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Having
fun while setting up our suburban house to run almost entirely on
renewable energy was the aim and doing it with recycled materials
and within the limits of a standard rental agreement was the
challenge. Three months and lots of fun later it is fully up and
running. Here’s our little story.
It
all began when I was renting a small two story townhouse in a large
complex. I had just inherited a free new 40W Solarex solar panel
after someone at work had burnt a hole through it with a magnifying
glass (trying to see if it would increase the output). Seeing as I
got the panel for nothing I decided it was time to see what it is
really like to use a renewable energy system in the home. This first
system ran the upstairs lights, and stereos of my then housemate and
myself Steve Sertis.
The
initial system consisted of the Solarex 40W panel (the hole did
little to affect output), Six 40Ah 12V gel cell batteries in
parallel, a Plasmatronics PL20 solar regulator, and a SEA 450W
sinewave inverter.
The
batteries I got for free from the local wheelchair repair clinic.
Battery powered wheelchairs often came in from country patients with
batteries that weren’t necessarily dead but were changed because
it cost so much to get the chair in again. The result is a lot of
fairly good to very good FREE 12V deep cycle batteries. I’d just
go through the pile with a multimeter and a large halogen globe to
load them up and check the loaded voltage before picking the good
ones. They were installed all in parallel in a plastic box in my
bedroom with lots of vent holes. I really feared a leak onto the
carpet but the gel cells were never really going to be a problem. It
turned out that six large batteries in parallel with one 40W panel
is not very good as their is never enough solar power to equalise
them and so in time they wouldn’t hold charge as well. I ended up
putting 30A switches between three lots of two in parallel. This was
much better.
The
plasmatronics solar regulator is about twice the cost of other
standard ones but its functionality and ability to readout the
performance of the system day by day makes it a rewarding choice. It
was exciting to come home and see how many Ah came in from the solar
panel that day and therefore exactly how much we could crank the
stereo’s up that night.
The
SEA inverter was chosen
because it was moderate in capacity, had no risk of producing hum on
the stereos and is reasonably priced. It has never stopped working.
The supply frequency however isn’t exactly 50Hz. Therefore any
electric clock that needs 50Hz to keep time won’t work very well.
Over a week my little innocent looking red numbered bedside clock
radio lost time and I missed several early morning trains to work
before realizing what was going on. In addition to loosing time I
discovered that it uses nearly 10Watts so it will probably now spend
the rest of its days in clock radio heaven.
The
solar panel mounting was hardest thing. The sunniest site was on the
back carport but that being on the opposite side of the building to
my bedroom was obviously not ideal. I was also afraid of it blowing
away and landing in the next-door neighbours kitchen. After much
procrastination I mounted it on the carport roof with clamps onto
the vertical fins. For extra storm protection I added of wire
fishing trace that fixed the panels to large washers were epoxy
glued onto the metal roof. In hindsight this was a bit of overkill.
The power cable then ran over the roof and into my bedroom on the
second floor.
This
basic system operated for about six months without a problem until I
decided to move in with fellow enviro freak Dennis Stanley who was
renting a house not far away. Well before the move there was much
talk of grand plans, this time to also include a wind turbine and
biodigestor.
The
Leederville Experiment
I
had been living in the Leederville house for some time and had a Permaculture
garden on the way. I was really interested in Julian's set-up. We
had similar ideas so he moved in and the project went ahead.
From
the moment Julian moved in we were on a mission to see how far we
could go in a rented house. We wanted, I guess, to set a bit of an
example but also to see if we knew as much about this stuff as we
thought we did. I, Being the leaseholder, was acutely aware of the
position of renters. We have special considerations. We can’t
interfere with the property. No drilling, no cement footings etc. As
a renter you tend to move around from property to property at the
whim of your landlord so any energy system has to be portable. A
more subtle consideration is that not being a property holder you
have little sway with the authorities. On the first mention of any
complaints from neighbours or alike it is much easier for the
landlord jut to ask for it all to be taken down. So considering any
negative impact of the system on others around you is very
important. The positive impact that if we manage to raise awareness
of these issues then perhaps their children will have a cleaner
world in which to live seems too distant. With these considerations
we began our mission.
