Hybrid Car – More Fun with Less Gas

Looking for Ways to Reduce Electricity Usage (Possibly Solar Cells) - Page 3

register ::  Login Password  :: Lost Password?
Posted by Steve Spence on February 22, 2004, 4:39 pm
an 80 watt panel can't run a computer 24/7 in any part of the USA.
Most pc's draw more than 80 watts (itx and laptops excluded) and a max of 6
hours sun would only generate 480 watt hours (theoretical max), with a draw
of more than 2.4kWh's daily.

Steve Spence
Renewable energy and sustainable living
Donate $0 or more to Green Trust, and receive
a copy of Joshua Tickell's "From the Fryer to
the Fuel Tank", the premier documentary of
biodiesel and vegetable oil powered diesels.


Posted by Bob Adkins on February 23, 2004, 2:34 pm

You're right about that Steve.  What I was doing was giving the OP  an
approximate price on a "starting" system that would give him a feel for
solar, and could be added to later.

Upon further thought, his computers are quite power hungry. They would take
huge PV arrays and gnarly big batteries to do him any good. His money would
be better spent on LCD monitors and low wattage computers. Not much prospect
of payback either way he goes.


Remove "kins" from address to reply.

Posted by SayItAgain on February 3, 2004, 6:57 pm
 I'll second the Watts Up suggestion.  Also the suggestion that you look at
what's running all the time - e.g. anything that has a remote is on even if
it shows off.  Some are a couple of watts but it can run upwards of 20+
watts.  And that's 24/7.  LCD displays are nice but a KVM switch is the best
solution even if you do go with LCD.

As for the servers - it's a question of what they are doing as to whether 1,
2, or 4 are necessary.  Given your budget I don't see that you can upgrade
to low power PC's anytime soon.  You should look at the fans though.  Over
fanning a box will use some power but dirty fans (don't forget the fan on
the CPU!) will be worse all around.  Depending on where you can put them you
might be able to reduce the number and/or size of the fans if the PC's were
put in unheated space.  Minus 45 would keep them nice and cool.

Alternatively, if you can stand the noise, use the PC's as "space heaters".
My home office has a lowly 500 MHz PC with monitor and it provides enough
heat for the room with the register fully closed.

Finally it would help the suggestors if you posted your electricity use for
a couple of winter months and a couple of high summer months.  That would
give us a little better feel for your energy consumption.  If you were in
San Diego I'd say - give now but -45 isn't anywhere near that expen$ive



Posted by Mark & Mary Ann Weiss on February 3, 2004, 9:11 pm
 Hi folks,

Thank you for all the interesting comments/replies!
A couple of good leads on price and startup costs for PV systems. Thanks.

To answer some of the questions:

The PCs are constantly under load and cannot be turned off without
interrupting work. Two of them are almost new, custom-built PCs with 8 hard
drives in each tower, and GPUs (for accelerated 3D graphics), which I
recently learned, uses 75W of power by itself! One is serving web/internet
They are both based on top of the line Athlon CPUs, which to my chagrin,
produce a LOT of heat compared to the Pentiums they replaced, which is nice
in winter, because I never have to turn on the heat in this 1000sq ft studio
that contains them, but in summer, it's awful!
A large sum of money was spent on these and we plan to amortize them over 5
years, so no replacement possible before 2008.

Plasma Monitors are too expensive, as are LCDs, and they aren't available
with the resolution and size needed. At least I've never seen one spec'd
above 1600x1200 pixels. The other issue with them is they are inadequate for
serious graphics work. Move your head a little and the shade of color
changes, or looks metallic. They are not recommended for color-correction

The musical instrument samplers are left running on a secondary redundant
UPS (just in case the first one fails) because I have loaded into RAM over
900 samples. These have to be loaded at exactly the same address space/bank
# every bootup, or else it plays havoc with sequences I've written in
Cakewalk Sonar (for instance, having an oboe play instead of a spiccato
violin articulation). Because it's a pushbutton interface with archaic menu
system, it takes a long time to navigate and open a sample set, load the
particular programs and associated samples that you need (to conserve on
RAM) and then load the next. It's a lot like DOS, where you had to load
things one at a time using command line operations. So loading up 900+
sample sets and getting them into the bank addresses there were in when I
recorded the symphony originally can take over 2 hours. That's why I took
every step possible to prevent accidental loss of power to these two units.
They use 240W each.

The two largest computers each have a current draw of up to 8A when heaving
number-crunching is in progress. (At idle they use quite a bit less, and
also run quieter, emitting a loud 120hz hum when a CPU-intensive operation
is underway.) I've metered the computers using an inline AC ammeter and I
estimate that all the PCs together are using 20A.
The monitors have been replaced with Energy Star monitors that turn off.
Windows is configured to turn them off after 3 mins of idle time. Their
consumption is under a watt in the standby state.
The PCs each have 5 fans, no actually 6, counting the GPU 3D accelerator
cards. The Athlons need generous cooling or they literally go incandescent
in about 3 seconds (as I learned from watching a German PC test site
demonstrate the self-destruction without a heat sink) and the exhaust air
from the back of the towers feels about like a hair dryer on the 'warm'
setting. The other four fans are to cool the hard disk arrays (8 drives in
RAID arrays) and push/pull cool air through the chassis and motherboard. The
CPU has a 80mm 7000rpm fan rated at 16W. They are usually going at full
tilt, due to heavy number-crunching going on with both servers. It sounds
more like the transmitter room at a TV station than a PC with all those fans
going, but I guess that's the cost of high performance workstations/servers.

