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Efficient Computing & Wireless Internet
©2002 John Bertrand
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COMM. POWER A year ago, when we finally settled into our still
incomplete solar powered house, we set up our trusty three-year-old
computer. Then, having no landlines (electricity or telephone) we
installed a wireless broadband Internet connection. So we were sitting
pretty, right? Wrong.

In fifteen years of home computer use, we have never just left the
computer on all day. But times and uses have changed. Our computer has
become more and more of an appliance rather than a specialty tool. In
our new home, it became apparent that we needed it available constantly
for Internet research and e-mail. Yet leaving the system on, even in
sleep mode, used too much energy. Our fairly typical desktop system
draws 180 to 190 watts.

Flipping it off and on was too much of a hassle because of the almost 2
minute boot up each time we needed to check something. Besides, even
turning it on and off as needed was a serious drain on our 1.2 KW PV
system. Expanding our PV array (sixteen, 77 watt modules) was not an
option because the present rack and wiring are maxxed out, not to
mention the hassle of having to submit a new electrical permit
application, complete with engineering stamp.

The Search
So I began researching notebook computers. Without a doubt, they would
provide a much better energy use scenario. I wanted the lowest possible
energy use in a quality unit.

I have always purchased desktop systems from smaller companies that
offer good quality parts for the money. I could always make changes
later if necessary. But notebooks are a different animal, since they are
more or less a closed package. So it is very important that it has all
the functions you will need.

For many people, the notebook can replace the desktop unit. So a 14 or
15 inch (36 or 38 cm) screen, 5 to 7 pound (2Ð3 kg) ?desktop
replacement? machine will work. For others, a really lightweight 3 to 4
pound (1.4Ð1.8 kg) unit with a 10 to 12 inch (25Ð30 cm) screen is fine,
since the desktop unit is not being displaced, but supplemented and
networked. The former will certainly save watts over a desktop unit, but
with its built-in drives and large screen, will use considerably more
energy than the latter.

For us, keeping the desktop unit for graphics-intensive tasks seemed
desirable, since the screen is larger, and CRT monitors generally handle
graphics better. So I researched what was available in the smallest of
the Windows-based notebooks.

Our personal parameters included finding a highly rated, quality product
from a well-known company (such as Dell, IBM, Gateway, Micron, Sony),
long battery life, no built-in drives other than the hard drive (but
with an attachable CD/DVD drive for loading programs, etc.), at least
256 MB RAM and a 20 GB hard drive, a touchpad pointing device, and a
high quality graphics card that will not drop frames when playing a DVD
movie.

I began looking more than six months ago. Because of their customer
satisfaction record, I was somewhat predisposed to look most seriously
at the Dell offerings, in particular the Latitude L-400. But it was weak
on graphics and, having been on the market quite awhile, was not tops in
energy efficiency. We came close to trying a Sony unit available from
Costco for less than US$1,000, but it only had a 10.4 inch (26.4 cm)
screen, older chip sets, and mediocre graphics. That finally kept it out
of the running.

A Small Gem
In November 2001, Dell introduced a new model, the Latitude C-400. It
was much like the earlier L-400, but had updated processors (866 MHz or
1.2 GHz, running on half a watt), a new generation of energy-saving
Intel support chips (830M), graphics adequate for DVD movies, both a
touchpad and a pointing stick, and some other goodies I found desirable.

I watched the prices, including the Dell ?refurbished? units. In
January, after the Christmas rush was over, I kept close track and
finally bit on a good offer. (Remember, if you buy on the phone rather
than off the Net, you may be able to negotiate for even better than the
current sale prices, but beware of the frustrating sales-speak even from
reputable firms.)

This particular model best met our needs. The US$2,300 price is in the
midranges, with basic economy models available around US$1,000, and
corporate road-warrior models well above US$3,000. (Note: laptop prices
continue to fall, so you may be able to do even better by the time you
read this.)

In terms of energy usage, though, this model has to be near the lower
limit. We measured usage with a Watts up? meter. The meter isn?t
extremely accurate when measuring loads drawing less than 20 watts, but
it?s close enough for general use. In any case, the C-400 uses just 15
to 18 watts when in regular use.

This figure, when compared to the desktop system, is cause enough for
joy. But when we close the case, putting the system in standby (it goes
to hibernation in 15 minutes, or whatever you want to set), the usage is
too low to measure with this meter.


The radio system's receiving dish. The wireless Interent system only
draws 1 to 2 watts total.

 


The D-Link router and the radio transceiver allow completely wireless
Internet use.
Wireless Internet

When it comes to broadband Internet service, there are three major
routes and one minor route. Leading the charge these days is cable modem
service from the cable TV companies. This is followed closely by DSL
(digital subscriber line) service from the telephone companies.
Satellite service from the two satellite TV companies has made inroads
mainly where the other two services are not available.

Finally, in a few areas, ISPs have established fixed wireless service,
which uses a line-of-sight radio link between their operation and
subscribers. The radio signal is in the same frequency range as a
microwave oven, and can be fairly characterized as a ?microwave link.?
It conforms to the IEEE 802.11b standard used for wireless networking
within the home or office, and is theoretically capable of 11 MB per
second information transfer. A radio transceiver and small antenna are
required.

 

We had a choice of going to Starband satellite service or Interlink
Hawaii (local ISP) fixed wireless service. Starband was just becoming
available with no track record, high upfront costs of more than US$1,500
(installation is less expensive in the continental U.S.) and a monthly
cost of US$70. Interlink?s fixed wireless service had been around for
several years, had an installation package of US$500, and cost US$50 a
month. Needless to say we went with the latter, which uses a Breezenet
Pro.11 radio.

Overall, we have been very satisfied with the service. When our radio
was failing after less than a year (it is leased and was used), they
were slow to replace it. But otherwise, we have had mostly speedy
surfing, with very little downtime. And being a local company, they are
usually easy to work with. Power draw of the wireless system is 1 to 2
watts.

Over a typical day of turning the system on first thing in the morning,
using it for about 5 hours off and on, with it in standby or hibernation
the rest of the time (about 7 to 8 hours), the total watt-hours used is
84. That?s equivalent to about 25 minutes use of the desktop system! If
it is on standby, the C-400 comes back to full use in a few seconds.