The Earls Court Development Company has unveiled plans to "bring back the wonder" to one of London's most famous, and most famously derelict, sites promising 7.35 million square feet of boundary-pushing sustainable development.

Home for more than a century to the capital's key international exhibition and events venue, the site has been flattened and derelict for eight years as an increasingly fraught breakdown in relations between local residents, politicians and landowners stalled progress on central London's biggest cleared development plot.

In 2019, a new consortium bought the land, which lies in the western part of Zone 1, the central transport area, promising to end the deadlock and get on with developing what has always been one of the capital's best connected sites. On paper it is also one of its most valuable, given its location bordering some of the most expensive homes in the country.

Three years on and the consortium is now ready to show off what it has been working on, with ECDC chief executive officer Rob Heasman telling CoStar News the site has created a "London jigsaw missing its final piece".

The location may be well-connected, with three tube stations leading into it and multiple bus stops, but unless you have been in a helicopter you are unlikely to have seen it in recent years, given it is blocked from view by various hoardings, houses, churches and transport depots.

Heasman and colleague and director of public affairs Rebecca Paczek are understandably keen to get visitors on site to show off what they have been formulating with a team bolstered half way through last year to include a list of senior advisers from across the capital. In November the final piece of the masterplanned site, the 15-acre Lillie Bridge Depot, was bought and added.

So who is behind the new development company? It launched with the acquisition of the site in 2019 and comprises a joint venture between UK investor and developer Delancey, on behalf of its client funds, and the Dutch pension fund manager APG, as well as Transport for London, a long-term landowner. It owns land straddling two London boroughs, the Royal Borough of Kensington and Chelsea, which oversees around 40%, and the London Borough of Hammersmith and Fulham, which oversees around 60%. Both authorities see it as critical to their economies, and it has also long been identified by the mayor of London as an Opportunity Area – or an area that will be important to deliver the homes and jobs the capital needs for the future.

So it's no surprise that the 40-acre site plans unveiled today are big and ambitious. Nevertheless they are decidedly less big and very different to the 11 million-square-foot, 77-acre Sir Terry Farrell-masterplanned proposals that previous developer Capco attempted to get off of the ground for the best part of the last decade. So what has changed and why are they going to have lift-off this time around?

At its peak the two Earls Court venues generated a £2 billion turnover a year for the capital's economy. But it had lost ground to other conference centres such as the Excel Centre in London's Royal Docks and the National Exhibition Centre in Birmingham when a decision to grant the famous buildings at the site a Certificate of Immunity from Listing – essentially allowing them to be demolished. This was so that owner Capco could bring forward what it promised would be Europe's "largest regeneration scheme", supported by then mayor of London Boris Johnson and the Hammersmith and Fulham administration.

The subsequent failure to get spades in the ground as rival projects at King's Cross Central, Stratford City and Battersea Power Station have taken shape has been a salutary reminder that changes in political leadership as well as passionate local opposition can scupper even the most powerfully endorsed developments.

Though it took another five years, the collapse of the plans was made inevitable by the 2014 change in the political make-up of Hammersmith and Fulham council. That saw a Conservative administration led by Boris Johnson's friend and supporter Stephen Greenhalgh, which had pushed for two major housing estates to be part of the development, voted out in favour of a hostile Labour Party that had made rethinking the inclusion of the West Kensington and Gibbs Green estates part of its manifesto.

By April 2019, as Capco sought to sell the site on to private developers while pursuing a demerger that split its Earls Court and central London Covent Garden holdings, an exasperated Hammersmith and Fulham council was rubberstamping plans to use a compulsory purchase order to buy part of the site from Capco and TfL at an estimated cost of £650 million.

Cabinet meeting papers published at the time wrote: “The project has completely stalled over the last six years, with only demolition of the exhibition centres taking place."

When the site did change hands, Delancey-APG and Hammersmith and Fulham wasted no time terminating the Conditional Land Sale Agreement with Capco and returning the land that included the West Kensington and Gibbs Green housing estates to the council.

Cllr Stephen Cowan, leader of the London Borough of Hammersmith and Fulham at the time, said: “Delancey gave me their word and stuck to it by ripping up the Conditional Land Sale Agreement, returning the two council estates and ending a 12-year-long nightmare for thousands of our residents."

Heasman says handing back the estates has been "critical" in progressing development.

"Saying they were not part of the plans was important as for many that had been toxic. We have really focused a lot on working with the community to discuss what we are doing on the estate. It has been important to bring in meanwhile uses during this period."

Heasman and Paczek say the fundamental reasons development of the site will be a success under the new ownership remain the same as before – the connectedness which means the often insurmountable cost of building in accessibility and infrastructure has been removed from day one.

A much bigger focus this time on space for the public and local community is no doubt influenced by previous owner Capco's bruising encounter with local residents over its plans.

The latest plans are for a more "inclusive and equitable piece" of city, Heasman says.

Capco's plans were for a principally high-end, high-density residential development that included up to 7,500 for-sale homes, principally at market rates, and two million square feet of offices, retail and leisure including two hotels.

The new plans still include a lot of homes – ultimately 4,500 – but the mix is more varied with ECDC proposing around 60% residential and 40% commercial, culture, community, and retail space.

