[geeks] Ran the numbers - V240

[Jonathan Patschke]

On Thu, 9 Nov 2017, Lionel Peterson wrote:

> 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".

Double that for the 9 months out of the year where air conditioning is a
reasonable requirement for comfort in Texas, unless your HVAC is
particularly efficient.

When I lived in a much smaller house out in the country, there were a
couple of machines (AlphaServer 2100s) that were great for heating the
place, but not reasonable to run during the warm months.  A few years
later, virtualizing all my SGI, Sun, and IBM hardware into FreeBSD
jails cut my home electric bill by over $400/month.

I've got a V210 open on my desk right now, and its power supply was
designed by the same company that did the one in your V240.  It claims a
maximum input draw (not including the initial inrush) of 500VA, and a
maximum DC output of 320W.  Yours claims 650VA in and 400W out, making it
somehow worse, despite being physically larger.

No amount of tinkering is going to bring that down to RasPi MIPS-per-watt,
but there might be some low-hanging fruit in fitting a modern "80+" 1U PSU
in there.  The rails seem to be about the same as what an PC uses, but the
connector would need figuring out.

There's probably generally a lot of economization to be done in replacing
linear PSUs with switchers, old switchers with more efficient switchers,
and spinning rust for solid-state storage.  It'd be nice to be able to run
older kit without raising the temperature so much, and there are some
interesting things going on with the Open Compute Project that might
retrofit well.

-- 
Jonathan Patschke
Austin, TX
USA