Updated May 2017

Solar Equipped RVs

We personally drove our solar equipped RVs some 130,000 km over most of Australia’s inland dirt tracks. Nothing failed in that distance (and 20 years).

Our solar equipped RVs – VW Kombi

Of our solar equipped RVs, the first was a now rare 1971 VW Kombi Westfalia camper that we modified for extensive Australia dirt road usage. We mounted the single Solarex 80 watt solar panel on a tilting base. A basic solar regulator controlled solar input to 100 amp hour battery. The battery could also charge, via a voltage sensing relay, from the VW’s alternator.

Kombi tilted module

The trustworthy VW Kombi and my wife (Maarit) just off the Strzelecki track – camping overnight. Pic: solarbooks.com.au

This powered a 40 watt Engel chest fridge plus internal and external lighting via three 20 watt halogen globes. Only two were used simultaneously. Solar back then was very costly. It was far less than I now advise, but it worked well as we travelled in areas of ample, reliable sun.

The Kombi was 100% reliable over some 25,000 km of mostly corrugated dirt tracks. These included the Birdsville, Oodnadatta and Strzelecki. Its low slung engine however precluded deep water crossings. Further, a Kombi is all but impossible keep straight line on soft mud tracks. I sold it a a few years later and bought an OKA ex-mining truck.

Our solar equipped RVs – the OKA

OKAs are Australian 5.5 tonne 4WD trucks for fully off-road use. Some 550 or so were made from 1993 to 2010. Production then ceased. They are now sought after as stunning go-anywhere vehicles. Even after several hundred thousand kilometres they sell for well over their new price! Ours was a 14 seater coach-bodied version – made in 1994.

Adobe Photoshop PDF

The OKA crosses Wenlock river on the track to the tip of  Cape York. The white dome is the antenna for its satellite phone. Pic: solarbooks.com.au

I replaced the roof by a fibre glass pop-top. Also, I stripped the interior and built a dinette/double bed plus kitchen. The entire powder-coated white aluminium interior weighed under 75 kg. I also installed twin 220 litre water tanks, two 210 litre fuel tanks, a second spare wheel and a firewood rack.

The alternator, I replaced by a Bosch 140 amp unit. This charged the 400 amp battery bank via an early smart alternator regulator and voltage sensing relay. I mounted two 100 watt Solarex solar panels on the cab roof, and installed a Plasmatronic PL20 regulator.

Main loads were a 71 litre eutectic Oz Fridge and a Westinghouse satellite phone/fax. The latter was as big as large suitcase. It weighed over 15 kg. Its dome antenna can be seen (above). I also installed 12 (switchable) halogen globes of 10 and 20 watts each.

Our solar equipped RVs – the OKA in use

We used the OKA extensively, driving across Australia (via Alice Springs) from our then Broome home (All Solar House) to the east coast and back. We did the return trip (about 13,000 km) 12 times in the OKA. And three more times with its successor. Some 80% of each was off-road.

The Westinghouse satellite fax/telephone was 100% reliable – but energy hungry. I replaced it in 2002 by a hand-held version. This reduced energy draw, enabling us to slash battery capacity to 120 amp hours.

Whilst ideal for long distances off road, OKAs are too large and unwieldy for everyday use. We reluctantly sold it to a Queenslander – who drove it home. He later restored it superbly.

How the OKA looks now.

Our solar equipped RVs – Nissan Patrol/TVan

We replaced the OKA by one of the last 4.2 litre TD Nissan Patrols, and a TVan.

This time I went all solar. I designed and installed it as a self-contained system for each. The Nissan’s two 100 watt solar modules charge a 110 amp hour AGM via a PL 40 regulator. The alternator does not normally charge that battery. If needed it is done via a switched voltage sensing relay. Its main load is a 60 litre Engel fridge. It also drives a single outside light.

Solar TVAN and Nissan Mitchell Falls

Nissan Patrol and TVan at Mitchells Falls (in Australia’s far-north Kimberley). Pic: solarbooks.com.au

The Nissan also had the very first Redarc BMS 1215 Battery Management System. This, (unit 0000001) on three year off-road trial, was powered from the Nissan’s alternator. It drove a dummy resistive load, working superbly over very rough 75,000 km. It still lives today – charging a battery for outside lighting.

The Tvans roof had a 50 watt solar module. This charged a 100 amp hour AGM battery via another PL20. Its load: – two 5 watt LEDs, an external 5 watt LED, water pump and a diesel-powered heater. It also drove a laptop computer for Telstra Next G. When ultra-cold it drove a 12 volt electric blanket for an hour or so. The load? Less than 20 amp hours/day.


Plasmatronic PL20 indicates a comforting 12.5 volts (in the TVan). Pic: solarbooks.com.au

The two systems could be interconnected – but never needed.

Our solar equipped RVs – Nissan Patrol/TVan in use

The Nissan/Tvan solar worked so well I strongly recommend the approach. It is particularly good for 4WDs towing camper trailers. It requires roof space for the solar. But the more one travels, the less one tends to carry. After a year or three we always had ample space left over.

All three of our solar equipped RVs worked without any problems over a combined 165,000 km. Of that, over 100,000 km was on Australia’s badly corrugated dirt tracks. Often in 36-40º C.

Collyn’s Books

Collyn Rivers’ books include the all-new Caravan & Motorhome Book, the Camper Trailer Book, Caravan & Motorhome Electrics, Solar That Really Works (for boats, cabins and RVs) and Solar Success (for home and property systems).