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Solar cooling can end the bad loop, where the “urban heat island” effect increases the demand for cooling causing additional heat outside...



I suggest using solar cooling to stop the bad loop, where the “urban heat island” effect increases the demand for cooling causing additional heat outside, causing an increased need for cooling...

Solar air conditioning uses an old & established form of refrigeration called absorption refrigeration. It uses 2 different chemicals in a liquid solution (usually water and ammonia or lithium bromide). When the heat from a solar collector heats the concentrated solution, some of the working fluid evaporates (ammonia or  water). This evaporation process absorbs heat from its surroundings, cooling them down. The diluted fluid is cooled using a radiator or similar arrangement and  absorb the working fluid again, whereupon the cycle is repeated. 

This proposal takes its inspiration from the demonstration project “Solar Cooling for Industry and Commerce in Jordan” which aims to demonstrate feasibility and suitability of solar power for refrigeration in the region:

After the pilot project has been successfully implemented, it should become possible to apply the technology to meet all large commercial air conditioning needs in Jordan, assuming local conditions allow.

It should be noted that this pilot project is just one of many similar projects using solar cooling. Co-operation with a project in a middle-income country, would though bring additional benefits. A cooperation like this would show to all involved parties that we are all in the same boat regarding climate change, building up trust that we need to solve this great problem treating all humankind regardless of country or belief. Thus, I suggest that the The City of Cambridge should suggest co-operation with this project at that stage. Acquiring cooling technology that would not further warm the heat island would be just one although large benefit. 

This technology can be applied to all areas of Cambridge, although its benefits would be largest in the warmest areas. Thus, anyone of these could be used as a pilot area.






Category of the action


Who will take these actions?

Optimally, the The City of Cambridge would take the leading role in this project, working with building owners, building companies and individual home owners.

Potential partners in the project could be the local technology partner, Millennium Energy Industries (MEI) and Technical University in Berlin who has  developed the absorption chiller installed at the two demonstration sites - the German Jordan University (GJU) and Petra Guest House. Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) and Jordanian Ministry of the Environment and the Jordanian Ministry for Energy and Mineral Resource.



What are other key benefits?

- Technology transfer

- Trust building

Due to the law of conservation of energy stating that energy can be neither created nor be destroyed,the heat of the buildings cooled will be released outside the buildings, unless this heat is piped away and stored to be used in periods when additional heating is needed. This would add another benefit to this project, a diminished need for heating energy in the winter time. 

On possible storage for this heat could be the Fresh Pond reservoir, although its possible effects on the drinking water should be examined to avoid surprises. This stored energy can then be used for heating, by reversing the heat pumps in the winter time. 

This technology can be applied to all areas of Cambridge, although its benefits would be largest in the warmest areas.According to the heat island maps, one of the warmest areas is north of the Fresh pond, thus I would suggest this area to be used as a pilot area.  



What are the proposal’s costs?

The characteristic of solar cooling technology is small investment costs, long life time and low maintenance costs.

Adding heat storage to be used for heating purposes during winter time, would cause large upfront costs, but would provide savings in the long run outweighing the initial costs manifold.

One possible way to deal with the upfront costs, is to enlist an Energy service company to make the initial investments. It would then get is payback as a share of the value of the saved energy. 

Time line

This is existing technology, so it can be taken into use in a relatively short time. 

Related proposals

Have some relation to projects aiming at increasing reflectivity, and proposals using green plants for cooling, the all looking at the sun, hopefully not staring.