The
AIR403 arrived early and the specs called for a whopping 400 Ah of
battery storage. We had a forklift at work and I had previously
salvaged some batteries from it so I approached the forklift company
for some more. They were very helpful. It turned out the guy’s
wife had done some work at the environmental technology centre (ETC)
at Murdoch University and that connection was all we needed. He
showed me a pallet of old batteries and told me to take what I
wanted. I took 12 batteries. With the three I already had I hoped to
find at least 8 serviceable ones. The batteries in question are
Century 12A’s 6v 100 Ah.
I
set about rescuing them. I
got 4 serviceable pairs and housed them in a box made from salvaged
packing ply. Heavy-duty castors, also salvaged, were installed on
the box so moving the batteries around is a sinch.
Then
came the solar panels. We wanted to add to the system that Julian
already had going in Claremont. We got another Solarex 40W from his
work and added a Kyocera 80W from the ‘12Volt Shop’ to take the
total to 160 Watts. I was interested in building a tracker. We
looked around and we were most impressed with the design of a
passive solar tracker that utilised differential vapour pressure to
force a fluid from a sunny vessel to a shady vessel thus upsetting
the balance and tipping the panels toward the sun. We decided to
build the tracking mounting only and get the solar panels up as soon
as possible. A few days at Julian’s workshop and the mounting was
ready. After a trial assembly at Julian’s work we packed all the
nuts and bolts into a paper bag and slowly transported the whole lot
home on the roof racks. I was so confident in the strength of our
system I suggested a good wind test was to drive home with the
tracker assembled, panels and all, on the roof of the car. Julian
thought this was unnecessary.
I
guess as most of you realise motivation is a principle moderator in
any project and this was no exception. We found a cure was to
announce the celebration of our solar system well before it was
ready. At this stage it was little more than some panels in the shed
and a few drawings. Nothing like a deadline I guess. So that evening
was approaching. People were to arrive in only a few hours.
Off
the roof of the car, onto the pergola and lashed down amongst the
grapes with rope. No
drilling or permanent fixtures allowed. The panels were mounted with
only a “little” fuss.
Already
our guests were arriving. No food, not even any light, at this
stage. Still running around with tools and wires we hooked up the
batteries and the inverter and celebrated the installation of our
solar system. The huge irony was of course that because it was
already dark we never bothered to actually connect our panels to the
batteries. The lighting we used all night was battery power,
originally derived from the grid. There, I’ve aired my dirty
secret but first thing next morning we connected the panels and have
been using solar powered lighting ever since. Our guests helped with
the preparation and with a bit of communal cooking a good night was
had by all.
Even
through the dead of winter we have kept our head above water. First
day we got 42 Ah. We average between 30 and 40 and our record in
52Ah per day. We expect much more in summer and hope to even run the
fridge with a new inverter. It has to be said that in terms of
reducing our greenhouse emissions the majority of our savings are
efficiency savings that anyone can implement without needing to go
to renewable energy.
Try
this exercise next weekend. During the day unplug your fridge and
turn off everything in your house the normal way as if you were
leaving the house for the day. Go out and look at your meter. Is it
still turning? This is your phantom load. Caused by appliances using
power even though they are not being used. Now go around the house
unplugging (or turning off with the switch) different appliances one
at a time to find out where your power bill is going. You can
estimate the load by timing how long it takes the disc in your meter
to spin one turn then work out how many spins per day. Divide that
by the spins per kWh, written on the meter and you have your phantom
load in kWh per day. Note that the disc has quite a bit of inertia
and takes a minute or two to respond fully to any changes. This may
sound like a trivial exercise. That’s what I thought. Our phantom
load was 2KWH per day or one third of our bill. Our main offenders
were two stereos left in standby and a halogen light transformer
that was continuously connected to the mains with the 12v side
switched. We now switch all appliances off using the power switch
(rather than just the remote control) and unplug the bad lamp when
not in use. This little effort saves more greenhouse gasses than our
entire renewable energy system and anyone can do it. We also use
energy saver compact fluorescents or standard fluorescents for all
our lighting. The savings you make with these lamps will more than
pay back the expensive purchase price, provided they actually last
as long as the manufacturer claims. My experience here is that you
get what you pay for and spending a few extra dollars for a
reputable brand will be a good investment. Many of our cheap lamps
failed very prematurely. We have had no problems with our Philips
ones.
