Colin lives on a beautiful property in the hinterland around Byron Bay in Northern NSW.
Their house is grid connected with a tesla battery. Further away however, they have a large equipment shed and workshop, a luxury guest house and are in the process of building a further 6 guest cabins in the same vicinity, all of which all need a constant source of power.
With energy prices on the increase, Colin opted to install a large off-grid system.
After undertaking an extensive load profile, it was determined that they would consume approximately 80kWh/day on average in Summer, and ~90kWh/day on average in Winter; In addition to this, under full occupancy of the guest accommodation the maximum continuous load demand is estimated to reach upwards of 15-20kW, with potential surges as high as 30kW for short periods;
As such, we were able to custom design an off-grid system to meet these needs.
The system design included:
- 1 x Selectronic SPLC1202 (1-phase 120V battery inverter/charger with a 20kW continuous output rating + impressive surge capacities)
- ~250kWh worth of German made, BAE VRLA batteries, with an estimated average daily Depth of Discharge (DOD) of ~20%. This will not only ensure an extremely good Cycle Life, but also provides excellent levels of ‘Autonomy’ for periods of increased demand or extended periods of bad weather.
- ~32kW of solar PV, split between the equipment shed roof and ground mount array (GMA) frames situated south of the shed. The PV is ac-coupled to the system using Selectronic Certified (SCERT) inverters from German manufacturer Fronius. This is estimated to produce approximately 150% of demand, however more relevantly this is estimated to be more like 120% of demand in winter on average, which means there will certainly be increased demand weeks or poor weather weeks when a backup generator will be needed for any PV shortfalls.
- The system also incorporated a 30kVA Himoinsa Diesel generator for backup and redundancy. Although the load profiling might indicate that this will rarely be needed, it is an important investment, especially for applications when demand is in the hands of guests and can’t be managed as easily.
The whole system was custom fitted on site, in an equipment room inside his shed, instead of our standard pre-fab ‘Adapt board’ method.