KVMs are not practical for me for several reasons:
Can't find one that works at resolutions above 1600x1200.
The PCs are too far apart at separate desks.
I worked with a KVM switch at a radio station I work at and frequently find
myself typing to the wrong computer.

I retired my main house sound system for anything less than full-frontal
concert-level listening, and now use a small mag-field amplifier and two
custom-built speakers. That knocked $6 off my monthly bill, by not having
an EIA rack full of pure class A amplifiers idling for several hours a week.

Regarding the heating system, it's hot water. Sorry I left out that detail.
A cartridge circulator at 3450rpm pushes the water through all the
convectors. (I've been seeking a heat reclaimer for the furnace stack, but
all leads to one on the web called "Magic Heat Reclaimer" have an error when
I try to order it.) In the meantime, I've insulated all the ring main hot
water pipes to maximize temps at the radiators.

$50 for an 800W panel and 2kw inverter sounds pretty attractive to me. A
source for these parts would be greatly appreciated.

About our fridge, I and the wife have been going over this for months. We're
almost settled on a certain Kitchen Aid model that's a side-by-side (her
demand) and fits in a 32" wide space that our old refrigerator and cabinets
are built around. But it's been hard to order this particular model locally,
and numerous things came up between last summer and the present, over which
we've been intending to purchase. It will likely happen in the spring, once
the snow has melted and a delivery truck can negotiate our mountaintop cow
path. (Delivering to a chateau in the Swiss Alps couldn't be any harder!) I
expect that will save us up to $2/mo.

Our chest freezer is in the basement, which is kept at 67F. But we don't
use it anymore, as we haven't bought a side of beef in quite a few years.
I'm still waiting to see if we saved anything significant by unplugging it
last November.

I like the idea of solar and wind power combined. Even though we are
densely-forested, we get good solar in the winter when the foliage is gone
and it's quite windy during season shifts here on the mountaintop. We're in
the northeast and we have been seeing temps of -10F here quite a lot this
winter. I think that any solar panel we use will have to be on a tracking
turntable, to follow the sun so it's always facing directly toward it. Such
a motor would be geared very low so that power consumed to rotate the array
should be minute. That's a project in itself, of course!

I can't put huge towers on the property (even though I can't see my
neighbors due to distance and trees) because of zoning restrictions. But I
thought about small turbines that catch wind from any direction of the
compass and turn even small generators--yes, multiple turbines--could be
mounted on the roof in various locations.

Last year, our electricity was $.11/KwH. This year it's higher, but I don't
have a bill handy at the moment to see the exact figure. One thing that
happened was the splitting of generation costs and delivery costs. We stayed
with the 'standard offer' generation provider. Oddly, the generation cost on
our bills equalled the total bill before the splitting of costs into two
categories happened. Two years ago, we were doing $0-$30/mo electric
bills, depending on load/season, and today, the $30 is the generation cost
and another $5 or so for delivery cost. They're talking about big increases
in rates this year to pay for the blackout of last year (upgrade costs for
prevention) so I'm encouraged to move some of my constant loads off the
grid, rather than go back to using a mechanical typewriter, which is what I
was doing 20 years ago, as I dreamed of composing music, creating complex
and realistic animations and authoring my own videos (now DVDs). I certainly
don't want to return to that era, but I don't see our electric bills staying
as low as $00/mo for long and so hence the need to gradually move the
continuous loads to solar/wind-powered sources.
I do envy some folks who live next to a small waterfall. I was driving down
one of the local roads recently and observed a water wheel turning on the
side of a barn. Something like that would be ideal, but alas, I have only a
tiny stream that passed the house and it dries up in summer.

Where can I get wind turbines? Are they integrated with a generator, or
purchased separately?

Looking out the window, I see another problem with solar panels... it's
snowing--again. Depending on where they are located, it could be difficult
to get to them to brush the snow off right away. So this system would need a
failsafe that could cut over to grid power when the battery charge falls
below a certain value.

I have to look at this as a scientific/fun project with a potential to save
some money down the road. I really don't mind significant up-front costs.
It's the monthly repeating drainage costs that hurt. Gradually, I'm chipping
away at all of these. Even refinancing our auto loan for a lower rate. Every
few dollars makes a difference!

Take care,

Mark & Mary Ann Weiss
Hear my Kurzweil Creations at: http://www.dv-clips.com/theater.htm
Business sites at:

Posted by Roger Gt on February 4, 2004, 1:25 am
wrote in message

pretty attractive to me. A


For starters.  That must be either used or a
misprint.  Best prices I see lately is #3.39 per
watt for a PV panel in 75 to 140 watt panel sizes.

You still need a charge controller, batteries, and
an inverter that will handle the full load
(derated to last.)

X-No-Archive: yes

This Thread
Bookmark this thread:
  • Subject
  • Author
  • Date
please rate this thread