backed with €312m of financing from the European Investment Bank.

The trains are designated Class X250 and marketed by Alstom as the Avelia Stream Nordic. They will be the fastest trains used in commercial service in Sweden, with a maximum operating speed of 250 km/h compared to 200 km/h for older stock.

Each six-car train will have 363 seats, with fold-out tables, footrests, cup holders, power outlets and USB ports. There will be a bistro area and dedicated bicycle spaces.

The fleet is designed to operate reliably in temperatures ranging from -40°C to +40°C, reflecting the demanding Nordic climate. The trainsets will be equipped with batteries to enable movement if the power supply fails.

Deliveries were originally scheduled to begin in 2026, but entry into passenger service has slipped to December 2027. SJ has attributed the delay to supply chain disruptions.

The trainsets will initially be deployed on the Stockholm – Göteborg, Stockholm – Malmö and Stockholm – Sundsvall – Umeå routes, supplementing and eventually replacing the oldest X2000 trainsets.

While infrastructure constraints will initially limit operating speeds on some sections, the ongoing rollout of ERTMS and targeted infrastructure upgrades will allow increasing use of the 250 km/h capability.

The Stockholm – Malmö route includes sections already designed or being upgraded for 250 km/h operation, while the Stockholm – Sundsvall – Umeå corridor is particularly well suited to the new fleet because the Botniabanan was built for 250 km/h running.

SJ expects the introduction of the X250 fleet to significantly increase capacity, with the number of seats increasing by 63% between Stockholm and Gävle, 63% between Stockholm and Sundsvall and 88% between Stockholm and Umeå; the operator also plans to increase the number of daily Stockholm – Umeå services from four to five.

In the longer term, certification for Sweden, Denmark and Norway will support plans to expand international services, particularly to København and Oslo.