Boston Global Investors' proposal for a 1.05 million-square-foot development on the site of several South Boston parking lots owned by the Massachusetts Convention Center Authority. Image courtesy of CBT Architects

A re-run of an RFP process for a clutch of parking lots next to the Boston Convention and Exhibition Center in South Boston didn’t produce any additional bids, but Boston Global Investors and Cronin Development don’t appear to have scaled back their ambitions for the 6-acre site.

The Massachusetts Convention Center Authority is seeking developers to turn land along D Street it originally took in 2012 and 2013 during the construction process for the BCEC into activity-generators for the convention center’s neighborhood and adjoining hotels under a 99-year ground lease. An earlier version of the RFP process this spring was cancelled after South Boston elected officials publicly attacked the proposals, saying if the MCCA wasn’t going to develop the properties into hotels or support facilities for the convention center, they should be returned to the previous owners.

The latest version of the RFP only called for hotel, office, lab or other commercial space despite concern from some quarters that housing should also be included. The RFP also stipulated developments need to include 50,000 square feet of space for the MCCA’s offices.

According to a website Cronin set up to showcase its three-phase development proposal to the public, its plans have been scaled back slightly, to 1.6 million square feet, and anchored by 1.32 million square feet of lab and office space for life science tenants. Cronin’s bid was designed by architecture firm Sasaki and women-owned design firms UX Architecture Studio and Verdant Landscape Architecture.

Renderings show three distinct phases. First, a pair of office-lab buildings would rise over a mass timber podium on in the middle of the site along D Street just south of the Element Boston hotel, including an 8,000 square feet of not-for-profit gallery space dedicated to artists of color, a 25,000-square-foot public events space, a 30,000-square-foot food hall featuring women- and minority-owned vendors and an 8,000-square-foot space to give the historically Black Pensole Lewis College of Business & Design an outpost in Boston to train future designers in the region’s footwear industries. A “mobility hub” included in this phase would include “future infrastructure” for electrically-powered flying taxis and a stop for an existing shuttle service between Roxbury’s Nubian Square and the Seaport District.

The second phase, separated from the first by a 2.75-acre public park area and children’s playground, would include more lab space, a 7,500-square-foot daycare facility, an 8,000-square-foot community health center, and a 34,000-square-foot grocery store. The third phase, a 750,000-square-foot tower rising from a secondary part of the development site between Butler and E streets just behind the Aloft Boston hotel, would include a 40,000-square-foot, Black-owned film studio.

Cronin Development’s proposal for a 1.6 million-square-foot development on the site of several South Boston parking lots owned by the Massachusetts Convention Center Authority. Image courtesy of Sasaki

BGI’s plan totals 1.05 million square feet and would rise in two phases. The first phase surrounds a 1.5-acre public park and playground fronted with ground-floor retail: a 350,000-square-foot office-lab building, a 14-story hotel with between 250 and 300 rooms, a 60,000-square-foot grocery store located partly underground and a 30,000-square-foot community building that could host a branch of the Boston Public Library or other community space, along with backup batteries for the site and a complex energy and heat recovery system that BGI Vice President John B. Hynes IV said in an interview would play a major role in helping get the entire project to net zero carbon emissions.

“We can recapture and reuse so much of that wasted heating and cooling [generated by the grocery store and lab space] in the hotel above,” he said, adding that locating the grocery space underground – space it must excavate anyway to provide RFP-mandated parking and deal with existing site contamination – will help BGI subsidize the store’s rent and allow it to lure in a lower-priced store like Market Basket.

To help achieve its sustainability goals, Hynes said, the development team was including solar panels on most roofs and investigating whether or not a geothermal well field was possible on-site. In addition, the hotel portion of the first phase and the library building would be built out of mass timber instead of traditional steel and concrete, while the lab buildings would be built lighter than most speculative lab construction, with provision to add reinforcements later should a tenant need it.

A second phase, on the more northern parcel behind the Aloft hotel would host 450,000 square feet of life science space including a 40,000-square-foot podium designed for small-scale biomanufacturing, where the building’s tenant could prototype drugs during the research process.

“We provided a nice space because down the road we think there’ll be a need. Other lab buildings in the area just don’t offer it,” he said, noting that only nearby Vertex Pharmaceuticals has that capability thanks to a small manufacturing plant in the Flynn Marine Park near its Fan Pier headquarters.

The BGI proposal is designed by CBT, EMBARC Buro Hapold and woman-owned landscape architecture firm Crowley Cottrell.

Both development teams include substantial minority ownership. The Cronin project is 30 percent-owned by minority investors, while the BGI development team is 64 percent-owned by a group of five minority investment firms, including RISE and BGI’s partners on the under-construction 10 World Trade lab building, Bastion and Cogsville Group.