Environmentally Conscious Designs

[Soundlabz]

In my research on alternate energy sources and self sustaining
buildings and homes I came across a website that may be of interest to
the group Treehugger.com. Of particular interest to me are the AC
versus DC threads that are debating the efficiency of AC-DC conversion
and the topics of grey water collection and storage for future reuse
for sanitary purposes. My suggestion for a future meeting is to
brainstorm some ideas for efficient designs and projects utilizing
everyday items. An example would be a design using solar panel-
rechargeable battery- direct to desktop computer by removing the
existing 120vac power supply and rewire for direct dc power.) If
anyone is interested in this topic or a future project let me know.

Mike

[Nick Johnson]

Cool!

I had a similar idea: laptops have an AC adaptor, but the plug in the
back of the laptop is 20VDC. I've always wanted to rig-up a
stationary bike generator to power my laptop, and skip the DC-AC-DC
inversion steps.

Also, reminds me of a solar water heater made out of an old fridge:
http://www.cheaphack.net/2008/02/how-to-make-solar-water-heater-using.html

It sounds like a good idea for a future meeting!

BTW - I'll write a recap of last night's meeting. Ken: do you have
photos from the melt that I can include?

Nick

--
Nick Johnson

[J.D. Abolins]

For inspiration, take a look at the Greener Gadet competition site:
http://www.core77.com/greenergadgets/

Does anyone have a device such as Watts Up or Kill-a-Watt? We've did
some experiments at work using such devices. One of the interesting
things was the impact of Web site colour schemes upon power
consumption by CRT monitors. Google-sytle (dark text on white)
consumed more power than a mostly dark site. (Black with medium light
or grayish text was good. Hacker cool but hard to read.)

Thought about "vampire devices" -- devices that suck current
continuously even when the primary function of the device is not in
use: the problems are compounded by the push to have separate wall-
warts for each device. (Good for the vendor parts revenues, bad for
the rest of us.) A single DC source with multiple adjustable &
switchable output connectors might be an interesting thing for
tinkering.

History note about "vampire devices": I first heard the term used in
US reporting in 2000 - early 2001. There was some talk about the Bush
Administration doing something about these devices. That got
overshadowed by the events of September 2001 onwards. Nobody seemed to
even remember the pre-9/11 references to "vampire devices".

Jonathan

[Soundlabz]

I'm happy to see that other members have equal interest. If I'm not
mistaken isn't one characteristic of DC power the ability for the
power to be stored for future use? Aren't these "vampire devices"
actually cheap leaky transformers and rectifiers? Are most of these
devices converting high voltage ac to low voltage dc? I've read that
the average leakage can be anywhere between 1-10 watts per device. I
count over 40 of these devices in my home alone. Examples are my
computers, printers, TV's, hard drives never mind my studio equipment.
A small inefficient PV could easily handle this wasted power. But by
integrating a dc power source as Jonathan stated with storage capacity
and multiple taps (dc-dc converters) has the potential to power all
these devices efficiently. Current technology for electronic devices
has removed internal power supplies so that the products are generally
universal and running on low voltage ac or dc. Maybe we can try a
simple converter with an Intersil EL7560. Does anyone have a source
for cheap photocells?
Mike