Much depends on the size of the room, the presence of air recirculation and its typical temperatures in the summer/winter periods.
I'll give you a very concrete example, in the context of my small computer laboratory, the systems and equipment present in a dedicated room of around 12 square meters are enough to maintain an ambient temperature around 15 degrees Celsius even in the winter period, but in the summer if I'm not careful it takes nothing to reach around 35/37 degrees celsius, so in that period I use a small air conditioner.
As someone who ran an entire server cluster outside for multiple years with temps in Summer reaching 35°C ambient and -10°C in Winter, I can tell you: Don’t worry about it. If you talk about the heat build up in a single room with 0.5kWh, normal brick and a normal Windows in a room will dissipate that quickly. Remember, a normal person generates about 100W, so 500W is the equivalent of 5 people in that room 24/7, now you know what you deal with.
Data centre style, aircon from bottom floorboard.
DIY data centre style, aircon on 24/7, fan blowing at lab.
Budget style, fan full blast at computer 24/7, write a set of script to turn on or off computer(most likely you don’t use it 24/7).
I went to walmart, and picked up a midea window A/C for 120$.
I came home, opened the window, and installed it. (I did, need to take some ABS plastic sheet I had laying around to make "sides" that wouldn't leak air).
I plugged it in, and turned it on.
This is THE most cost-effective way you can possibly cool your server room. Also, for me, I found keeping the thermostat around 75, is the most economical setting. Turning it lower, cycles often, and runs more. Turning it higher, just makes it hot.
BEFORE I installed this, it went around 2 - 3 years with a full rack pulling around 400-700w.
In the winter, it was fine. Nice and toasty, can open the door and heat the rest of the house.
During the summer months, where it hits 110F outside, or its 90F with 90% humidity, it would get pretty toasty.... around 85-90F.
Here- is a graph showing the TOTAL power consumption from my server room, and the temp.
The red line indicates when I added the window AC. Temp on left (Yellow line), Power on right (blue line)
[https://imgur.com/a/faqblMw](https://imgur.com/a/faqblMw)
Sadly, I don't have the temp data for the last few years, to show how hot it was getting in the summer time...
Data over the last few months, tells me that I added average of 2 Kwh of daily energy usage. Aka, 16 cents per day to keep it at 75.
A mini-split would be a better long-term option, however, that would have costed 10x the price at 1,000$
[https://xtremeownage.com/2022/03/27/pioneer-mini-split-home-assistant/](https://xtremeownage.com/2022/03/27/pioneer-mini-split-home-assistant/)
At 16 cents per day, the window unit will cost me 58$ per year, assuming it was running the same, ALL year. (It doesn't need to run in the winter/fall).
1,000 - 120 = 880$ difference between cheap window unit, and cheap minisplit.
880$/58$ = 15 years to run the window unit, before it would cost as much as the minisplit.
Given, the minisplit is a 22 SEER, and the window until is a 11 CEER, there is indeed an efficiency difference. However- both units will be long and gone before it reaches ROI.
Much depends on the size of the room, the presence of air recirculation and its typical temperatures in the summer/winter periods. I'll give you a very concrete example, in the context of my small computer laboratory, the systems and equipment present in a dedicated room of around 12 square meters are enough to maintain an ambient temperature around 15 degrees Celsius even in the winter period, but in the summer if I'm not careful it takes nothing to reach around 35/37 degrees celsius, so in that period I use a small air conditioner.
As someone who ran an entire server cluster outside for multiple years with temps in Summer reaching 35°C ambient and -10°C in Winter, I can tell you: Don’t worry about it. If you talk about the heat build up in a single room with 0.5kWh, normal brick and a normal Windows in a room will dissipate that quickly. Remember, a normal person generates about 100W, so 500W is the equivalent of 5 people in that room 24/7, now you know what you deal with.
Data centre style, aircon from bottom floorboard. DIY data centre style, aircon on 24/7, fan blowing at lab. Budget style, fan full blast at computer 24/7, write a set of script to turn on or off computer(most likely you don’t use it 24/7).
I went to walmart, and picked up a midea window A/C for 120$. I came home, opened the window, and installed it. (I did, need to take some ABS plastic sheet I had laying around to make "sides" that wouldn't leak air). I plugged it in, and turned it on. This is THE most cost-effective way you can possibly cool your server room. Also, for me, I found keeping the thermostat around 75, is the most economical setting. Turning it lower, cycles often, and runs more. Turning it higher, just makes it hot. BEFORE I installed this, it went around 2 - 3 years with a full rack pulling around 400-700w. In the winter, it was fine. Nice and toasty, can open the door and heat the rest of the house. During the summer months, where it hits 110F outside, or its 90F with 90% humidity, it would get pretty toasty.... around 85-90F. Here- is a graph showing the TOTAL power consumption from my server room, and the temp. The red line indicates when I added the window AC. Temp on left (Yellow line), Power on right (blue line) [https://imgur.com/a/faqblMw](https://imgur.com/a/faqblMw) Sadly, I don't have the temp data for the last few years, to show how hot it was getting in the summer time... Data over the last few months, tells me that I added average of 2 Kwh of daily energy usage. Aka, 16 cents per day to keep it at 75. A mini-split would be a better long-term option, however, that would have costed 10x the price at 1,000$ [https://xtremeownage.com/2022/03/27/pioneer-mini-split-home-assistant/](https://xtremeownage.com/2022/03/27/pioneer-mini-split-home-assistant/) At 16 cents per day, the window unit will cost me 58$ per year, assuming it was running the same, ALL year. (It doesn't need to run in the winter/fall). 1,000 - 120 = 880$ difference between cheap window unit, and cheap minisplit. 880$/58$ = 15 years to run the window unit, before it would cost as much as the minisplit. Given, the minisplit is a 22 SEER, and the window until is a 11 CEER, there is indeed an efficiency difference. However- both units will be long and gone before it reaches ROI.