Old farts and truck batteries

So, strictly speaking, Brian isn’t quite an off-gridder (but lets not split hairs!)

For Perth dwellers Brian and his wife, living (almost) off-grid started after his quest to find fossil-free transport, in his words “for when all the oil runs out”.

Describe your place.Off girder Brian

Our place was build in 1970 and is a double brick and tile 3 bed 1 bath, facing close to North, set on 2,000 sqm and on a slopinghilly block. We have an original 43 year old solar hot water system with electric booster on timer, mains gas for cooking and strictly limited heating.  We also have a slow cumbustion wood heater (yes, the CO2 is ‘closed loop’, not fossil), single inverter reverse cycle air conditioning in the kitchen and ceiling fans elsewhere. I highly recommend people treat their roof with ‘Insulpaint’ as we’ve found it effective.  The grid-connect panels are on the house roof, which has a pitch of about 32 degrees, which I was told was close to optimal average for the year for Perth.  It’s a perfect permanent home for two old farts!

Specs of your system?

We have two systems – the first is a grid connect which started as 1.72kW in 2008, with Fronius 5kW inverter.  I added a 3.8kW in 2010 (when WA introduced 40c feed-in-tariff), all the house roof.  During the 2013-14 financial year, our average daily production was 22.3Kwhrs, while our consumption was 20kWhrs (i.e net export of 2.3kWhrs).

Off gridder BrianThe second is a hybrid off-grid, which was installed in July 2014.  I added 5.88kW which were mounted on the garage roof and connected to a Kaco 6002 5kW inverter and Selectronic SP Pro 481 Controller / inverter; it’s a 48v system.  Our batteries are 8 x 12 volt truck batteries and I have short term plans to add another 8.  In 3 to 5 years I’ll look to purchase better cheaper batteries.

Just a note on my battery cost / source.  I have a mate in the truck business. Big trucks run on 24 volts from 2 x 12 volt batteries. When one fails, they don’t mess about, they replace both. This can mean that the non-failed one still has ‘life’ in it. So being a kind-hearted person, I give these a home! Cost?  Zilch, other than the odd Corona.  In the long term, I will be looking for Lithium battery packs from battery electric vehicles that are below par for a moving vehicle, but this would not matter for a stationary application such as ours.

Has going (almost) off-grid compromised your lifestyle?

Off gridder BrianMy renewables adventure started in 2007 when I was looking for fossil-free power (both vehicle and energy supply) to use when oil runs out.  I started with an all-electric motor bike, and a 1.72kW solar system on house. It’s just kind of snowballed from there!  The bike now has 65,000 kms on the clock, all powered by solar and in 2012 I bought the all-electric Nissan LEAF, to replace my wife’s old clunker.  This has now done 15,000 km, again all powered by solar.  As age pensioners, we no longer have electricity or petrol / fuel bills…and we love that.



Off Gridders – Lorna and Ken

OK, so maybe going off-grid does sometimes require small compromises – in Lorna & Ken’s case, a new (and not-as-nice-as-the-old-one) fridge!  The couple got in touch after reading about The Off Grid Solar House in the Sunday Age and have kindly shared their story and a couple of photos of their set up with us.

Tell us about your off-grid house.

“Our home is reliant on cross flow ventilation and over head fans in summer a wood heater and wood fired stove which produces hot water during winter. Our permanent residence is modest but has all the usual white goods plus water pumps for both the house and garden.  We sadly discarded a much beloved double door cafe fridge in preparation for going off grid as it was too energy inefficient.”

Why did you go off grid & how big is your system?

“We decided to go off-grid in April this year primarily because of the area power provider restrictions on inverter size. We were advised this would limit the use of heavy usage items such as large water pumps and electric hot water.  Our panels are ground mounted and through the winter months get shaded 11am to 1pm but the batteries are usually full or near full by then.  Even with overcast weather or heavy fog there have only been 3 days that it did not recharge fully, but not to the extent we needed to externally charge with the back up generator.”

“Our system is 20 SunTech STP250S-20/Wd, KAKP Powador 6002 inverter, Selectronic SPMC241 4.0kW 24V with 12 BAE 1220 Ah 2V battery. We use about 6 kwhr at present which is without the hot water and garden water pump which would double usage. These would be run during the daylight hours to maximise the suns generation so as not to rely solely on the batteries.”

Have you had to change your lifestyle to go off-grid?

“Apart from having to purchase a fridge with wretched plastic moulding going off-grid has in no way compromised our lifestyle. In fact it makes us more confident that we made the right decision. It is also seems a better choice for preparedness for the fire season and we have not gone without any electrical appliances.  After 3 months more than happy with our decision to go off grid just wish the technology was available 30 years ago!  We just find it sad that the excess power can’t be diverted to the local hospital or schools.”