KyotoCooling and CPI Passive Cooling – Simple But Effective | Chatsworth Products
We use cookies to personalize content and to analyze our traffic. You consent to cookies if you continue to use this website. To find out more or to disable cookies view our Privacy Policy. X

KyotoCooling and CPI Passive Cooling – Simple But Effective

(CPI Products, Environmental, Thermal Management) Permanent link

It seems to be pretty much impossible to browse data center websites or magazines without being inundated with the challenges of data center cooling and the myriad of solutions being touted. If a data center professional made a serious effort to be well-read on all the topics, I think the data center itself would suffer from lack of attention. Personally I prefer the most simple and effective approach to just about anything I do. If I’m able to employ these two criteria, then not only is my day more productive, but the end result will meet my satisfaction.

CPI’s approach to data center cooling is simple and effective. I know, I’m adding to the noise by saying so, but the claim is worth investigating if you want a solution that is capable of taking your existing cooling capabilities and making it go farther – so far that you will use less cooling and power to get the same (or better) results.

The way we do it is simple. Our line of ducted equipment cabinets completely separates hot exhaust air from the cool air in the room. CPI pioneered the “chimney” cabinet which uses a duct to funnel hot air into the drop ceiling where it can be returned to the cooling unit. No more hot spots. No more recirculation. This concept, called CPI Passive Cooling® Solutions, has been tested and proven. If you have not had the opportunity to see how Intel incorporated CPI’s ducted cabinets, watch the video.

Room Comparison 

Let’s take it one step farther and talk for a minute about KyotoCooling® – a cooling system that uses a rotary wheel type of condenser to cool data center air without using a compressor. A recent article written by Rakesh Dogra on the Data Center Journal Website concluded that KyotoCooling seems to be the best possible answer to data center cooling thus far. What does this have to do with CPI Passive Cooling? Both solutions work hand-in-hand. Dogra explains the Kyoto concept like this, “The solution works in such a way that the cold air which is used to cool the hot air inside the data center does not actually mix with it … there are two circuits of air which are physically separated …”.

KyotoCooling Wheel 

Even though CPI Passive Cooling does not rely on rotary wheel cooling, the end result is so effective that CPI is a regular presenter at KyotoCooling Seminars. The next series of seminars will be held December 1-2 and 3-4 in the Netherlands. Ian Seaton, CPI’s Technology Marketing Manager, will speak on “Maximum Cooling Efficiency with Hot and Cold Air Isolation at KyotoCooling: the Cooling Problem Solved”.

If the Netherlands is too much of a commitment, or if you have a question, contact us for more information by leaving a comment below or emailing Kim Ream, eMarketing Designer 

Posted by Kim Ream, eMarketing Designer at 03/28/2012 12:49:35 PM


How do you deal with high density racks?
Posted by: Loy Fraser at 11/15/2008 11:03 AM

Both solutions from KyotoCooling and Chatsworth Products deal quite effectively, depending on your definition of "high density racks." The KyotoCooling model is designed to accomodate densities up to 500 watts per square foot, which will transate into 15-20kW per cabinet, depending on how the space is utilized. These can be standard server racks either with a high % open mesh doors or without doors and the density is handled by the pressure difference maintained in front of the cabinets versus behind the cabinets. The front positive pressure is maintained by the make-up air source and the rear lower pressure is maintained by the pull of the re-circulation fans. Those densities can be further increased by deploying the CPI Passive Cooling ducted exhaust cabinets which maintain a negative pressure behind the servers up to 3600 CFM, which translates to 23kW up to over 40kW, depending on the type of server and the temeprature rise of the inlet air versus the outlet air. In general, KyotoCooling and Chatsworth Products Passive Cooling Solutions create quite hospitable environments for today's high density rack deployments.
Posted by: Ian Seaton at 11/17/2008 7:16 AM

I've been reading about Kyoto Cooling for many months now.

Any US installations? Why are all the tours in the Netherlands?

