TOP TIPS FOR COST EFFECTIVE
DATA CENTRE OPTIMISATION
MEASURE AND MONITOR
Stage 1 - Measure!
Use existing tools like your BMS or even the good old electricity bill to understand what your energy consumption is. The more detailed the better UPS, cooling system, IT load are the key ones. If that’s not possible then at a minimum understand the total kW & kWh of your site. Within the white space measure temperature and humidity. Make a simple grid of your room/rooms and take measurements. Ideally in hot and cold aisle at 1.5 m height. The more detailed the better but some kind of baseline is important to compare to once improvements are made.
Stage 2 - Monitor!
When making optimisation changes start small, implement, monitor and evaluate.
Top Tip #1: TURN IT UP
Increasing the set point of your cooling system by 0.5 C° or 1 C°. Monitor for 7 days and evaluate against your baseline.
Top Tip #2: SLOW DOWN
Decreasing the fan speeds of cooling units by 5%. Again, Monitor for 7 days and evaluate against your baseline.
Top Tip #3: PAPER OVER THE CRACKS
Use simple techniques with your eyes and a piece of paper. Look and find out where air is escaping from your raised floor and simply block the holes. Do the same for above, below and between your racks.
BLANKING, BLANKING, AND MORE BLANKING
Bypass air is money down the drain so stop it from happening. The same as floor tiles. Getting airtight racks will help make those little changes towards big savings.
Temperature increase
Consider increasing the set points of your DC cooling system only when you have optimised your floor and blanking.
Top Tip #1: JUST ***KING DO IT
Every ‘RU’ in a rack should be filled either with equipment or a blanking plate. Blanking panels are not expensive. Duct tape is even cheaper. Do whatever it takes. Don’t forget the very top, bottom and most important, sides. Especially on wider (>600 mm) racks.
Top Tip #2: BLOCK IT
Check if the top of your rack has vents. Block them off. Side cable management causes a lot of bypass air. Use brush strip or foam. The very bottom of a rack leaks a lot of air. Foam is ideal for this.
Top Tip #3: OVER SENSITIVE
Find the most thermally sensitive item of IT equipment and understand it’s thermal operating range. My experience says it will be much higher than you think. A server from Y2K can operate up to 35 C°. Use this as basis for the lowest cold air delivery temperature.
Top Tip #4: CONTAIN YOURSELF
In uncontained aisles aim for 24 C° cold air. Containment will help push this higher but 24 C° is achievable.
MANAGE YOUR RAISED FLOORS
Hot aisles should be that, HOT. Cold aisles…..you guessed it, although not to cold. 21 C° should be the absolute minimum goal. Aim higher if your able to, but remember! use small changes one at a time.
Top Tip #1: BLOWING HOT & COLD
Don’t use cold air grilles to “push” hot air from high density racks INTO COLD AISLES.
Top Tip #2: HUMAN ERROR
Ensure engineers do not move air grilles to make working on equipment more comfortable for them, AND THEN NOT REPLACE THEM.
Top Tip # 3: MIND THE GAP
….or gaps in your floor (tiles, edges, cable paths) cost money. Block them off. (HOW?) Getting the floor as close to air tight as possible (apart from grilles) will help in pushing up temperatures, reducing fan speeds and releasing savings.
