The Alexander Dennis Enviro400EV is a battery electric

double-decker bus A double-decker bus is a bus that has two storeys or decks. Double-deckers are used primarily for commuter transport, but open-top models are used as sightseeing buses for tourists, and there are coaches too for long-distance travel. They app ...

produced by the British bus manufacturer

Alexander Dennis Alexander Dennis is a British bus manufacturing company based in Larbert, Scotland. The largest bus and coach manufacturer in the United Kingdom, with a 50% market share in 2019, it has manufacturing plants and partnerships in Canada, China, ...

in partnership with Chinese electric vehicle manufacturer

BYD Auto BYD Auto Co., Ltd. ( zh, s=比亚迪汽车, p=Bǐyàdí Qìchē) is the Automotive industry, automotive subsidiary of BYD Company, a publicly listed Chinese multinational manufacturing company. It manufactures passenger battery electric vehicle ...

since 2018. Based on its

Alexander Dennis Enviro400 City The Alexander Dennis Enviro400 City is a low-floor bus, low-floor double-decker bus produced by the British bus manufacturer Alexander Dennis since 2015, as an alternative to the standard Alexander Dennis Enviro400 MMC bodywork. The Enviro400 C ...

body, which was launched in 2015 to compete with the

hybrid electric A hybrid electric vehicle (HEV) is a type of hybrid vehicle that couples a conventional internal combustion engine (ICE) with one or more electric engines into a combined propulsion system. The presence of the electric powertrain, which has i ...

New Routemaster The New Routemaster, originally referred to as the New Bus for London and colloquially as the Borismaster or Boris Bus, is a low-floor Hybrid electric bus, hybrid diesel–electric double-decker bus operated in London, England. Designed by Tho ...

, the Enviro400EV is produced at Alexander Dennis'

Falkirk Falkirk ( ; ; ) is a town in the Central Lowlands of Scotland, historically within the county of Stirlingshire. It lies in the Forth Valley, northwest of Edinburgh and northeast of Glasgow. Falkirk had a resident population of 32,422 at the ...

and

Scarborough Scarborough or Scarboro may refer to: People * Scarborough (surname) * Earl of Scarbrough Places Australia * Scarborough, Western Australia, suburb of Perth * Scarborough, New South Wales, suburb of Wollongong * Scarborough, Queensland, sub ...

factories in the United Kingdom, with production of the type at the company's

Larbert Larbert (, ) is a town in the Falkirk (council area), Falkirk council area of Scotland. The town lies in the Forth Valley above the River Carron (Forth), River Carron which flows from the west. Larbert is from the shoreline of the Firth of Fo ...

headquarters set to also commence in mid-2023. The Enviro400EV is available both as a complete integral battery electric bus and as a battery electric bus body on a

BYD K series The BYD K series bus (sometimes just referred to as the BYD ebus or BYD electric bus) are a line of battery electric buses manufactured by the China, Chinese automaker BYD Auto, BYD, powered with its self-developed lithium iron phosphate battery ...

chassis, as well the integral Enviro400FCEV

fuel cell bus A fuel cell bus is a bus that uses a hydrogen fuel cell as its power source for Electric motor, electrically driven wheels, sometimes augmented in a Hybrid power, hybrid fashion with batteries or a supercapacitor. The only emission from the bus is ...

Description

In 2018, Alexander Dennis launched the Enviro400EV in partnership with

, based on the Enviro400 City body and built on a BYD chassis. It is the second battery electric bus model from Alexander Dennis, following 2016's launch of the

single deck A single-decker bus or rigid is a bus that has a single deck for passengers. Normally the use of the term ''single-decker'' refers to a standard two-axled rigid bus, in direct contrast to the use of the term double-decker bus, which is essen ...

Enviro200EV, also produced in partnership with BYD. Initially, the first 10.9 metre Enviro400EVs first entered service with

Transport for London Transport for London (TfL) is a local government body responsible for most of the transport network in London, United Kingdom. TfL is the successor organization of the London Passenger Transport Board, which was established in 1933, and His ...

