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Sorry Pete and Tim, but you are both wrong. Each of your posts
were riddled with errors and misconceptions (possibly assumptions of your
own?), but you plugged them in to your analyses and came out with an answer that
you based your conclusions on. I have to admit, I'm surprised. Such resistance
to new ideas, when you have both embraced my father's work and spoken out
harshly against the resistance he faced?
I don't expect you to simply "take my word for it". Therefore, I
have taken the liberty of forwarding on the two posts to an expert in
alternative energy that I happen to know and, rest assured, I will post the
results of her investigations.
Judith
Sent: Saturday, November 08, 2003 8:30
AM
Subject: [ROSEN] FW: Tholar Energy
Mythth
Forwarded on
behalf of Pete Giansante.
(The server had
rejected it:
The enclosed message, found in the ROSEN
mailbox and shown under the spool ID
6473672 in the system log, has been identified as a possible delivery
error
notice for the following reason: "Sender:", "From:" or "Reply-To:"
field
pointing to the list has been found in mail body.
I think it was
because there was a hyperlinked "mailto" in one of the
included headers.)
Tim
-----Original Message-----
From:
Pete Giansante [mailto:***
Sent: Saturday, November
08, 2003 6:25 AM
To: ***
Subject:
Tholar Energy Mythth
(...Yeth, thatth the plural of
"myth" with a lithp.)
Judith is correct in her preference for using
renewable resources like solar energy wherever they are appropriate. Tim is
correct in his assertion that intensive, reliable, on-demand power generation
is not one of those applications.
NOTE:
"Intensive"
means that the backup power generation technology is capable of completely
replacing centralized grid-supplied power (by which I mean your electrical
utility company) for any period of time that might be required to provide an
uninterrupted electrical energy supply. [ energy = power x time,
usually expressed in kilowatt-hours (kWh)]
"Reliable" means that the backup power supply
can operate as long as needed. If you want a number, call it "a minimum of
95% operation/a maximum of 5% downtime for maintenance".
"On-demand" means that the backup power
supply is available whenever you need it.
The economics of
installing engine-driven generators must indeed be balanced by the ROI such an
investment would make. In addition to the capital cost of the power
generating, distribution, & switching equipment, and the facilities to
house it, there's the expense of storing and recycling fuel (usually Diesel
No. 2) -- with all its associated regulatory hassles. Add to that the
personnel cost of maintenance & operations, and you have to have a very
compelling reason to load that kind of cost into the goods/services you offer
your customers. In fact, if your competitors decide against going that route
and the market prefers the resulting lower prices of their goods/services, you
won't have any customers. Gas turbine
technology has improved, but it's more costly in capital & maintenance.
Regardless, if you want reliable backup and your market provides the economics
to support it, you're going to be going with some form of combustion
engine-driven generating plant.
Solar energy works pretty well in a
thermal application -- that is, for heating water and living space. Electrical
power generation from solar energy is an entirely different matter. It can be used to generate
electrical energy via photovoltaic conversion, as long as one is willing to
accept conversion losses on the order of 90%. Even if such losses are
acceptable, you still can only collect and store enough energy to operate
things like radios, stereos, and high-efficiency lighting (e.g., fluorescent
or metal halide vapor lamps; forget about incandescent -- thermal losses are
too high). But if you want to do a lot of intensive usage (e.g., air
conditioning, electrical appliances, power tools), you're not going to be able
to run that kind of stuff using photovoltaic conversion without prohibitive
equipment & maintenance costs. The cost in lead-acid storage batteries
alone would eat you alive -- assuming you even wanted to have that much
hazardous stuff lying around.
I sympathize with the hopes of solar
energy enthusiasts, but they would perhaps be better served by a somewhat more
realistic appraisal of the ability of solar-powered infrastructure. As a
source of large-scale, intensive, reliable power generation,
solar/photovoltaic conversion is more mythology than technology.
Consider the physical constraints. The maximum terrestrial incident
power flux of solar radiation is ~1 kW per square meter when the sun is
directly overhead and is unobstructed. The sun's output imposes that physical
limitation, given the radius of Earth's orbit, and there isn't much we can (or
should) do about it.
