Changes

|caption = 08635 at Kidderminster Apr April 2017

|power = Diesel Electrical, to be Hydrogen Electrical|status = Evaluation for repairUnder conversion

|othernos = D3802, H3802

|events3 = Re-powering with hydrogen-hybrid power pack

D3802 arrived on the SVR in April 2007 as a source of spares.<ref>[http://www.uklocos.com/final-results.asp?action=display&Id=5567 UKLocos.com]</ref> It The engine has crankshaft damage and was unfit for futher use. The locomotive was placed in store, latterly in [[Kidderminster Carriage Shed]] with sister [[BR Class 08 08896| 08896]].<ref>[http://www.svr.co.uk/MeetTheLoco.aspx?id=90 SVR "Meet The Loco" web page]</ref> In February 2017 it was moved to the [[Diesel Depot]] for evaluation for repair, possibly using the engine from [[BR Class 08 08896| 08896]].<ref>Unofficial SVR Facebook page, 12 February 2017</ref> The photograph shows the locomotive on display next to the Diesel Depot at the April 2017 [[Open House Weekend]]. In June 2017 it was confirmed the assessment was unsuccessful and [[BR Class 09 09107]] purchased as more cost effective than restoring D3802.

In 2021 the SVR teamed up with the University of Birmingham's Vanguard Sustainable Transport Solutions to work on the ''Harrier hydro shunter project'' in [[Diesel Depot| Kidderminster TMD]].<ref>[https://news.railbusinessdaily.com/heritage-railway-joins-forces-to-build-a-locomotive-for-the-future/ Longhorn, D., 'Heritage railway joins forces to build a locomotive for the future', Rail Business Daily, 23 April 2021] (Retrieved 23 April 2021)</ref> This will see the UK’s first-ever conversion of a diesel locomotive to run with a replacement hydrogen-hybrid power pack. Completion is expected in the summer of 2023.<ref>[https://www.youtube.com/watch?v=Qo1zp4knSs0 'Evolution of the Harrier Hydro Shunter - a project update'] on SVR YouTube (16 December 2022) (Retrieved 17 December 2022)</ref>

The SVR team consists of young volunteers who {{As of|2023|06|lc=y}} had largely completed a bodywork and mechanical overhaul, removing redundant parts as spares for the SVR's shunter fleet, and a repaint was underway. Little of the previous contents of the engine compartment have been retained.<ref>2023 Spring Diesel Gala depot tour</ref> Development of the prime mover is with Vanguard and the new power pack is awaited. It will use electrolysis to react hydrogen with oxygen, which generates an electric current, producing H2O as the exhaust. Hydrogen has zero emissions at rail level, though there will be carbon emissions from its transport and, possibly, manufacture.  Updates can be found on the [https://www.facebook.com/groups/443297120418002 H3802 Harrier Hydro Shunter Project] Facebook page.  The locomotive carries the number H3802 and carries a modified green livery, with full length white, red and beige stripes on the lower body.