(TfL) operator

Metroline Metroline is a bus operator operating primarily in Greater London and partially in Berkshire, Buckinghamshire and Hertfordshire. It is a subsidiary of ComfortDelGro and operates bus services for London Buses under contract to Transport for Lon ...

on route 43 in 2019, followed by a shorter 10.3 metre variant launched in 2021. Alexander Dennis added to the EV range by introducing the Enviro400FCEV fuel cell bus in 2021, with the first completed example of the type being shown at the 2022 Euro Bus Expo. The Enviro400FCEV can be equipped with either a 45 kW or 60 kW Ballard FCmove-HD hydrogen cell as well as a 30 kWh electric reserve battery from Impact Clean Power Technologies, and the Enviro400FCEV has a maximum power output of 350 kWh provided by the Voith Electrical Drive System, offering a maximum range of . A second-generation Enviro400EV, featuring a newly restyled exterior and driver's cab, a new

Voith The Voith Group is a global technology company. With its broad portfolio of systems, products, services and digital applications, Voith trades in the markets of energy, paper, raw materials and transport. Founded in 1867, Voith today has aroun ...

driveline with a 410 kW peak power output, as well as options for either 472kWh or 354kWh

NMC NMC may refer to: Education Institutions * National Music Conservatory, Amman, Jordan * Nehru Memorial College, Sullia, Sullia, Karnataka, India * New Method College, a defunct secondary school in Hong Kong * Northern Marianas College, US Maria ...

batteries repositioned further towards the front of the bus, was announced by Alexander Dennis in November 2022, with the first complete bus unveiled in November 2023. An open top variant was also announced upon the launch of the second-generation Enviro400EV, while a variant built to TfL specification, offered with 14 year or warranty that allowed the buses to be used for two consecutive TfL bus contracts without requiring battery replacement, was revealed in August 2024.

Operators

First generation (2018-2024)

BYD D8UR Enviro400EV City

Large numbers of first-generation Enviro400EVs on BYD chassis have entered service with London's bus operators for TfL bus services across the city. Customers include

Go-Ahead London Go-Ahead London is a major bus operator in Greater London. The name first appeared in August 2008, before which the company had traded under separate names and brands. It is currently (as of April 2025) the largest bus operator in Greater Londo ...

, who alone have ordered 169 of the type for delivery throughout 2023,

RATP Dev Transit London RATP Dev Transit London was a bus operator owned by RATP Dev in London, England. It owned London Sovereign, London United and London Transit. It commenced on 11 December 2021 as a joint venture between RATP Dev and Kelsian Group. In September 2 ...

Stagecoach London Stagecoach London is a major bus operator in Greater London. It is a subsidiary of Stagecoach and operates services under contract to Transport for London mostly in East and South East London, as well as some services running into Central Londo ...

and

Abellio London Transport UK London Bus, formerly Abellio London, is a bus company operating services under contract to Transport for London in Greater London, England. History The origins of Transport UK London Bus can be traced back to June 1998, when Nat ...

. Ten of Stagecoach London's Enviro400EVs were used to shuttle delegates and world leaders at the

2021 United Nations Climate Change Conference The 2021 United Nations Climate Change Conference, more commonly referred to as COP26, was the 26th United Nations Climate Change conference, held at the SEC Centre in Glasgow, Scotland Scotland is a Countries of the United Kingdom, coun ...

Glasgow Glasgow is the Cities of Scotland, most populous city in Scotland, located on the banks of the River Clyde in Strathclyde, west central Scotland. It is the List of cities in the United Kingdom, third-most-populous city in the United Kingdom ...

prior to entering London service, while a batch of Abellio Enviro400EVs operating on route 63 were delivered with enhanced interiors specified under TfL's Future Bus project. Go-Ahead London also took delivery of eighteen Enviro400EVs fitted with

pantograph A pantograph (, from their original use for copying writing) is a Linkage (mechanical), mechanical linkage connected in a manner based on parallelograms so that the movement of one pen, in tracing an image, produces identical movements in a se ...

chargers for service on route 132 in 2021.