Perhaps some concrete examples will help to
illustrate how that limitation affects our ability to use the sun as a
practical source of electrical energy. To convert the incident solar power to
energy, multiply by the amount of time that the 1 kWh/m^2 condition is in
effect. First, you must account for the seasons. The maximum solar collection
time that you can squeeze out is 12 hours per day, twice per year... if your latitude is somewhere between the
two tropics. The rest of the year you have considerably less daylight, and
more atmospheric interference as the sun's path drops to the horizon
seasonally, so on average you have maybe 10 hours of usable sunlight per day,
under ideal conditions. If your location is between one of the tropics and the
nearest pole, it goes downhill from there.
Now you must also account
for the daily rotation of the Earth. Even under the best of conditions
(desert, during the summer, with no cloud cover), you have that condition for
maybe one hour before plus one hour after the sun is at zenith. Of course, the
sun isn't directly overhead for the other 22 hours in the day, but let's say
that you can devise some complicated tracking mechanism to keep the
perpendicular axis of your solar collector(s) always pointed directly at the
sun.
However, the average incident power won't be the full 1 kW/m^2
for the entire 10 hours. Call it 0.70 -- again being generous. That gives you
~0.7 kW/m^2 x 10 hr/day = 0.7 kW-hours/m^2/day of incident solar energy.
Assume that you fill the entire 1-meter area with photovoltaic cells and
capture all the incident energy. With a conversion efficiency of ~10% (that's
typical of current technology), here's your maximum electrical generating
capacity, under ideal conditions:
0.7 kW/m^2 x 10 hr/day x 10% = 0.07
kW-hours/m^2/day Now, since we've already
accounted for the seasons in our average daily capacity, we can annualize that
capacity:
0.07 kW-hours/m^2/day x 365 days/year = 25.55
kWh/m^2/year
That's under ideal conditions... meaning an arid climate
with zero cloud cover. For the average location in the U.S., cut that number
in half... so that's ~13
kWh/m^2/year
Now, compare that capacity to the
energy-intensive sources that we typically find in fossil-powered electrical
generating technology. That's how Southern California Edison generates most of
its power... by burning fuel oil or coal, so for comparison, the same capacity
can be converted to the equivalent amount of fuel oil or coal:
Fuel Oil:
13 kWh/year x 3,414 BTU/kWh = 44,382 BTU/year
44,382
BTU/year ÷ 139,000 BTU/gal. = 0.32
gal/year
Anthracite Coal:
44,382 BTU/year ÷ 15,000 BTU/lb. = 2.96
lb./year My average annual usage over the
last 36-month period is 20,385 kWh. Allowing for peak usage months, and based
on my existing 0.25-acre lot size, I could replace
the energy I'm currently getting from the grid if I were to cover 98% of my
property with photovoltaic cells... if I had ideal conditions,
and the money to spend on such things, and the
desire to live amidst that sort of ugly junk, and the
inclination to spend my time or my money servicing/maintaining such a
preposterous facility. I don't. Most people don't.
More to the point,
neither do the most vocally active "public figures" who advocate the mythology
of "soft energy" technology, and mislead others to believe that such
technologies are feasible.
I find the idea of energy self-sufficiency
attractive as a means of sustaining oneself when living in a remote location,
but even then, I would require a small generating plant if I wanted to
maintain the quality of life that I currently enjoy. The maximum conversion
efficiency attainable with current non-nuclear technology is approximately
50%, provided by high-speed gas-fired turbines. I suppose that when they can
be made reliable enough and can be mass-produced cheaply enough, it would be
feasible for individuals to own them.
Nevertheless, such a
decentralized system would sacrifice the economies provided by large-scale,
centralized power generation and distribution. As long as we rely on
combustion-based technologies, we might as well minimize the combustion
by-products via economies of scale. I should think that would be an article of
faith among anyone who is concerned with global warming (I'm not).
Of
course, the longer-term solution is to drop our reliance on combustion-based
technologies altogether. We have the capability to do that safely right now,
but (sigh) I'm not inclined to pursue such a controversial subject in this
forum... and besides, the content of this post has probably wandered too far
off-topic for this list as it is...
PVG
Tim Gwinn wrote:
-----Original Message-----
From: ROSEN Forum On Behalf Of Judith
Rosen
Sent: Friday, November 07, 2003 10:35 PM
To: ***
Subject: Re: FW: L-Soft service unavailable on Saturday, November 8,
2003
Why can't they invest in a couple generators? Better yet, why not go
solar??? That's what I'm doing... I've got a handicapped child who has
medical equipment that needs electricity. But even if I didn't; energy
dependence and vulnerability to grid disturbance is the single biggest
immediate threat to the welfare of this country, the way I look
at it. There
are plenty of reasons, from all areas, ranging from health to
environment to
finances to national security to global stability, but in this case, it's
about commerce. Purely from a business point of view, how much money isn't
"made" when lack of electricity forces shutdowns like this one? Lost
economic development because of something so preventable is a damn shame.
