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Local rivers, lakes and even ocean water can be used to reduce city water and electricity needs to cool urban buildings.



Currently urban buildings have a high demand for electricity and water to cool their interior spaces.  Studies have shown that buildings consume more energy and cause more green house gas (GHG) emmissions than any other source, including cars.  Building cooling is typically done with a decentralized cooling plant for each building, each of which requires electric power and water to remove building heat via a chilled water system with a refrigeration cycle (chillers & cooling towers).  A power plant uses river, lake, and ocean water to cool their systems before sending that power through transmission lines.  There are inefficiencies of about 50% at the source of generation and still more losses when transporting that energy via power lines to urban settings. 

An alternative to this is to eliminate these losses, both from the distant centralized power plant and the many decentralized cooling plants, by using local cooling sources such as rivers, lakes and ocean water.  This alternative would allow buildings to be provided with a centralized means to cool their buildings using nearby existing natural resources that are already acceptable to the federal and state EPA authorities having jurisdiction.  

Unlike industrial sites and power plants, the only change to the water used in this manner is the temperature.  The EPA and other agencies worldwide (such as the EU Water Framework Directive, River Boards Act in India, and State Environmental Protection Administration in China) recognize limits in water temperature discharge and amounts, all of which are well within normal building cooling temperatures. 

Category of the action

Urban adaptation

What actions do you propose?

Public-private partnership arrangements can be implemented to support projects of these types and magnitudes throughout most of the United States.  The city of Ithica, NY, with their lake source cooling for Cornel University as well as other buildings in the city, has paved the way many years ago.  Honolulu, HI and Toronto, Canada are also recent examples of how to gather support, funding, and follow through with implementation for urban environments. 

The first action would be to generate specific action plans through proposals to cities that have expressed interest via inter-city conferences.  This would be an outreach phase, to determine which the public entities would be open to such as solutions.  The initial funds from this program would be utilized to illustrate past projects with a history of performance.  Ithica, NY and Toronto, Canada have lake source cooling projects that support their downtown urban needs.  Honolulu, HI is implementing an ocean cooling solution that is underway; the project is expected to achieve significant savings on their scare water and fossil fuels (imported to generate electricity).   

The second action would be to draft schematic designs that show approximate scale of the projects to be undertaken.  These designs would be used to identify funding needs.  This phase could be supported by either initial city research projects or more broadly from research groups such as the National Science Foundation. The schematics would highlight the reliability of the designs to show that cooling failures are minimized while saving energy, reducing GHGs, and minimizing all of the costs associated with decentralized cooling plants. 

The third action would be to seek potential clients (developers, government agencies, and other building owners) to participate.  The economic viability to use this centralized cooling system would be emphasized. Part of this would be to show that each owner would not need to be concerned with maintaining and replacing their own expensive cooling plant equipment, and even regaining valuable building space.  Additionally the owners would not be limited as to the cooling plant capacity but would have the flexibility to use what they need and the scalability to increase their loads per customer needs and still keep the same reliability. With well defined plans, detailed economic and environmental benefits that are clearly articulated, and buildings that are looking to save water and energy, funding sources generally begin to appear to be part of such positive (economic and environmental) solutions. 

The fourth action is implementation - construction of the water source cooling means and routing of the water to the most dense urban areas for the clients. Utility companies and their consultants have experience with implementing such installations to be capable of reducing complications and cost overrun risks. 

Who will take these actions?

The first action is to be undertaken by our team.  The funding from Climate CoLab would be used to illustrate potential implementation at conferences and events meant for city officials and managers.  The funding would also then be used to follow up with interested parties to understand the level of interest, gage potential hurdles, and tailor the solutions for these factors. 

The second action would also be undertaken by our team to understand where further funding could be found and to develop the schematic designs needed for various scales of implementation. 

The third action would be the responsibility of the team as well as the public and private partners to educate and bring building owners to commit to using this new water cooling source. 

The fourth action would be overseen by our team by assembling general construction management firms to assume the risk for the construction costs and schedules.  Our team would act as the client's advocates and bring subject matter experts to advise from the beginning of construction to the final commissioning.

Where will these actions be taken?

The first action would take place at a number of conferences and events; upon receipt of the winning efforts here they will be disclosed. 

The second, third and fourth actions would be based on the cities interested in implementation. 

What are other key benefits?

As each city can reduce the energy used by many decentralized cooling plants that cause peak power needs, power plant transmission and production losses can be lowered.  Expensive additions to power plants, electrical capacity upgrades, and cooling plant replacements can be avoided.  Additionally, harmful and inefficient refrigerants used in decentralized cooling plants can be reduced dramatically where the solution is implemented. 

What are the proposal’s costs?

The initial costs (first action) would be for conference and event fees and their associated travel. Also meetings with city officials and managers would need to be conducted to understand budgetary constraints and overall environmental and energy savings goals to see if they align with this solution.  The total cost is in the range of US$20,000 to 50,000, depending on whether locations around the world express serious interest.

For action 2, with acceptance to proceed by a potential city, local loans can be established to begin schematic designs and economic viability.  US$200,000 is the likely minimum, which may require several funding sources to avoid higher risk loans.

Action 3 costs would be to support the time required to network and understand client needs and answer their questions.  Since this depends on the city and the typical pace of local authorities (as well as interfacing with state and federal groups), this can take a year or longer to establish city resolutions and push to the next action of undertaking the project.  US$2,000,000 approximate.

The construction of the actual project would have a wide range per city based on its location and project size.  Each city might have a cost of about US$3,000 to 5,000 per ton of cooling.  For example, a city may need about 30,000 tons of cooling at its core; with access to an adjacent river or waterway the construction cost may range from US$90 to 150 million.  This may be on par with an electrical system or power plant upgrade, but with much better efficiencies. 

Time line

The first phase (action) may require about a year to find and generate serious interest.   By showing past project success in other cities, it may be easier for a city to grasp the concepts than more tricky maneuvering of investment funds based on future energy savings. 

The second phase would be implemented within a 6-12 week period to determine viability.  While certain cities may show excellent promise, their economic status will be checked to determine whether they would need to stabilize or if their is potential to proceed. 

The third phase would likely be a year or longer to meet and get clients to commit to being part of the project.  The amount of assistance from the public officials and private investors can certainly decrease the amount of time needed.  Additionaly this time would be to assuage public fears about using water as a cooling source, as using water in such a manner is less damaging and much more efficient. 

The fourth phase, construction, could be between six months for a small, fast-track, design-build project or several years. 


Related proposals


Others available upon request.