National Express West Midlands National Express West Midlands (NXWM) is bus operator in the West Midlands (county), West Midlands of England. It is a subsidiary of Mobico Group (formerly National Express Group) and is the largest bus operator in the region, as well as one of ...

and

National Express Coventry National Express Coventry is a bus operator providing services in Coventry. It is a subsidiary of Mobico Group operating on the operators licence of National Express West Midlands. History In October 1986, the bus operations of the West Midla ...

are also major operators of first-generation Enviro400EVs, with its first 19 entering service in

Birmingham Birmingham ( ) is a City status in the United Kingdom, city and metropolitan borough in the metropolitan county of West Midlands (county), West Midlands, within the wider West Midlands (region), West Midlands region, in England. It is the Lis ...

in July 2020 and an additional 10 arriving at

Coventry Coventry ( or rarely ) is a City status in the United Kingdom, cathedral city and metropolitan borough in the West Midlands (county), West Midlands county, in England, on the River Sherbourne. Coventry had been a large settlement for centurie ...

later in the year. National Express Coventry began taking delivery of an order of 130 Enviro400EVs in late 2022 as part of a plan for Coventry to have the first all-electric bus fleet in a UK city, with the completion of the order in September 2023 converting the National Express Coventry fleet to 80% zero-emission vehicles. A further 170 Enviro400EVs were delivered to National Express West Midlands in late 2024, taking National Express' total fleet of first-generation Enviro400EVs in the West Midlands to 329. National Express Transport Solutions, the tour coaching arm of the National Express Group, also took delivery of four Enviro400EVs in May 2022 for tourist shuttle services to the

Warner Bros. Studios, Leavesden Warner Bros. Studios Leavesden is an Film studio, studio complex in Leavesden, Hertfordshire, Leavesden in Watford, Hertfordshire, in the East of England. Formerly known as Leavesden Film Studios and still colloquially known as Leavesden Studio ...

Stagecoach Manchester Stagecoach ManchesterCompanies House extract company no 2818654

took delivery of 32 Enviro400EVs in early 2020, which were allocated to the

Sharston Sharston is an area of Wythenshawe, south Manchester, England. The population at the 2011 census was 16,754. History Built on former farming land (as was most of Wythenshawe when the estate was first being built in the 1920s), the area was i ...

depot for service in South Manchester. In addition,

Stagecoach in Cambridge Stagecoach East is a bus operator providing local and regional services across the East of England, operating in the counties of Bedfordshire and Cambridgeshire. The company is a subsidiary of the Stagecoach Group and is headquartered and regist ...

received two in February 2020 on the

Cambridge Cambridge ( ) is a List of cities in the United Kingdom, city and non-metropolitan district in the county of Cambridgeshire, England. It is the county town of Cambridgeshire and is located on the River Cam, north of London. As of the 2021 Unit ...

Citi 6 service. 22 Enviro400EVs were also delivered to

Stagecoach Bluebird Stagecoach Bluebird (also known by its legal operating name Bluebird Buses Ltd, and formerly Northern Scottish Omnibuses Ltd) is a Scottish bus company which operates bus services in the areas of Aberdeen, Aberdeenshire and Moray. It is a su ...

for service in

Aberdeen Aberdeen ( ; ; ) is a port city in North East Scotland, and is the List of towns and cities in Scotland by population, third most populous Cities of Scotland, Scottish city. Historically, Aberdeen was within the historic county of Aberdeensh ...

in April 2022, which were joined by 13 more in 2023;

Stagecoach West Scotland Stagecoach West Scotland is an operating region of Stagecoach UK Bus, comprising Western Buses Ltd based in Ayr, Scotland. History Stagecoach arrived in the west of Scotland when it purchased Western Scottish Omnibuses Ltd of Kilmarnoc ...

also received two Enviro400EVs for service in

Ayrshire Ayrshire (, ) is a Counties of Scotland, historic county and registration county, in south-west Scotland, located on the shores of the Firth of Clyde. The lieutenancy areas of Scotland, lieutenancy area of Ayrshire and Arran covers the entirety ...

in this same order.

