These start-ups are making the world's cities more sustainable

Cities are home to a growing majority of the world’s population and account for more than 80% of the global GDP. Yet, despite occupying only 3% of the world’s land, cities account for two-thirds of the global energy demand and 70% of CO2 emissions.

The city of San Francisco in California has a long history of environmental leadership, between 1990 and 2020, the city’s carbon footprint was reduced by 48%, while the population grew by 21% and GDP increased by 194%. Meanwhile, almost half of San Francisco’s citywide emissions come from buildings and, over the current decade, the city is expected to grow its households by 82,000 units. By driving urban sustainability efforts to modify existing spaces to reduce embodied carbon and operational emissions, San Francisco hopes to become a role model for green cities.

In recognition of this, in June 2023, UpLink launched its first place-based Challenge aimed at sourcing sustainable buildings and green and blue infrastructure technology innovators with a commitment to being located and deployed in San Francisco. Each start-up had to be committed to addressing the UN Sustainable Development Goals (SDG), including SDG 11 for Sustainable Cities and Communities and be committed to being based in downtown San Francisco to help revitalize the area.

The Challenge was funded by Deloitte and Salesforce and supported by Citi, the San Francisco Chamber of Commerce, the City and County of San Francisco and 20 other local ecosystem partners. Top Innovators will benefit from access to a suite of resources to help deploy their solutions, introductions to key stakeholders, potential funders, experts and advisory services, and a $1 million grant from Deloitte to be distributed among the Top Innovators to help them build and scale their solutions.

This place-based Challenge directs resources from the Forum’s global partners and local collaborators towards a crop of innovators. The purpose is to foster a new sustainability innovation hub for San Francisco that is supported by an emerging local coalition of stakeholders across the public, private and non-profit sectors. This new local sustainability innovation hub is a partner of the new Alliance for Urban Innovation, which works to form a global network of innovation hubs to amplify learning and successes.

After sourcing submissions over two months, experts reviewed 144 solutions and finally selected a cohort of 14 Top Innovators, half from the San Francisco Bay Area and the other half from around the world, who each now have an opportunity to scale their sustainability impact.

Here are all 14 of the UpLink Yes San Francisco, Urban Sustainability challenge winners:

Rainstick has created a circular shower system that saves 80% of water and energy while doubling the water flow rate. It aims to reduce people’s water needs to 50 litres or 13 gallons of water per person per day without compromising their experience.

Babyloncreates remotely managed indoor vertical farms that give businesses and communities a convenient supply of ultra-fresh produce. The BabylonIQ software platform remotely manages a network of modular vertical farming systems to make sustainable agriculture much more accessible.

Zauben combines green roofs with solar panels and hydroponics, which absorb 10 times more water than ordinary green roofs and are 66% lighter. This innovative system enables versatile installation on a variety of building types.

Urban Machine uses robots to collect and recycle waste wood. It recovers wood from demolition projects by removing nails with an AI-powered pincer. It enables businesses to reuse wood from their existing properties or sell on the reclaimed wood for new projects.

Washbox is a closed-loop system for washing tools and construction equipment, cutting water use while keeping harmful chemicals out of the environment. Its cutting-edge hardware and proprietary software create a closed-loop system for capturing, recycling and eliminating liquid waste, conserving water and reducing environmental pollutants.

Sun Ice Energy stores solar power using a special material that freezes and melts according to when the energy is needed. Using its phase change material container design solution, it traps daylight energy and stores it in the floor and unit to maintain a desired latent temperature.

Butlr senses workplace occupancy through body heat and AI, letting businesses optimize their office planning and energy use without capturing any identities. It is already in use in the commercial real estate industry monitoring workplace usage and is being tested in senior living facilities.

Moxion's mobile power units can create a microgrid offering 15 hours of continuous power, boosting EV-charging infrastructure or supplying community events. Billed as the first fully-electric alternative to the fossil fuel generator, it provides emission-free power when and where it's needed.

Flower Turbines are quiet, bird-friendly wind-catchers with an innovative tulip shape, which are more attractive than traditional wind turbines. Available in three sizes, they start at lower wind speeds for smaller power needs, such as an e-bike charging station.

Taro AI makes monitoring tree health faster and cheaper for cities through AI, existing images and citizen contributions. By leveraging machine learning, computer vision and an engaged local community, this solution makes tree inventories and monitoring cheaper and faster for city governments.

It’s electric uses spare energy from buildings to power kerbside EV chargers. Its affordable network opens EVs to those who don’t have a driveway or garage to charge them in.

POSH Electric has created home battery packs for mobile clean power storage to support off-grid living and energy autonomy and replace harmful diesel generators. Its energy-efficient lithium-iron phosphate batteries are designed for use in camper vans, RVs and mobile homes.

374Water is a circular wastewater treatment system that uses high heat and pressure to oxidize sludge into clean, safe water and useful mineral salts. By processing all waste on-site for reuse, it eliminates sludge, fats, oils, grease and organic waste, while mitigating greenhouse gas emissions.

BluumBio is a biotech company that rapidly cleans air, soil and water using enzymes from fungi and tropical trees to remove industrial chemicals. Its solution uses a speeded-up version of nature to restore nature faster.