[LINK] [PRIVACY] BT: 'Are meters too smart by half?'

[Tom Koltai]

> -----Original Message-----
> From: link-bounces at mailman1.anu.edu.au 
> [mailto:link-bounces at mailman1.anu.edu.au] On Behalf Of 
> Richard Chirgwin
> Sent: Saturday, 26 June 2010 6:35 PM
> To: link at anu.edu.au
> Subject: Re: [LINK] [PRIVACY] BT: 'Are meters too smart by half?'
> 
> 
> I'm resending this without the previous post because something is 
> scrambling in the fonts.
> 
> I have some friends in the Southern Tablelands who have never been 
> "on-grid". The place was solar from day one, mostly because that was 
> cheaper than getting someone to run a line several km for the grid 
> connection. The only missing "mod con" is an air conditioner.
> 
> In what way is a system like that not sustainable?
> 
> RC
> 

At 15% or below electricity efficiency, a cost comparison is appropriate
- and is compared with city Grid pricing kWh.

Capital replacement cost of Solar Panels, every 6 to ten years. (I don't
care what they say in the manufacturing brochure. Anodization results in
eventual replacement!!! Anodization is an effect of acid rain and
electricity generated. If you live in a city, then your rain has a lower
PH than if you live in a non power station polluted rain area.)
Maintenance cost of replacement parts and cleaning of the solar panels
(Bird residue, dust storms etc)
Battery replacement cycle for a home with 2.3 kids averaging 3.45 kwh
per day (18 mths - 36 months depending on whether dry or wet cell
batteries are utilised - if a compressor based refrigerator or aircon is
used, chop those numbers in half).

If on the other hand, one is prepared to accept 12V fluoro lighting,
solar hot water with no electrical water heating required, gas cooking
opposed to electrical hotplates and oven, then yes, a compromise
efficiency scale can be reached, but not really comparative with city
living standards. 

There is only one, in my experience, cost efficient alternative power
system and that is mini-hydro, if one is lucky enough to live near a
stream.

Combining alternative energy systems appears to be the winning
combination of capital cost efficiency and stable output power
resulting...

E.g.:  Wind, methane/turbine and solar together can be installed for an
individual home for around 32 k (USD$ approx).
The batteries will need replacing every three years (maximum) and wet
cell appears more reliable than dry cell.

Maintenance costs for the three energy systems total approximately 1800
per year.

Currently that exceeds grid power charges... Well until July 1st that
is... After which it might be worthwhile recalculating.

A lot of my data into solar comes from utilising it between 1984 and
1994 in Darwin, NT. At that time of course, Solar panels operated at
efficiency levels sub 7%. Even with the long tropical days and higher
number of sunshine days.

Anecdotally, we did manage to run one 5200 BTU (small) aircon in a
bedroom for 12 hours per day, but it killed the batteries and we were
replacing them every 12-13 months.


What many forget is that modern digital componentry requires stable 60
Hz sine wave power supply.
The requires an additional USP AC filter that comes in at $1200 dollars
(per 300 watts) and requires it's own batteries separate to the inverter
batteries.

Anyone ignoring this requirement will end up with lots of dead pixels on
their LCD screens and failed hard disks and power supplies on their
computers.

Living off grid successfully is hard AND expensive. Sustainability
determination is often dependent on costs not immediately apparent in
the basic setup and running costs. In my earlier email I suggested that
solar systems that didn't operate at a minimum 15% efficiency were
unsustainable. I would like to add the following qualifying words to
that... "IMHO"

My experiences include alternative energy projects in several countries
globally, including Jabiru, N.T. solar; Nevada (geothermal) & Solar;
Nauru, Solar and evaporative, Hungary, PBMR and here in Aus, AJ Bush and
Methane powered Capstone Turbines.

Tom