Construction and mining equipment giant Caterpillar and its dealer network have commissioned solar-powered site workspaces to reduce operational costs and increase sustainability.
The towable, communication-ready, mobile workspaces which include office and kitchenette can be operational within twenty minutes of delivery.
Built by NowStar who are based in Columbus Ohio, the solar powered workspaces feature a quiet, climate-controlled area for five to ten occupants. Insulated walls and energy recovery ventilation reduce power consumption during winter and summer alike.
Currently two models are available: the 28 foot StarPod28; and 36foot StarPod36. Designer inspired, with engineered function, all units include elevated features that feel more like the creature comforts found in brick-and-mortar offices
Caterpillar – in partnership with NowStar – wished to explore practical alternatives to traditional diesel-powered site offices used on construction sites. Conventional units rely heavily on generators which produce noise and fumes. The StarPod28 prototype was intended to demonstrate how a mobile office could function with lower fuel use and reduced environmental impact. It has a 4kWp roof mounted solar array, and a further 1kWp array has been installed on the front elevation of the unit which in this instance is stylised to match Caterpillar branding. 20kWh of energy is stored for 24 hour operation.
The power system for these site offices were designed and installed by Victron Energy distributor Off-Grid Power Systems who have offices in Ohio and Montana.
OGPS evaluated the electrical loads, space constraints, expected operating conditions. Key to the design was to maximise solar production on a relatively compact trailer whilst maintaining the unit’s visual and structural requirements.
The power system includes:
- 2x Quattro 48/3000 inverter/chargers
- 1x Autotransformer for load balancing
- 10x Hyperion roof-mounted solar panels at 400W each
- 4x Merlin Solar TBS240L vertical panels
- 2x SmartSolar MPPT charge controllers 250/100 for the roof; and a 150/35 for the front elevation
- Lynx power distribution
- 4x Pytes V5° heated lithium batteries providing 20 kWh of storage
- 1x Cerbo GX with GX Touch 70 display for monitoring and control – both on site and remotely using the free to use Victron Remote Management platform VRM
A 9 kW dual fuel generator is included in the power package to guarantee winter operation and during extended overcast conditions. If low battery state-of-charge is detected the generator will start – and stop – automatically, prompted by the Cerbo GX communication centre.
Given the unit’s insulation level and the efficiency of the heating and cooling systems, generator run time is expected to be limited, but the backup system ensures continuity whatever the weather.
Follow up orders and enquiries from other off-grid construction sites prove that the design is successful.