At
the moment our tracking system is no more than a loop of rope that
you can tie off in any position. That’s what you call “work in
progress ”.
The Air 403 Wind
Turbine and Tower.
The
wind turbine had always been in the Grand Plan but the fear of the
neighbours complaints as well as where we were going to put a pole,
kept it on hold until we at least had a solar system up and running.
Just to make sure it didn’t fall through we bought it early on in
the piece. I recommend this technique in ensuring you follow through
with your intentions, as a $1000 wind turbine lying under the bed is
pretty useless when the batteries are low. It was also around this
time that we recruited Adam Coffee, master welder (he says so
himself), for the tower construction.
The
initial plans were to attach a pole to the out house wall running up
alongside the already existing 6 metre long sewerage vent pipe. We
reckoned that these being of similar height and close together would
make our turbine quite inconspicuous. The logistics of doing this
though were quite a problem. Firstly we would probably need a
concrete footing, which was not really feasible in a rental place.
The other problem was how to attach it to the wall without drilling
and bolting. Our proposed solution to this was called “The Big
Clamp”. It was supposed to firmly attach the tower to the top of
the wall just using rubber, many small and intricately welded pieces
of steel and lots and lots of clamping force. It might have worked
but after many discussions on the steps looking at the wall and over
breakfasts looking at the wall it just seemed like a big hassle and
ended up slowing the project momentum down quite a bit. There was
also the possibility the extra load would push the wall over.
Eventually after months of deliberation one day I just asked Dennis,
“Why don’t we just make a guyed tower and put it at the corner
of the shed”, “Ok” he replied and the decision was made just
like that. So that day work on the tower began.
Our
final design consists of some heavy walled 2.5inch Galvanized water
pipe from a local salvage yard, guyed with three cables salvaged
from Adams bedroom, to three salvaged star pickets belted deep into
the ground. Its base fits into a tube welded to a large piece of
angle iron also belted deep into the ground. Tension in the cables
is adjusted with some simple turnbuckles welded up from several
bolts, shackles and threaded rod. The turbine itself is attached two
meters above the guys to a piece of two inch thinner gauge
galvanized pipe that fitted tightly (with a sledge hammer actually)
inside the heavier pipe. All in all the tower is 7m high, very
sturdy, (thanks to master Adam) and cost $15 and small tin of zinc
rich paint.
Now
the turbine itself has its own story. It was the basic AIR403 Land
Version. It comes as rough unpainted aluminium and looks pretty
industrial. So not being happy with this look, and guessing that the
neighbours wouldn’t either, I took to it with some yellow and
black paint to turn it into what is now known as “Our Bumble
Bee”. Ever since I held it in my arms I knew those sexy curves
could be used for something more.
The
turbine was simply attached to the top of the tower with its inbuilt
clamp system and a piece of rubber for better grip. The wires run
down the inside of the tower and exit midway onto the shed roof
before beginning the 20m journey to the battery box. It was
during the installation of the power cable that we arrived at the
problem of how to stop them vibrating against the side of the pipe
and possibly making lots of noise. And so we discovered a most
innovative use for odd socks. The cable running inside the tower was
carefully wrapped in many of Dennis’ odd socks. One by one they
disappeared down in to the pipe until the whole cable was restricted
from hitting the sidewall. Problem solved with salvaged materials
again.
And
before we knew it, it was all done. The tower was raised, guys were
tightened, turbine connected to the battery, the system was
complete. It was time for another celebration. Little did we realise
that the wind was going to pick up appreciably before the next
morning and we were to awaken to the sound of
whippersnippering in the back yard. But this be not a whipper
snipper, this be our Bumblebee. Yes it is a little louder than we
had imagined and it is not something we will be leaving running
often in a residential area but after installing a large shorting
switch the next day we reckoned that our Bumble-Bee could still be
part of our family.
As
usual we just finished installing the ammeter and switch in time for
the guests to arrive and so communal cooking was the call of the
night once again. But this time it was done to the sweet sound of
the Bumblebee out back and under lights powered by the sun. What
more could one want.
An
End
By
Dennis Stanley and Julian Ilich |