Well, I think exactly because it is about commerce that they are probably
not investing in generator backup. :)
Statistically, an outage of more than several hours is extremely low, and
the capital cost and ongoing costs for generators would have a very poor ROI
(return on investment). I'd imagine they have their systems on battery
backups, which typically will hold systems up for 2-8 hours depending on
what they've chosen. So, to have invest in generators would serve to
probably only change their uptime from 99.99% to 99.999% or something like
that. They probably have more downtime due to hardware/software failures
than power issues. Also, since mailing lists are not "mission-critical"
services (like a hospital or 911 system, or in business, like a
stock-trading biz), the rare outage of a day or less are not enough to make
customers go elsewhere.
As for solar, at this time it is simply not very feasible. The conversion
efficiency is very low, so to run real-time off of panels requires alot of
square footage. Plus, because solar supply is so intermittent, based on
time-of-day and weather, real-time usage of solar is impractical and instead
it requires a huge investment in some kind of power storage (batteries) if
you intend to have it "on-demand" or for mission-critical applications for
any length of time beyond what a normal battery-backup system would handle.
A warehouse full of storage batteries and power inverters would be a big
cost, and in a business environment would probably be classified as
hazardous materials by OSHA & EPA.
Maybe thin-film photovoltaics and fuel cells will help some this situation
some. Speaking of fuel cells, I am skeptical about hydrogen as a ubiquitous
power storage medium - it strikes me as much too volatile and difficult to
safely store in a density that wouldn't require a huge vessel. Maybe I'm
just a cynic, but I think that the "hydrogen economy" is way oversold as
being viable anytime soon.
These methodologies have one thing in common: they are all entirely
mechanistic.In the long run, I wonder if it would probably be better to have
biological partners to generate our power needs or act as power storage
resources: growing mats of electricity-producing moss on our house roofs,
etc. Maybe we can make use of the way in which different observers "see"
items differently, by storing energy in forms that are, to us, non-volatile,
but to a colony of some certain microbe are an energetic feast. Certainly
these are things that are not near-term, but I find the idea of living in
such a world fascinating.
Judith
PS: On an unrelated issue: RoadRunner has lost me as a customer as of
Monday. They have a nasty policy of blocking whole internet
service domains
based on suspected spamming by anyone in the domain. If anyone
has tried to
send me email and had it bounce with a security notice attached, that's
RoadRunner. They do not even notify me that this is happening.
I'm moving to
Earthlink as my ISP. The new email address is
*** and
it's up and running already. Tim, you can unsubscribe this RoadRunner
address and substitute the Earthlink one, by Sunday. Thanks, folks, and
sorry for the inconvenience!
I'll change the email. Not that its any consolation, but Roadrunner isn't
the only culprit. AOL is notorious for blocking domains erratically
supposedly because of spam. Comcast, too. List admins on Lsoft are very
frustrated with this, since companies like AOL or Comcast willl not listen
to them, and sometimes not even to Lsoft.
Earthlink has been good for me over the past several years, and I still keep
an account going with them.
----- Original Message -----
From: "Tim Gwinn" <***>
To: <***>
Sent: Friday, November 07, 2003 7:18 PM
Subject: [ROSEN] FW: L-Soft service unavailable on Saturday, November 8,
2003
To all listmembers:
This notice arrived on the list administrators support forum.
Tim
-----Original Message-----
From: L-Soft EASE Home Support Forum
[mailto:***]On Behalf Of Nelson Chen
Sent: Friday, November 07, 2003 3:50 PM
To: ***
Subject: L-Soft service unavailable on Saturday, November 8, 2003
On Saturday, November 8, 2003, the electricity will be shut off
from 7:00
a.m. - 5:00 p.m
by our building management in conjunction with Baltimore Gas & Electric
(BGE) for
emergency maintenance.
In light of this development, email traffic through our servers will be
temporarily
unavailable. We will be monitoring this situation closely and
will do our
best to
minimize any disruption to normal mail traffic.
We apologize for the short notification and for any inconvenience.
Regards,
--
Nelson Chen
L-Soft international, Inc
http://www.lsoft.com/
Support is available 9:00-18:00 ET, Monday-Friday
except on the following holidays:
http://www.lsoft.com/products/default.asp?item=holidays
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