Are you a fan of fans? Centrifugal (I prefer to call Centripetal but that’s a tale for another day), Axial, Cross flow, whichever you like, fans can prove to be a challenging topic. A recent series in the Ashrae Journal discusses industrial fans, but what got me thinking about the topic of fans was a much smaller situation. PC computer fans.
Your standard 120 mm PC fan is a fairly homogenous product, but there also exist other fans in the same frame size with considerably higher energy use, cfm, and static pressure capability. These fans can be used to cool equipment, like say a bitcoin miner or a 4U server, sometimes coupled with a direct chip to water to air setup (something like this).
So which use of fans is best? 1 really impressive fan (like this) or 2 run of the mill fans stacked or 2 run of the mill fans next to each other (like these). The single fan consumes 30 watts, while the 2 fans consume 4 watts each. The 30 watt fan moves 240 cfm, while the cheapo fan moves 70 cfm. How much air do you need, and how much static pressure do you need? These fans get slapped in an application but they won’t move that same air volume with any resistance. That’s where the fan curves come into play.
For those of you that don’t know I started in the industry as a facilities technician, then within three months became a site lead mechanical engineer. One thing that always perplexed me was the persistence of the 15-ton (or any nominal sized refrigeration component) compressor. Even today, working as a regional engineer over 3000 miles of data center footprint, I still deal with this from people who should know better.
I just received the check from our major project at the CH2 data center in downtown Chicago. A $544,000 rebate for validating our energy savings is a pretty impressive feat. The projects included VFDs on DX Cracs, modifying the BMS and economizer, installing hot aisle containment, installing lighting occupancy sensors, and upgrading the cooling towers with new fans and new evaporative media. They tell me this is the biggest check they have ever issued and we are doing a big presentation ceremony in a few days to celebrate this projects successes. Big congratulations to the team I worked with that made this all a reality, Dan Fargano, Travis Nelson, and Jason Brick.
This is geared toward the colocation side of the data center world.
Working in such an engineering based and high tech field it is easy to forget what really allows us to bring home the bacon, our customers. Colocation data centers would not exist without the customers to fill them up. While you may have good customers and difficult ones, we should all approach our business with them in mind. Now I am not going to get into a philosophical conversation whether “the customer is always right” or not. This is not the time or place. I will focus on small changes that will help out the customers and in turn the data center staff.
Happy Earth Day! I just wanted to take some time to acknowledge this occasion and what I think it means to data center operators.
Earth Day started around 1970 and when it gained traction, the idea was to educate and inform while celebrating our planet. Well in that vein, I did some reading today on energy efficiency and conservation. Where else, besides in heavy industry, do we have the opportunities to save millions of kWh a year? Lots of different estimates of energy consumption exist, but roughly 1.5-2% of all energy is spent in data centers in the United States (good luck finding a solid source for that number). And as IT becomes a bigger sector of the economy, so too has the consumption of data centers increased. These old centers give us so many opportunities.
This week I had the pleasure of presenting at the Uptime Institutes Group 3 and 5 network Conferance with my colleague John Gray. First, let me thank the Uptime Institute for the opportunity and also the terrific audience. We received terrific feedback and engaged in some really great discussions. I would also like to thank the other presenters for their fantastic presentations, especially the team from Thompson Reuters who presented on two fantastic topics and the Fidelity team for hosting and providing great input to the group. What a week!
I just read an interesting article providing a nice contrarian perspective on airline travel domestic and abroad. It compares the cost of a life saved relative to money spent in other areas. Keep in mind, I’m writing this at the airport so I am painfully considering the implications of the points I am making. While this may seem ludicrous at first, the idea of making something less safe, I realized that this might help me make an interesting point effectively, one that I struggle to articulate. The article points out how more effective spending on vaccines, safety belts in cars, and other areas of our lives relate to the money spent on aviation safety. Because of very effective FAA regulations, poor countries spend a lot of money on aviation safety while school children are unvaccinated and traffic deaths occur at significantly higher rates.
So what point, relating to data centers, could I be getting at? Are we spending money in the most effective manner to realize high availability. Much like the net loss of life in poor countries would be lower if they allocated resources where they have the most impact, so too we can improve our loss of compute by investing where impacts are highest.
For all those looking for some easy peasy NPV calculations I put together a spreadsheet. Please note, I am always open to improvement so if you see something that can make it better please let me know.
Just fill in the yellow boxes (I have locked down discount rate at 10% and inflation at 3%, if you know enough to want to play with that let me know and I will give you the unlock password). Select 10 or 15 year project life, and the spreadsheet will auto manipulate. This is focused around energy savings projects but you can use anything with a cash flow that will accelerate with inflation.