permaculture

[Chad Knepp <pyg@galatea.org>]

I think the key to an ecological balance regarding electricity will be
found more by addressing the issues around how and how much
electricity is consumed than by the specifics of its generation.
Electricity is a very high grade energy and the ease of which it can
be applied has made it the energy of choice with its subsequent
demand.  The modern home can be run completely off electricity and in
affluent countries many homes are.  Electricity is the magic behind
convenience.

I currently live in an eco-village that does not permit grid
connections so within 200 feet of where I'm sitting are 5+ Kw of PV
panels and necessary subsystems.  I am distressed by an attitude here
and elsewhere that because something is a green technology or "eco"
than it's not only OK to use, it's encouraged or at least subject to
some cheer leading (Yay, it's solar!).  I see people simply recreating
a lifestyle of modern convenience with solar electricity without
questioning the appropriateness of the lifestyle to begin with.  One
of the positive elements of the high cost of alternative energy is
that economic considerations alone increase consciousness of
consumption and often modify lifestyle choices in a favorable way.  My
experience with most things electrical is that they wear out fairly
quickly.  Surely the disposable characteristic of appliances is worthy
of ecological consideration.  Even in PV systems the panels have the
highest longevity of any component.  Charge controllers and inverters
sometimes do not last much longer than good batteries.

I can't really think of anything better than electricity for lighting
and communications, but for most other household applications I think
there exists a more appropriate technology with refrigeration being a
notable and gaping hole.  I think an ice house is a little too much of
a step back but I do think that direct solar/ammonia cycle technology
has tremendous potential (please contact me off list if you have
experience with this).

I guess what I'm trying to say is that the question of whether or not
to PV is only an element of a total ecological assessment.  I think a
more holistic approach which includes evaluating energy use in one's
lifestyle is necessary to truly understand one's impact.  I think I
could prove conclusively with a bit of research that if you took the
average North American and got rid of their refrigerator but continued
to use grid electricity they would have a lower ecological impact than
if they continued their current lifestyle but switched to PV
(including grid inter-tie).

jeff writes:
 > On Wednesday 26 May 2004 10:35 pm, Kelly Finigan wrote:
 > > What this means is: in the future, maybe at some point, if we do
 > > not count the energy to purify the silcon for the cells, the
 > > payback is 3.9 years.  Currently though, it is 15.6 years.
 >
 > <snip>
 > 
 > > Oh, of course, we have to add some more for the batteries (which
 > > wear out and go to landfill or maybe can be regenerated using
 > > more energy), and a bit more for shipping, construction and
 > > finally ripping the system apart to remanufacture it.
 > 
 > In this area batteries can be recycled and are optional for many
 > applications.  We have the choice of utilizing DC directly or using
 > the grid as a battery.  Still, most applications do utilize an
 > inverter along with batteries.
 > 
 > I've been running a typical solar setup with batteries and inverter
 > for about 12 years, and may transition to a DC system.  The
 > batteries are definitely a weak point in solar cell energy systems.
 > When I look at all this from the Permaculture perspective, there is
 > a design shift towards DC applications and a mix of energy sources.
 > This may be the answer.  Look at each site and stay flexable.

Exactly!  Match the application to the most appropriate source of
energy.

 > > Second issue: the panels generate electricity, but I suspect we
 > > need more than electricity to make more panels - we probably need
 > > process heat and organized energy in the form of infrastructure
 > > (to drive cars to modern, ultra-clean factories to make the
 > > panels). Maintaining all this takes energy. Also, every
 > > conversion of electricity into something else (e.g. a PV factory,
 > > road, transport system) is accompanied by an (in)efficiency
 > > factor. If the payback from the PV is even borderline, there is
 > > little left over (especially once the electric transit bus?s
 > > fuel is accounted for) to ?run? the system to create more
 > > panels.
 > 
 > True, we may conclude that PV should not be used for transit
 > applications and encourage local manufacturing.  This transport
 > issue is much bigger than just PV manufacture.  Anyone who travels
 > by air is wasting energy at a outrageous rate.  The energy from one
 > plane trip probably could power a PV factory for several years.

Hmmm... not sure I agree with this.  My research says there is
considerable potential for very lightweight direct solar electric
vehicles.  Think of something like the cars used in the solar races
but much slower, shorter ranged, and with a GVW of less than 500 lbs
(also a 200-300 watt power source/operator).  Electric bicycles are
already becoming very popular in China.  Modern vehicles are sized the
way they are because they need the infrastructure to support the heavy
internal combusion engine.  Electric conversions of modern vehicles
suffer from this design investment and are not the best nor only
choice regarding electric vehicles.

I am in no way a proponent of air travel but I care about accuracy.
Although it's true that planes consume vast quantities of fuel it is
possible to formulate a situation that makes air travel compare
favorably to cars.  According to this site, a fully loaded Boeing 747
gets about 100 miles/gallon/passenger, comparable with a 25mpg car
carrying 4 people and much better than that 12mpg SUV with one person.

<http://travel.howstuffworks.com/question192.htm>

 > > Seems like PV may be a pretty brief evolutionary attempt. In the
 > > big race for ?future-electricity? champion, I would bet on
 > > small hydro, biogas- fuelled generators and rudimentary wind
 > > turbines to outlive the PV (oh, and our old friends wood and
 > > coal). Right now, I tend to think Holmgren is right (at least
 > > until the assumption about lower-energy-intensive silicon is
 > > borne out).
 > 
 > In the desert the local energy source will proably be solar.  No
 > hydro, biogas, wind, or wood.  There may be some wood or coal for a
 > small population, but both wood and coal can become serious
 > pollution problems if not restricted.  In this area we have lots of
 > wood but it does not produce electricity very well.  If we do
 > utilize coal or oil the question might be: Is it less expensive to
 > transport solar cells or oil/coal?
 > 
 > I'm now thinking that anyone who drives a gas eating vehicle has
 > diverged radically from the concept of sustainability and probably
 > from the Permaculture ideal.  Given that we have already made this
 > compromise, it is difficult to be a purist about something like
 > solar cells.  The occasional truck can sometimes be seen in
 > Permacutlure publications, which probably says something about his
 > issue.

Travel is an important and problematic issue for sustainability
research.  Although there is a lot of potential in various
technological solutions, ultimately I think a lifestyle change is
necessary.  The *first world* is addicted to cheap energy and needs a
12 step program or something to awaken us and change our patterns of
abuse;-) 

For those of you that have waded this far through and are really
interested in energy, The Land Institute's Sunshine Farm project
produced an excellent paper (in 2002) about the possibilities of
biofuels (alcohol and bio-diesel) produced on farms replacing current
fossil fuels.  Pay special attention to the pdfs comparing different
energy sources.  I actually draw a different conclusion than
Mr. Bender based on the math but it is a fascinating read.

<http://www.landinstitute.org/vnews/display.v?TARGET=printable&article_id=3dbeba6338ac3>

-- 
Chad Knepp
python -c 'import base64;print base64.decodestring("cHlnQGdhbGF0ZWEub3Jn")'