The tenure of the housing will be more mixed too with homes for rent, for sale (including shared ownership), for students and for older people. These will cater for local need and target 35% affordable across all tenures, based on a median income agreed by the mayor of London.

And then there is a greater focus on a mix of commercial development. The partners say their plans will create "a destination for enterprise and economy" and a projected 15,000 jobs.

The development will, in part, be a research and development hub for "green tech", attracting businesses which are responding to the climate crisis, they say. There will be a "creative boulevard", described as a "new street to foster innovation on site by making space for research and development, alongside space for arts, performance, and music".

Connecting West Kensington Station in the north and Empress Place in the south, and running through the new Train Shed Square which repurposes the heritage train depot buildings, there will be a mix of smaller affordable spaces through to larger offices as well as an area for a food market

There will be space for company headquarters again, with a large-scale office pencilled in for the first phase on a gateway site fronting Warwick Road. There will also be co-working spaces and specialist office and research space, which could be centred around a new campus for start-ups.

There will be flexible spaces for education and training for institutions and there will be also be space set aside for "modern logistics" using the level changes on the site to make use of basement and below ground spaces for last-mile logistics.

The scheme will be built on only 40% of the site to leave a large swathe for public open space including a new park at the centre and a network of squares, streets, and gardens. The park will be larger than Trafalgar Square, and one quarter of the site is dedicated to fully accessible new squares, gardens and the park. A further fifth of the site will be used for tree-lined streets.

Phase one will be one of the largest London sites to come forward in recent years, with the consortium planning to seek investment partners shortly.

There will also be a focus on new venues for live music, comedy and shows. That will include a flexible venue for theatre, music, exhibitions and events and likely a gallery space, in addition to including public art within the open spaces.

A purpose-built facility will front on to the new Aisgill Gardens to create a cultural community hub. The team hopes the outside spaces will be home to "live events, impromptu rehearsals, busking and small performances".

Attractions hosted on site during the hiatus as plans are worked up have included the live entertainment company Underbelly's Underbelly Festival and the Lost Estate immersive theatre. A 30,000-square-foot temporary building is under construction at present to house a BBC Earth Experience featuring Seven Worlds One Planet narrated by Sir David Attenborough and a Skills Centre will open in the spring of 2023, beginning to offer training opportunities to local people.

Heasman says a decision to locate the Earls Court development business on the site has been "priceless".

"Being based locally has given us the ability to get to know the communities in which we are based, to understand the experiences of people who live, work and go to school here. We have used that to inform and shape the draft masterplan concepts which we are now presenting.”

An initial focus has been redeveloping a street of homes and workspaces leading into the site from West Brompton Tube station. That has included redeveloping homes at Empress Place and at the former Seven Stars pub for people on a low income and key workers. The consortium also developed creative workspace and studios in collaboration with Projekt, called Empress Studios.

Much has been learned from how the pandemic has changed attitudes to development and community engagement, Heasman says, meaning the masterplanning has focused on building in flexibility.

"We are looking at the future and the next 150 years for this site and the impacts of climate change in particular. We are using The Table area over the tunneling of the District line as new public realm joining the borough together with a strong east-west link," Heasman says, pointing out that this differs from Capco's proposals to have as many as 4,000 parking spaces beneath this part of the site.

Symbolically what was the old Capco marketing suite now houses a community centre and "an artists in residence" hub for local artists.

"The role of the masterplan is to build in flexibility and to enliven," Heasman adds. "We are taking the famous Earls Court steps now and retaining them to create a proper sense of arrival at a site that has been home to the Great Wheel, the Ideal Homes exhibition and the Brit Awards. It is a site with a rich role in London's history."

In the end Heasman says there will be more than 100 buildings with the tallest of these tapering upwards to the centre.

"It makes sense for the tallest of these to be in the centre at around 40 storeys. We want to work within the the constraints of the site, for instance the bordering with St Cuthbert's Church. There will be around four to five buildings over 30 storeys."

A big focus will be on low carbon development with Heasman saying the project will "push the boundaries for ESG development on all three different measures".

Paczek adds: "We have the potential to really make a difference to the people around here. We have an ambition to be a global exemplar of responsible, sustainable development, putting people’s health and well-being first.”

To that end the aspiration is for the development to incorporate what the partners are calling the first large scale zero-carbon energy sharing network in the UK, enabling local people to benefit from cost effective heat networks.

"Ultimately what we are doing is creating a place which reinstates 'wonder' in this incredible part of London," says Heasman.

One senses his battle to redevelop one of London's most prized sites is only just beginning.

The masterplan will "evolve" over the course of 2023 with a planning application due to be submitted by the end of the year. The first phase of development proposes 1,300 homes, the giant park and east-west connections, with work expected to begin in 2025.

The will be least one "signature" office building designed by ACME and fronting the entrance to the site on Warwick Road in Kensington and Chelsea.

Sheppard Robson with Serie Architects and dRMM will oversee the first phase in Hammersmith and Fulham.

Haworth Tompkins and Maccreanor Lavington will collaborate to bring forward the first homes in Kensington & Chelsea and a "significant cultural offer" at the heart of the site.

Artwork contributions from: Julia Lee, Jelena Schulz, Nicole Shih, Leslie Trejo