First Leeds First West Yorkshire operates both local and regional bus services in West Yorkshire, England. It is a subsidiary of the FirstGroup, and is made up of three sub-division brands: First Bradford, First Halifax, Calder Valley & Huddersfield and Fir ...

ordered five Enviro400EVs for the Stourton Park & Ride, which entered service with the opening of the site in mid-2021, while

First Glasgow First Glasgow is the largest bus company serving the Greater Glasgow area in Scotland. It is a subsidiary of FirstGroup. The company operates within the area covered by the Strathclyde Partnership for Transport, a public body responsible for h ...

also ordered 91 Enviro400EVs alongside 22 Enviro200EVs in 2021. Delivery of the first batches of these buses began following the COP26 conference. Four Enviro400EVs were delivered to

Lothian Buses Lothian Buses is a major bus operator based in Edinburgh, Scotland. It is the largest municipal bus company in the United Kingdom: the City of Edinburgh Council (through Transport for Edinburgh) owns 91%, Midlothian Council 5%, East Lothia ...

in March 2021 with branding advertising

Scottish Power Scottish Power Limited, trading as ScottishPower, is a vertically integrated energy company based in Glasgow, Scotland. It is a subsidiary of Spanish utility firm Iberdrola. ScottishPower is the distribution network operator for Central an ...

, who helped to fund Lothian's order for the buses, and 12 Enviro400EVs were delivered to

Xplore Dundee Xplore Dundee is a bus operator based in Dundee, Scotland, operating services mainly within the city. The operator also runs a service to Edinburgh Airport. It is a subsidiary of the McGill's Group. History The company has its origins in the D ...

, entering service in early 2022.

Transport for Greater Manchester Transport for Greater Manchester (TfGM) is a local government body responsible for co-ordinating transport services throughout Greater Manchester in North West England. It is an executive arm of the Greater Manchester Combined Authority (GMCA), ...

ordered 100 Enviro400EVs in 2022 for use on its franchised '

Bee Network The Bee Network is an integrated transport network for Greater Manchester, comprising bus, tram, cycling and walking routes. Transport for Greater Manchester (TfGM) is expected to have commuter rail services joining the network in 2028. Initial ...

' bus services, which commenced operations in September 2023; the first 50 buses began to be delivered to

Go North West Go North West is a bus operator in Greater Manchester, England. It is a subsidiary of the Go-Ahead Group, operating franchised Bee Network bus services on contract to Transport for Greater Manchester. History Go North West commenced operat ...

for Bee Network services in

Bolton Bolton ( , locally ) is a town in Greater Manchester in England. In the foothills of the West Pennine Moors, Bolton is between Manchester, Blackburn, Wigan, Bury, Greater Manchester, Bury and Salford. It is surrounded by several towns and vill ...

in June 2023, and the remaining 50 entered service with Stagecoach Manchester in

Oldham Oldham is a town in Greater Manchester, England. It lies amongst the Pennines on elevated ground between the rivers River Irk, Irk and River Medlock, Medlock, southeast of Rochdale, and northeast of Manchester. It is the administrative cent ...

from March 2024.

Enviro400FCEV City

Twenty Enviro400FCEVs were ordered by the

Liverpool City Region Combined Authority The Liverpool City Region Combined Authority (LCRCA) is the combined authority of the Liverpool City Region in England. Its jurisdiction includes the City of Liverpool local authority area, the Metropolitan Boroughs of Knowsley, St Helens, S ...

for use on contract to both

Stagecoach Merseyside and South Lancashire Stagecoach Merseyside and South Lancashire is a major operator of bus services in North West England. It is a subsidiary of the Stagecoach Group and is headquartered in Liverpool. History Stagecoach Merseyside and South Lancashire can trace i ...

and Arriva Merseyside. The "publicly owned" hydrogen buses are branded for

Liverpool Liverpool is a port City status in the United Kingdom, city and metropolitan borough in Merseyside, England. It is situated on the eastern side of the River Mersey, Mersey Estuary, near the Irish Sea, north-west of London. With a population ...

's MetroBus network and operate on service 10A, Liverpool's busiest bus route which connects the city with St Helens via Knowsley. The first bus from this order was completed in November 2022, and the first buses started entering service with Arriva in May 2023. Issues with the supply of green hydrogen fuel meant that between 2023 and early 2024, most of Arriva's Enviro400FCEVs were non-operational, however combined with both the finding of a stable supply of green hydrogen and a battery refit, the fleet of 20 Enviro400FCEVs were set to begin re-entering service from mid-2024.

Second generation (2023-present)

The Stagecoach Group were the first operator to order and take delivery of the second-generation Enviro400EV, taking delivery of the first of 55 Enviro400EVs for

Stagecoach West Stagecoach West is a bus operator providing services in Gloucestershire, Bristol, Swindon, Oxfordshire, Wiltshire, North Somerset and Herefordshire, in the West of England, and Monmouthshire in the South-East of Wales. The company is a subsidia ...

