Environment
Fact-checked

At AllThingsNature, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What is Deep Water Cooling?

Michael Pollick
Michael Pollick
Michael Pollick
Michael Pollick

In an effort to reduce carbon emissions and the use of fossil fuels, some cities around the world have implemented a new type of air conditioning methodology known as deep water cooling. Deep water cooling takes advantage of the exceptionally cold water found far below the surface of many lakes and other bodies of water. This cold water, often only a few degrees above freezing, is drawn into the city's water system through large intake pipes, where some of it is diverted to water treatment plants for general consumption, but not all of it.

The exceptionally cold water passes through a series of parallel pipes, one containing the cold water destined for large air conditioning chiller and the other containing warm water returning from service. This system is closed, which means the untreated water used for air conditioning never mixes with the city's potable water supply. The cold water drawn from the deep water cooling pipe acts as a thermal sink or heat exchanger. The cold pipes absorb excess heat from the warm return pipes, making the water cold enough to cycle through the chillers again.

Deep water cooling requires piping the cold water into the existing municipal treatment system.
Deep water cooling requires piping the cold water into the existing municipal treatment system.

The frigid water used in a deep water cooling system does not become part of the closed coolant system itself. Its only purpose is to remove heat from the return pipes instead of using an expensive and environmentally damaging refrigeration system powered by electricity or fossil fuels. A city using deep water cooling technology can save significant amounts of money per year and also take advantage of a natural source of coolant for their swamp cooler air conditioning system.

Deep water cooling is not without its challenges, however. Many cities are not located close enough to a source of deep water to make intake pipes economically feasible, for example. Additional equipment must also be purchased and installed in order to introduce the cold water supply to an existing municipal water system.

The ideal city for a deep water cooling system would be a large metropolis near a significant body of water, such as Ontario, Canada. The city of Ontario does have three large intake pipes submerged in a deep section of Lake Ontario, and the cold water drawn from that depth does indeed work as a natural heat exchanger for the city's air conditioning system. Other cities are also studying the feasibility of deep water cooling, but the initial investment in equipment and the challenge of finding a suitable cold water source remains daunting.

Frequently Asked Questions

What is deep water cooling and how does it work?

Deep water cooling is an energy-efficient system for cooling buildings. It operates by pumping cold water from deep bodies of water, like lakes or oceans, where temperatures are consistently low. This cold water runs through a heat exchanger, absorbing heat from the building's air conditioning system, and then the warmed water is returned to the source at a depth where it won't affect the ecosystem.

What are the environmental benefits of deep water cooling?

Deep water cooling systems significantly reduce greenhouse gas emissions and energy consumption compared to traditional air conditioning. According to the Toronto-based Enwave's Deep Lake Water Cooling system, it reduces electricity usage by up to 90% for cooling purposes. This translates to a substantial decrease in fossil fuel reliance and a smaller carbon footprint for urban developments.

Where is deep water cooling currently being used?

Deep water cooling is used in various locations around the world, with notable examples including Toronto's Enwave system, which utilizes water from Lake Ontario, and Cornell University's system that uses Cayuga Lake. These systems serve as models for sustainable urban and campus cooling, showcasing the practical application of this technology in large-scale operations.

Is deep water cooling a cost-effective solution?

While the initial setup costs for deep water cooling can be high, the long-term savings on energy bills make it cost-effective over time. The system's low maintenance and operational costs, combined with its longevity and efficiency, result in significant savings. For instance, users of the Toronto system have reported substantial reductions in their cooling costs.

Can deep water cooling be used in any type of building?

Deep water cooling is versatile and can be adapted for various types of buildings, including commercial, residential, and industrial structures. However, its feasibility is primarily dependent on proximity to a suitable cold water source and the scale of the cooling demand. Retrofitting existing buildings can be challenging, but new constructions can integrate deep water cooling more easily.

How does deep water cooling impact the local ecosystem?

When properly designed, deep water cooling has minimal impact on local ecosystems. The intake and outflow of water are carefully managed to prevent thermal pollution and protect aquatic life. Systems are typically designed to draw and return water at depths that maintain natural temperature gradients, ensuring that the local marine environment remains undisturbed.

Michael Pollick
Michael Pollick

A regular AllThingsNature contributor, Michael enjoys doing research in order to satisfy his wide-ranging curiosity about a variety of arcane topics. Before becoming a professional writer, Michael worked as an English tutor, poet, voice-over artist, and DJ.

Learn more...
Michael Pollick
Michael Pollick

A regular AllThingsNature contributor, Michael enjoys doing research in order to satisfy his wide-ranging curiosity about a variety of arcane topics. Before becoming a professional writer, Michael worked as an English tutor, poet, voice-over artist, and DJ.

Learn more...

Discussion Comments

spasiba

I have also read that Cornell University is working on reducing traditional energy consumption, by replacing it with deep water cooling systems. The cold water used will be from a nearby lake.

The initial investment is very high, something like tens of millions of dollars. I imagine that it will repay itself in the long run.

anon32595

The city you refer to is Toronto which is in the province of Ontario, which is in the country of Canada.

Post your comments
Login:
Forgot password?
Register:
    • Deep water cooling requires piping the cold water into the existing municipal treatment system.
      By: chartcameraman
      Deep water cooling requires piping the cold water into the existing municipal treatment system.