| British Rail Class 799 HydroFLEX | |
|---|---|
 The prototype unit, number 799001 | |
| Manufacturer |
|
| Family name | BR Second Generation(Mark 3) |
| Constructed | 2019, 2021 |
| Number built | 2 |
| Number scrapped | 1 |
| Formation | 4 cars per unit |
| Fleet numbers | 799001, 799201[1] |
| Specifications | |
| Car body construction | Steel |
| Car length |
|
| Width | 2.816 m (9 ft 2.9 in) |
| Height | 3.774 m (12 ft 4.6 in) |
| Wheelbase | Over bogie centres:14.17 m (46 ft 6 in) |
| Prime mover(s) | Ballard FCveloCity |
| Engine type | Hydrogenfuel cell |
| HVAC | Electric heating |
| Electric system(s) | |
| Current collection |
|
| Braking system(s) | Electro-pneumatic (disc) |
| Safety system(s) | |
| Coupling system | Tightlock |
| Track gauge | 1,435 mm (4 ft 8+1⁄2 in)standard gauge |
TheBritish Rail Class 799HydroFLEX is a prototype class of bi-mode[3] multiple unit adapted fromClass 319 electric multiple units (319001/382). The existing25 kVAC and 750VDC equipment has been retained with ahydrogen fuel cell added, currently taking up one of the carriages.
The Class 319 units were built byBREL between 1987 and 1990 forNetwork SouthEast, as dual-voltage units to run onThameslink services. In late 2014,Govia Thameslink Railway began returning its allocation ofClass 319 units toPorterbrook (the owner of the units) as they were gradually replaced byClass 387 units and then ultimatelyClass 700 units onThameslink services.
In September 2018,Porterbrook announced it would develop ahydrogen fuel cell demonstrator in partnership with theUniversity of Birmingham's Centre for Railway Research and Education. In December 2018, Porterbrook procured an FCveloCity fuel cell unit fromBallard Power Systems.[4]
The first unit was converted from aClass 319 unit that had last been used byGovia Thameslink Railway.[5][3][6] It was unveiled on 20 June 2019.[7][8][9] In June 2019, it was announced that approval for mainline testing of the unit (branded asHydroFLEX) had been granted after a period of demonstration at Rail Live 2019.[10]
The first mainline testing occurred in September 2020, reaching 50 mph (80 km/h) through Warwickshire. The next phase of the development of this prototype is move the hydrogen tanks and fuel cell from one of the carriages and suspend them beneath the train.[11]
A second unit was presented at theCOP26 Summit at Glasgow with one of the DT car's passenger doors removed and permanently sealed. The TSOL has also been reconfigured with a boardroom-styled interior specially for the summit.[12]
| Subclass | Quantity converted | Year converted | Cars per unit | Unit numbers | Converted from[13] | Notes |
|---|---|---|---|---|---|---|
| 799/0 | 1 | 2019 | 4 | 799001 | 319001 | Scrapped.[14] |
| 799/2 | 1 | 2021 | 799201 | 319382 | Unveiled at COP26 in Glasgow. |
... BCRRE said that the demonstrator version focuses on delivering an electric/hydrogen bi-mode to UK gauge ...