The truck
Due to limited time and talent, the decision was to go for a renowend builder. After visiting several builders we felt most comfortable with UNICAT, especially as the project lead had very similar ideas on the build of the truck.
The dimension of the self-supporting all-composite body is 5,500 × 2,480 × 2,205 mm (L×W×H) on the outside.The shell is constructed from 60 mm sandwich panels: 3 mm FRP outer skin over polyurethane foam core with 2 mm FRP inner liner, cold-bridge-free throughout, and rated at 0.44 W/m²K thermal transmittance. The floor panel (100 mm) carries an integrated steel frame which interfaces with a torsion-free 3-point kinematic subframe, decoupling the rigid box from the flex-torsion dynamics of the MAN chassis on uneven terrain.
Water 600 litres across two independent fresh water tanks, greywater 148 litres; blackwater holding is 130 litres — both tank evacuation valves are pneumatically operated, heated, and dischargeable from either cab or body. Fresh water is filtered and cleaned using 0.2µm ceramic filter / activated carbon filter, the first one removing all bacteria and microorganisms, the latter one dissolved impurities like pesticides, metals or chlorine; capable of rendering surface water into hygienic drinking water. Any post filling contamination would be treated with high density UV-C prior to the usage.
DC Power is supplied by a 8 LFP batteries 12.8 V 200 Ah (a total of 7.6 kWh usable), charged via the chassis alternator (110 A), with a 5 kW continuous / 9 kW peak inverter-charger providing uninterrupted AC (plus full redundancy). PV system with 2.1 kWp more than sufficient to keep the batteries full with normal usage.
Kitchen is equipped with a fridge incl. small freezer, two induction fields and an oven incl. microwave). Completed is the list of electrical appliances with a Miele 8kg washer/dryer. Coffee, my essential fix in the morning, is made in a simple yet genius espresso machine (Superkop), using no electricity. You only need a water boiler and a hand coffee mill to enjoy a good espresso in the morning. It takes some time to get the ideal ground and the right filling but then it is as good as any espresso from a high end, heavy and space consuming maschine. I got that as a gift from my former staff at Aurubis, reminds me of the time spend there in a pleasant way.
Heating is a 9.0 kW diesel-fired central system with altitude compensation, feeding radiators in the living area, towel rail in the shower, and underfloor bed heating — backed by a full antifrost package for the water systems. 24V aircon max. 3.5 kW cooling capacity keeps the box cool, can be switched on from the driver seat.
Sleeping is in the back on a 2000 x 1500 mm Matress with a sliding door for separation from kitchen / dining. The dining table can be lowered and converts to a second bed of 2000 x 1400 mm for guests.
The whole assembly sits on a MAN 18.320 chassis with 4500 mm wheelbase at around 14 tonnes: overbuilt for the job, but you never know when you need it. The floorplan is optimized for weight distribution. The 600l water and the 800 Ah batteries are placed under the sitting area bringing the heavy components to the front and improving the weight distribution. The separate shower and toilet has ample space and can be used to dry clothes while driving. While this setup has less of an open space feeling than e.g. putting the sitting area at the back against the bed, it avoids a tail heavy vehicle. Off road performance depends a lot on weight distribution and from the limited experience (individual 1 day off-road training by Tufa) the vehicle has a very good maneuverability in off-road terrain.
