Re: Solar Ideas - long but hopefully informative

[Sebastian Gunner <sebg@optushome.com.au>]

> Anyway, also assuming that we get only 6 hours of full sun per day, the PV
> system needs to provide into storage (batteries) power for the
> remaing 18 hours of the day. therefore, the PV system needs to produce 24kWh
> in 6 hours. That's a 4kW solar panel system!
> It's 40 panels of 100W power ( 40 * $500 = gasp! $20,000) + inverter
> =~$4,000 + batteries =~$500/$1000 + etc. etc.
> It can be seen that  the initial cost can easily exceed $25,000
> 
> Say, a grid connected house was using power irresponsibly as opposed to an
> off the grid house where people
> will tend to be much more thrifty/responsible.
> It is not unreasonable to assume that a grid connected house will spend
> ~$100-$150 a month (like ours).
> Therefore, a $25,000 investment would pay itself off within 150-250 months
> (12-20 years).
> And that's assuming zero maintenance (highly unlikely)
> 
> After all these calculations, does a solar panel system even make sense
> unless its initial cost
> is dramatically reduced or grid-power rates are dramatically increased?
> (hello California!)

There will be others with more direct experience with alternative energy
solutions but I was always impressed with a common sense approach to energy
which is something along the lines of everything that works.  While this is
less appealing to my high tech sensibility some of the solutions it can lead
to can solve many problems.

With you energy consumption what was your water heating?  If it is electric
use a solar water heater.  This obviously is much cheaper and more energy
efficient than PV electric to heat water.  It is simply heat to heat.  If
one of these panels wont quite last through the night get two.  Design a
system that will never need electricity or gas to heat water.  Although gas
is more efficient than electricity (given electricity goes from coal or oil
to heater to pressure to kinetic energy to electrical energy to heat, a lot
of lost energy in transfer).  Depending on the area use wind.  I have seen
some set ups that have not been able to afford the high tech tower and prop
and have instead built there own using 40 gallon drums cut in half down the
length and then reset about a third ajar so that when you look down on them
they are in an S formation.  They have placed these on a spindle or vertical
axle and attached a sprocket at the bottom.  When the wind blows they turn
and the kinetic energy is converted to electrical energy with the use of a
generator.  The inefficiency of the drums as a catchment of the winds
kinetic energy was made up by increasing the number of drums in the system,
because they were so cheap.

There is also methane as a source of gas depending on your situation.  One
could bring a community together and join five or more houses in investing
in a methane digester system and use the gas for cooking or power
generation.  The beauty of this is that methane is much more greenhouse
effective (damaging) the CO2 but methane burnt is more CO2 and hence less
damaging.

I know that if someone suggested grouping neighbourhood resources to me I
would find it impractical in my current situation.

I don't have any statistics on these set ups. It may be that they wont work
in you situation but hopefully someone else on the list can chime in with
more direct knowledge of such systems.


-- 
Sebastian Gunner
Em: sebg@optushome.com.au
Em: sebg@iprimus.com.au

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