Adaptive traffic signals



Source: Mashable


Sustainability area: Safety, Energy and Health

Cities have a hard time dealing with congestion. It impacts GHG emission, air quality and energy consumption.  Adaptive traffic signals enable the city to adapt their traffic lights automatically based on real data (how many cars, accidents, pedestrian crossing).

Traffic is regulated based on actual road usage and habits. Thanks to sensors and camera, companies such as KLD developed algorithms that learn from patterns and can adapt or redirect traffic.

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Stakholders: City officials


Conduct a research on the cities that have the most pressing problmes related to congestion

Find areas in those cities where city official will be able to test the technology (enough traffic but not too much, and be careful to not use an area with too many pedestrians)

Record data before the technology is implemented and after it is inplace to compare and follow the progress achieved




Salt Storage

  1. Sustainability Problem: Renewable Energy Storage
    • There is a mismatch between when renewable energy is available (solar – during a sunny day, and wind – intermittently) and when energy is needed (all the time). Storage allows renewable energy to be used at any point in time, eliminating the need for “peaker plants” which emit large amounts of CO2 relative to ordinary power plants that run when demand is larger than the renewable energy supply. Storage will enable the scaling of renewables and a faster transition away from coal and fossil fuels.unnamed.png
  2. Technology:
    • Alphabet’s research lab X is working on a new energy storage technology called Malta. Malta works by storing wind and solar power in giant vats of molten salt and antifreeze, instead of lithium-ion batteries.  This technology is supposed to last for longer periods of time and be cheaper than the giant lithium-ion batteries currently available.
    • The technology works by converting wind and solar power to thermal energy. Heat is stored in molten salt, and cold is stored in a vat of liquid antifreeze solution. When the power is needed, the hot and cold energy are converted back into electricity by a heat engine.
    • The materials needed for thermal energy storage are cheaper and more abundant than this needed for batteries  — steel tanks, salt, and antifreeze — meaning this technology has the potential to be much cheaper than batteries. The company says its Malta technology may be recharged thousands of times and last for up to 40 years, several times longer than today’s batteries.
  3. Stakeholders:
    • Renewable energy producers
    • Utility companies
    • Regulators
    • Energy customers
    • Energy system designers and manufacturers
  4. Deployment
    1. Commercial viability test – the technology is still in the design phase.
    2. First commercial contract – partnering with a city that has committed to 100% renewable energy may be good place to start
    3. Work with utilities and regulators to enable the adoption of their technology across the grid.


Storing clean energy in salt isn’t as crazy as it sounds