VDL Citea: the low-floor city bus that went electric

The VDL Citea is a family of low-floor city and regional buses built by VDL Bus & Coach. The first version, the Citea CLF, was shown at the UITP Mobility and City Transport Exhibition in Helsinki in 2007, and the series was facelifted in 2010 and thoroughly reworked in 2020. Its electric versions made VDL one of the larger suppliers of battery buses in Europe.

VDL Citea at a glance

Based on the English and Dutch Wikipedia articles; the technical description of how the buses are assembled comes from the Dutch page.

History of the VDL Citea

The Citea was presented in 2007 at the UITP Mobility and City Transport Exhibition in Helsinki. The first model, the Citea CLF, had a completely flat floor and opened a range of buses for public transport. Its arrival ended production of the Jonckheere SB 250 city bus in its 12-metre form and of the Berkhof Diplomat. The construction was based on the lightweight systems that VDL Berkhof in Heerenveen had used for years on the Berkhof Ambassador, such as the bolted joints between roof, side frames and side panels, which allowed quick repairs after a collision without major dismantling.

Orders and revisions

The first ten Citeas were ordered in 2008 by the Dutch operator Connexxion. In November 2008 the Roads and Transport Authority of Dubai ordered 518 buses, the first of which were delivered on 29 June 2009; those buses had a partition between the men’s and women’s sections, with the first three rows reserved for women, children and families. In April 2011 GVB of Amsterdam ordered 70 Citeas. In January 2013 Rheinbahn ordered 60 Citea LLEs, after two test vehicles of the lightweight model had saved more fuel in a two-year trial than a hybrid bus tested by the same operator. In 2014 Berliner Verkehrsbetriebe signed a contract for up to 236 Citeas; 40 were delivered in 2015 and another 70 by 2016, and in October 2016 BVG said it would keep the 110 vehicles already delivered. On 23 September 2010, at the IAA in Hanover, the Citea was named Bus of the Year 2011. A new design by Van der Veer Designers of Geldermalsen followed in 2010, recognisable by a large VDL logo on the front, and the range was overhauled again in 2020.

Hybrid and electric

On 1 December 2010 two CLF120 Hybrid Citeas of Connexxion were presented in Enschede, using hybrid technology from Vossloh Kiepe and developed with TU Darmstadt; in March 2011 three SLF120 Hybrids went to HEAG mobiBus. The electric range began with the Citea SLF Electric, a twelve-metre all-electric low-floor bus whose drives and battery packs the buyer can choose. The Citea SLFA 181 Electric, an 18.1-metre articulated bus, was shown in May 2015 at the UITP World Congress in Milan. Its 1,380 kg lithium-ion battery holds 122.6 kWh and is fast-charged by a pantograph on the roof above the second axle, with up to 250 kW at the final stops; the bus seats 43 and carries 82 standing passengers. It has been used since 2016 on Cologne line 133 with eight vehicles and, from December 2016, by Hermes in Eindhoven, which runs 43 of them as the ‘Bravo’ fleet, one of the largest electric bus fleets in Europe. Schiphol Busnet and the R-Net lines between Schiphol, Amsterdam and Haarlem use the same buses. On 8 June 2020 an R-Net Citea SLF-120 on line 436 between Rotterdam and Goeree-Overflakkee was tested with a trailer carrying hydrogen tanks and fuel cells as a range extender, giving a range of up to 350 km.

How a Citea is built

A Citea body shell is assembled in about fifteen working days from parts made elsewhere. The steel chassis, of St37K steel galvanised after production, comes from VDL Bus Chassis in Eindhoven; the body parts come from VDL Postma in Heerenveen, made of 3CR12 stainless steel, a middle ground between ordinary and stainless steel. Plastic side panels are painted in the required colour in Irnsum, the roof is made of aluminium elements, doors come from Bolsward and the fronts largely from the Czech Republic. On the SLF the engine sits at the left rear, with radiator, oil cooler and intercooler moved into the body above it; on the SLE and LLE the engine is at the rear in the middle.

Design and features

• Flat floor and low entry: the CLF has a fully flat floor, while the CLE and the lightweight LLE are low-entry buses.
• Modular body: bolted joints and a modular system let the bus be adapted to the requirements of operators in different countries.
• Tower engine: on the SLF the engine is mounted at the left rear, with the cooling pack above it.
• Electric drive: the SLF Electric and the articulated SLFA 181 use pantograph fast charging at up to 250 kW.
• Accessibility: a manual or electric wheelchair ramp is fitted for wheelchair users.

VDL Citea versions

• Citea CLF: the original low-floor city bus with tower engine, launched in 2007.
• Citea CLE and LLE: low-entry and light low-entry versions; the LLE was ordered in large numbers by Rheinbahn.
• Citea MLE: midi low-entry bus presented at Busworld 2013, developed with Wrightbus and based on the Wright StreetLite for left-hand-drive markets, in lengths from 8.8 to 10.8 m.
• Citea DLF 114: double-deck low-floor prototype handed over on 11 August 2015 and tested in Berlin from October 2015.
• Citea SLF and SLFA Electric: twelve-metre and 18.1-metre articulated battery buses.
• Citea SLF120 Hybrid: hybrid version with Vossloh Kiepe technology, presented in 2010.

The Citea carried on the lightweight construction of the Berkhof Ambassador, and it replaced the Bova Lexio interurban bus; see also VDL Bova. More vehicles are in the VDL collection.

Video: VDL Citea Electric

Video on YouTube.

Sources

• VDL Citea, English Wikipedia: history, orders, hybrid and electric versions
• VDL Citea, Dutch Wikipedia: construction, design, MLE and DLF, interior