Solar charging-personal versus central etc.
Stan. SWAN
stan.swan at gmail.com
Wed Jul 30 23:01:33 EDT 2008
Scott- thanks for the informative reply. I've long been an enormous PV
fan- you couldn't really ask for a better technology- and have become
even more so with global energy hikes, & the arrival of CIS/CIGS PVs.
Low voltage,long life & rugged ultrabright white LEDs are now
threatening to make CFLs obsolete too. Your "20 years of electricity"
comment needs qualifying, as with just ~10 years of storage battery
life means at least one battery bank replacement in that time = $$$$
extra.
I favour both centralised AND personal solar power, as it's all too
easy in many communities to get "off side" with the guys controlling
resources.You know how these things can go no doubt, especially when
tribal issues arise. A supply fuse my inconveniently "blow" just when
you want a top up...
Additionally XO use surely means colossal inconvenience having to walk
into the village (with all it's distractions) & wait 3 hours just to
charge the battery. At weekends especially kids could be helping at
home & have a simpler & slower (maybe loaned) personal solar charger.
I'd be very focused on a SLA battery being initially PV charged too,
as having to leave an XO itself out in the sun may mean theft,
accidental damage or even ruination by rain/wind. Personal chargers
are achievable right now & proof of concept tweakable, while larger
centralised ones require much planning & huge finance.
Long range WiFi? I modestly point to my celebrated =>
www.usbwifi.orconhosting.net.nz which outlines field work & cost
effective enhancements. Almost ANYTHING in the LOS path of 2.4GHz
signals will attenuate them. Are you factoring this in?
To conclude- lets not forget laptop power needs are falling
drastically! Intel Atom powered "netbook" offerings are increasingly
thick on the ground,& many run for 6-8 hours per charge. Laptop
charging energy may decrease at much the same rate as have cell phone
power needs over the last 15 years. My first calculator in 1973 ran
for 3 hours per charge, yet most modern offerings (infinatly more
powerful) run for months/years on a few AA cells.
Stan
---------------------------------------------------------------------------------------------------------------
Stan. SWAN - Educator/writer/consultant (ICT-Electronics-Sustainable Energy)
EMAIL: => stan.swan at gmail.com & (Work) => stan.swan at weltec.ac.nz
CELL: (64)-021-672-958 HOME: (64)-(4)-562-7494 GST Reg: 36-921-021
POSTAL: 24 Tuatoru St, Eastbourne-L.H., Wellington 5013, NEW ZEALAND.
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