Oxford Oxford () is a City status in the United Kingdom, cathedral city and non-metropolitan district in Oxfordshire, England, of which it is the county town. The city is home to the University of Oxford, the List of oldest universities in continuou ...

depot in March 2024, branded as 'electro' buses for use in the Oxford SmartZone. A further 180 were ordered by the group for delivery between 2025 and 2026, intended for Stagecoach subsidiaries receiving central government funding from the Zero-Emission Regional Bus Areas (ZEBRA2) scheme, with 48 of these to be delivered to

Stagecoach South West Stagecoach South West is a bus operator providing services in Devon and East Cornwall along with coach services to Bristol. It is a subsidiary of Stagecoach. History Devon General The Devon General Omnibus and Touring Company commenced opera ...

. In London, the first 17 second-generation Enviro400EVs built to TfL specification were ordered by Stagecoach London in July 2024 for delivery in early 2025.

Arriva London Arriva London is a bus operator operating primarily in Greater London and partially in Essex, Hertfordshire, Kent and Surrey. It is a subsidiary of Arriva UK Bus and operates services for London Buses under contract to Transport for London. Oper ...

took delivery of 30 Enviro400EVs across two batches between March and May 2025, the first 12 of which are branded for use on

London Superloop Superloop is an limited-stop, express bus network in London, England, that forms part of the London Buses network and connects Outer London town centres, railway stations and transport hubs. Orbital express bus routes were proposed in 2008 by May ...

route SL6, with the remaining 18 due for conventional TfL service on route 196. In February 2025, it was announced that the

Liverpool City Region The Liverpool City Region is a combined authority area in North West England. It has six council areas: the five metropolitan boroughs of Merseyside (Liverpool, Metropolitan Borough of Knowsley, Knowsley, Metropolitan Borough of St Helens, St H ...

Metro Metro may refer to: Geography * Metro City (Indonesia), a city in Indonesia * A metropolitan area, the populated region including and surrounding an urban center Public transport * Rapid transit, a passenger railway in an urban area with high ...

bus network is to take delivery of 58 Enviro400EVs.

Transdev Blazefield Transdev Blazefield is a bus group, which operates local and regional bus services across Greater Manchester, Lancashire, North Yorkshire and West Yorkshire, England. Formed in August 1991, the group has been a subsidiary of French-based operato ...

Harrogate Harrogate ( ) is a spa town and civil parish in the North Yorkshire District, district and North Yorkshire, county of North Yorkshire, England. Historic counties of England, Historically in the West Riding of Yorkshire, the town is a tourist de ...

subsidiary is to take delivery of 19 Enviro400EVs equipped with pantograph chargers for use on the 36 service between

Ripon Ripon () is a cathedral city and civil parish in North Yorkshire, England. The city is located at the confluence of two tributaries of the River Ure, the Laver and Skell. Within the boundaries of the historic West Riding of Yorkshire, the ...

and

Leeds Leeds is a city in West Yorkshire, England. It is the largest settlement in Yorkshire and the administrative centre of the City of Leeds Metropolitan Borough, which is the second most populous district in the United Kingdom. It is built aro ...

from September 2024, with the first bus from the order delivered to the company in June 2024.

Reading Buses Reading Transport Limited, trading as Reading Buses, is an English Municipal bus company, municipal bus operator owned by Reading Borough Council, serving the towns of Reading, Berkshire, Reading, Bracknell, Newbury, Berkshire, Newbury, Slough, ...

is to take delivery of 24 Enviro400EVs to replace biogas double-deckers on its Purple 17 and Claret 21 services, the latter serving the

University of Reading The University of Reading is a public research university in Reading, Berkshire, England. It was founded in 1892 as the University Extension College, Reading, an extension college of Christchurch College, Oxford, and became University College, ...

, in June 2025 as part of a 53-vehicle order for Alexander Dennis buses placed by the operator. An additional order for eight more Enviro400EVs will see the type introduced on the Yellow 26 upon delivery during 2026.

References

External links

Enviro400EV product descriptions

Enviro400FCEV product descriptions
{{Alexander Dennis Enviro400EV Double-decker buses Low-floor buses Vehicles introduced in 2018 Battery electric buses Fuel cell buses