Can these systems be purchased in the US? From whom?
Posted by: Rex at 11/27/2008 1:50 PM

There are no US KyotoCooling installations yet, but there will be one in Montana in 2009 and there are a couple more on the way and several more under consideration. There are currently only four operating KyotoCooling data centers in the world and they are all located in the Netherlands, which is the reason why the tours and the open house conferences have all been in the Netherlands to date. Discussions are under way to create a US test data center, but there is not yet a project timeline on that initative.
I would add one further comment regarding the question of purchasing "these systems" in the U.S. The system is really a total engineered solution that needs to be developed in conjunction with a data center owners architect and mechanical engineering consultant. They key pieces that are not common off-the-shelf commodities for the time being can be purchased from KyotoCooling, International. In addition, a total system purchase would involve contracting with KyotoCooling or Uptime Technology to participate in key milestones with the architech and MEP to assure design intent is being executed.
Posted by: Ian Seaton at 12/2/2008 9:06 AM

I've been following the discussion with free cooling based on outside air in various articles. I havew two concerns however:
1) how is the humidity controlled? Very cold outside air is very dry and hot air can be very wet. Especially dry air can have cause static electricity in computing and networking equipment.

2) although servers can run at higher temps than say 21 C, they will start to consume more to create more airflow. Fans will speed up and use more electricity. This power supply is on UPS and hence craetes a near double impact on the real use.


Posted by: Marc Van den Wyngaert at 1/30/2009 5:34 AM

1. Humidity concerns always top discussion on free air cooling. First, since this blog chain has been mostly about KyotoCooling energy recovery wheel economization, I would point out that it is not a particularly serious concern since the actual exchange with outside air is less than 1/3 of 1% by volume as the heat exchange takes place through the revolving heat exchanger with separation between the data center and the outside world. In addition, in that environment, relative humidity can be controlled to a large extent merely by temperature modulation. As for traditional air-side economization, some form of relative humidity management is required. Fortunately, concerns about dry air and ESD are probably not founded. At this week's ASHRAE TC9.9 national meeting in Chicago, world-renowned ESD expert David Swenson delivered a very compelling paper on how low humidity is not a threat to our data centers. The basic premise was that if the equipment was properly grounded and otherwise prtoected, dry air would not cause an ESD threat and, conversely, if the equipmetn was not properly protected, moist air would not protect the equipent from ESD. While the resultant investigation proceeds now, there is still a low dew point spec in the ASHRAE 2008 Environmental Limits, but it is being defanged and high humidity is going to be where the concern resides and some form of ultrasonic control is typically going to be the most efficient.

2. Most servers will see their internal fans start to kick up and consume more power when the inlet temperature exceeds 77 degrees (25C), which means there is now a 3.6 degree window of extra fan energy consumption inside the new ASHRAE environmental limits. So first, you can drive your inlet temperature past that 21C (70F)without incurring any penalty from your server fans. Above 25C, you can start paying that penalty, and we all know how that is decidedly not a linear relationship between airlfow and energy and we will be the loser. However, you need to weigh that against the benefits of the higher temperatures, particularly if you are running free cooling. The proportional fan energy budget for a 1U server is much lower than it is for a typical blade center, so the first thing is to determine exactly what that is compared to the energy budget for the chiller plant, which can be 75% of the total cooling budget or 35% of the total data center energy budget, and then determine which is costing you more. I would say that you would normally expect the savings for not running the chiller plant to exceed the extra cost of running those server fans faster; however, if the only benefit you're looking to get from running your inlet temperatures higher is a chiller plant efficiency benefit of around 1% per degree, then the extra 3 degrees at the higher server fan levels is not likely to have a positive payback.
Posted by: Ian Seaton at 1/30/2009 3:12 PM

kindlly , can you send me more detailes about this system and it's pictures if there , and how can we have benefit of this system with air conditioning unit with detailes . thanks
Posted by: abdo at 3/17/2009 10:12 PM

If you are interested in receiving further information, please email me at so that I can get your email address. Thanks!
Posted by: Kim at 3/24/2009 5:51 AM

What is the power consumption for 300 KW unit?
Posted by: Bassm at 9/2/2009 12:57 PM

I'm intersted to know more about your operation in US/Canada.Is the installer ready to demonstrate the technology
Posted by: Duraid Al-Jailawi at 1/9/2010 5:15 AM

Interested in specifications of Kyoto system for data center being planned in Northern Wyoming.
Please have sales rep forward me data and info for review.
Posted by: ron patterson at 6/26/2010 7:58 PM


I do not have your contact info but the Wyoming CPI sales manager is Tom Cabral. You can call him at 602-361-7657 or email him at Or you can email me at
Posted by: Kim at 6/28/2010 6:17 AM

Leave a comment
Name (required)
Email (optional, not published)
Your URL (optional)

Note: Conversation is encouraged and expected. However, moderation of comments is necessary to prevent spam, personal attacks, profanity, or off-topic commentary. Comments related to specific product support or customer service issues will be addressed separately rather than posted here. Please email for assistance with these matters.

3/21/2019 7:44:01 PM