If I could power even one computer by storage batteries and a solid state
sine wave inverter, charged by solar cells during the day, with enough
reserve to run the whole night throught til sun up, I would consider that
a
great start. Because of budget limits ($300-500) this will be a DIY
project.
I'm not sure this is going to be easy. How many monitors are you running?
You can invest in a box that will allow you to use one monitor with all 4
servers if you haven't done that.
I am hesitant to spend a lot of time on alternative energy if the technology
hasn't progressed a lot since I last looked into it (the late 1980s) and the
cost hasn't come down substantially.
As for the monitors, I have 2 21" monitors that go on standby after 3
minutes of non-use. One 17" monitor that is turned on once a week to change
a server configuration, then it's powered off the rest of the time.
The biggest hogs seem to be the server boxes, using about 6 times as much
energy as one 21" monitor in operating mode. The servers are drawing between
6 and 8 amperes, depending on whether they are idle or running CPU-intensive
CAD rendering (the power supplies start to hum audibly when CPU load
increases, interestingly enough!)
Any figures on how much a 42-yr-old fridge uses as compared to a modern
Energy Star rated fridge? That's another area where I suspect we are
wasting.
I've checked everything else.. the water pump is not cycling unnecessarily,
the furnace is running well, circulator not running excessively.
The big drain seems to be the Athlon servers (8 physical hard drives in
each, too) and to my advantage in the winter, they heat the 1000' square
foot studio in which they reside adequately that I don't need to use the
main heating system until it gets down to the single digit temps. But in
summer, this is a liability. I also did some tests timing the spin rate of
the demand meter and found that the two big monitors barely affect the draw
of power, but when the servers are powered up, the spin rate really gets up
there. Everything's on a 3kVA UPS, so it's easy to pull the plug and watch
the meter come to a near-standstill. That was an eye-opener. Gone are the
days of PCs that used less than 200W. :-)
A few years back, I heard about "thin film" solar cells and they were in
the
experimental stages of development, but claims of efficiency completely
blew
convention cells out of the water. Are these new cells on the market
today
and are they as efficient as the early Popular Science articles
suggested?
The efficiency is HALF of current solar cells. The advantage is that they
are cheap. I just read an article about NASA planning on using them for
satellites. I don't think they are commercially available yet.
Okay, so it's price, not performance that they offer... but depending on HOW
much cheaper they are, it might be possible to use 3-4 times as much cell
area for the same price, gaining a near 2:1 price/performance improvement.
But I don't see anything less than multithousands in cost that provides any
useful amounts of output yet.
I figure I have a constant 20A draw on that UPS (all computers together) and
if the primary is 48VDC, then I'm looking at just about 60A of load on the
batteries (figuring inverter losses of at least 20%), so to run overnight, I
need at least 600Ah of battery capacity. To match the load, I would figure I
need at least 60A of output from my solar panels at 48VDC to maintain the
charge. That's a LOT of solar cells. Add to that the fact that we're in a
heavily wooded area, with decent sun in winter, but very little in summer as
a result, so we're gonna see maybe 20% of their output in summer.
I'm looking for a variety of alternative energy source ideas, even wind
power to charge batteries.
Perhaps it makes more sense to have one big 3kVA inverter and three times
the battery capacity and more cells charging by day and wind-driven
generators charging by night?
This may work but batteries need to be replaced every few years. Don't
make the mistake of not figuring that into the cost.
Yes, though fortunately, lead acid batteries for RVs and tractors are
becoming less expensive, yet more powerful. I figure we'd see 4-5 years good
use before replacement. So a couple hundred in replacement batteries every
five years is not bad. That's 1-2 months regular electric bills.
You're best bet may be a fuel cell. I think they ARE commercially
available but you'll need natural gas to run it.
An interesting concept, but I don't want natural gas or propane canisters
anywhere near my house. Though not likely, the catastrophic results of a
mishap with gas are too great to risk.
Is anyone on this discussion group doing serious alternative electric
energy
generation?
Nah, I just pay the big bills.
We have been too, but we recently had a major increase in property taxes,
plus our electric bill nearly doubled since 2001 (despite our taking
numerous energy-reducing measures like shutting down our freezer, not using
the big sound system as a background/monitor system, getting rid of our 12
year old 21" NEC monitors and replacing with Energy Star monitors that can
power down after an idle period, banning the use of electric space heaters,
etc. We've cut our usage from 50kWH to 28kWH per month by doing this. But
the bills have done the exact opposite, increasing from a range of
$72-$140/mo to a constant $200/mo with the occasional $160 bill.
Income is flat, while other costs are rising rapidly (not to mention fuels
like No2 oil and gasolene!) So it's imperitave that we find cheaper energy
sources, lest we go back to using candles and woodstoves again. :-)
--
Take care,
Mark & Mary Ann Weiss
VIDEO PRODUCTION . FILM SCANNING . AUDIO RESTORATION
Hear my Kurzweil Creations at:
http://www.dv-clips.com/theater.htm
Business sites at:
www.dv-clips.com
www.mwcomms.com
www.adventuresinanimemusic.com
-