Data Centre Operations Blog

Risks Become Tangible

The Gulf of Mexico oil spill has a tangible $100b liability for BP (and 32 million Google hits for “Gulf of Mexico oil”). The Blow out Preventer (BOP) failed despite having a low catastrophic failure rate (4 tests failed in around 90000 tests). Even if we assumed the MTBF (mean time between failures) to be around 100 year, this is still a high risk of $100b per failure / 100 years/failure = $1b/year… Read More

Trigeneration or Free-Cooling

The data centre industry is immersed in an interesting innovation process in search of higher efficiencies. One idea is using trigeneration, where electricity is generated (via engine or turbine) and its residual heat is used as a heat source for an absorption chiller. For example, a car engine provides mechanical energy to move the car and waste heat for heating (radiator). Trigeneration systems tend to be more expensive and complex than traditional systems,.. Read More

The Gartner Data centre power and cooling technologies hype cycle

For those thinking of investing in new technologies for data centres, this is a must read document. It describes most technologies and concludes that mainly those related to fundamental issues of cooling and UPS as likely to survive the hype cycle. (Reproduced by courtesy of Gartner) As the applications of technologies are changing fast, this work should be updated when possible. It would be useful to explain the outcome differences between ‘on site.. Read More

The Age of Contained Air Managed Cooling

At DCD London November 2010 Neil Rassmussen has challenged the traditional raised floor cooling by referring to it as “the end of raised floor cooling”. Whilst I agree with the end of an era of “open air management” cooling systems (which mostly use raised floor cooling) I think we will still continue to see raised floor cooling designs and for valid reasons. I have been involved or am aware of recent designs that.. Read More

Cold air as a renewable source of cooling

Why not? Providing it is at a colder temperature than what we need to supply to IT equipment, it is cheaper than other renewable technologies (tidal, wind, solar, geothermal), it readily available in all the world, and it only has the embodied energy of the air handling units. Even if the temperature of the air is warm, unless it is saturated with water vapour, it just requires adiabatic cooling (using water) to bring.. Read More

“Human Unawareness” of Energy Saving Potential

While “human error” is responsible for most mission critical facilities failures, “human unawareness” is responsible for easily avoidable energy wastage in data centres. For most data centres 10-30% energy savings can be achieved with low investments. In a typical 1000m2 raised floor data centre, savings of hundreds of thousands of £, USD, Euros per year can be achieved with Return on Investments (ROI) under a year. Air management is normally the fundamental first.. Read More

“Managing Risk: The Human Element”

This is the title of an excellent book by Duffey and Saull, that analyses the space, nuclear, aviation, chemical and other industries and reports that 80% of all failures are down to human error. This correlates well with the Uptime Institute’s reports of approximately 70% of data centre failures attributed to human error. Duffey and Saull construct a human failure rate bath tub curve and explain the Universal Learning Curve as an exponential.. Read More

Air Performance

“I have 1200kW of CRAC units installed in a data centre designed to 1000kW of IT load which is currently loaded to 80%, so I should be OK”. Wrong, or at least you are not looking the right information. What is really missing is how much of that air cooled by CRAC units actually makes it to the IT equipment. The following diagram shows that approximately only 50% of the CRAC air actually.. Read More

Thermal runaway

Backup generators to start-up and power to be restored to the cooling systems before they restart. To overcome the high air temperatures entering IT equipment during this event, many new designs put CRAH fans and secondary chilled water pumps on UPS (so they are immune to a mains interruption) and may also include large chilled water storage tanks to provide cooling media inertia. The consensus amongst IT equipment manufacturers is a recommended server.. Read More

Compromising Commissioning

There is always pressure at the end of a project to reduce commissioning time. However, the interdependency dimensions of any project are financial, time and quality. Each one of these dimensions affects the other dimensions. If you shorten the programme time, then it will either cost more or the quality (of tests / commissioning) will be compromised. If you try to reduce the cost of it (cutting corners), again the quality will be.. Read More