[geeks] Ran the numbers - V240

[Lionel Peterson]

 Wow.

So last night I sat down and ran the numbers, and I can see why sun
V240 are available so cheaply... The cost to run them is quite high!

Here in Texas, using a state average of 9 cents/KWhr, the numbers look
like this:

24 hours/day x 365 days/yr equals 8,832 hr/yr

The fully-loaded V240 consumes 385 watts/hr, based on an in-line "watt-a-meter".

So to run this machine for a year the cost is:

385 watts/hr x 8,832 hr/yr equals 3,400,320 watts/yr, and when divided
by 1,000 watts/KW
give you an annual power appetite for the V240 as 3,400 KWhr/yr.

Multiply the 3,400 KWhr/yr times the cost per KWhr of $0.09/KWhr and
you are looking at $306/yr.

Divide that $306 by 12, and that means running the machine for a month
will add about $25.20 to my monthly power bill.

Wow.

For my 24x7 purposes, I was going to run a handful (5) of small VMs,
serving up small personal websites - I can almost justify the monthly
cost (it would work out to $5/month per site), but then something
caught my fancy, a nifty rack that is no bigger than a half gallon
carton of milk that holds 6x Raspberry PI boards for about $30, and
that got me thinking...

I googled "power consumption raspberry pi 3" (no quotes) and found
that at 400% CPU load (all 4x cores running at 100%, worst-case), the
Pi 3 consumes about 750 ma/hr or 3.7 watts/hr.

Running the same calculations again, a single RPi 3 consumes about 34
KWhr/yr, and at a cost of $0.09/KWhr, a single RPi 3 is about
$3.94/yr, or about $0.75/month. And thinking about my application, a
single RPi 3 could likely handle the any worst-case load any of my
sites would ever see, so the numbers come down to this:

To run the V240 on older Solaris without access to security patches
(but scoring booku "Geek Points for running a public Solaris web
server at home) would cost me $5/month. Hardware costs are zero, I
have the server already.

To run 5x Raspberry Pi 3 running Linux on them, with full access to
security patches (and scoring slightly fewer "Geek Points" for having
a Raspberry Pi datacenter on my desktop) would cost about $3.75/month.
Hardware costs are steeper:

5x Raspberry Pi 3B at $35/each = $175
5x 32 Gig microSD cards at $10/each = $50
1x multi-port cellphone charger (6x USB ports, 60 Watt capacity) = $20
5x micro USB to USB cables (power for RPis) = $10
5x 1 ft Cat 5 cables = $10
1x 8 port Ethernet switch = $15
6x RPi rack from etsy = $30

Total Hardware cost: $310

Total first-year cost is nearly identical ($0 + $306 = $306/yr for
V240, $310 + (5x $4/yr for 5 RPi) = $330/yr for the desktop RPi
datacenter, but for year 2 of operation the cost is another $306 for
the V240 vs $20 for the RPi datacenter...

Looks like I may be going out shopping for some Raspberry Pis!

Thought others might find the math/numbers interesting.

Lionel
-- 
Lionel Peterson
lionel4287 at gmail.com