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Client:  Waialua High School
Location:  Oahu, Hawaii
Application:  Hybrid Off-Grid

The Hawaii Department Of Education (HIDOE) had a problem: rising temperatures, antiquated electrical infrastructure and the need for air conditioning in schools.

In Hawaii classroom temperatures can exceed 38°C, creating challenging learning environments. However estimates to install traditional grid-tied cooling totalled $1.695 billion.

HIDOE began piloting innovative solutions that could cut that cost: off-grid photovoltaic + battery air conditioning systems. Estimates for this solution were approx $140 million – a fraction of a traditional network upgrade.

The Solution

Simpliphi’s non-toxic and safe storage solutions were integrated into hybrid off-grid solar PV + battery air conditioning systems for classrooms at Waialua High and Intermediate Schools.

These systems create energy independence and decrease costs, freeing up funds that can be rededicated to support curriculum and learning resources.

In partnership with Haleakala Solar and Ameresco, 21 outdoor rated cabinets with 7-10 SimpliPhi PHI 3.4 batteries and Outback Inverters were installed DC coupled to distributed solar arrays.

Each cabinet has the capacity to increase the battery system, which is a unique advantage of SimpliPhi’s modular approach to energy storage. Over 140 batteries (~500 kWh) are operating these air conditioning units today, and more systems are coming to schools statewide.

simpliphi-power-phi-3-424V and 48V PHI 3.4 kWh Smart-Tech Battery

  • Integrated Battery Management System (BMS) protection
  • Compatible with all industry standard inverter/charge controllers
  • Operating temperature 20° to 60°C
  • 98% efficiency rate
  • No ventilation or cooling required

Download a printable version of this case study here

For enquiries about our range of SimpliPhi lithium batteries or Outback inverter chargers please enquire here or call +61 (3) 9696 1119.