CEC Solar Awards finalist

Shalom Catholic College, Bundaberg, Queensland

CATEGORY: Over 240kW

Kurt Elvery of Elvery’s Electrical Service and Dhayan Nadarajah of GEM Energy

If a client wants to install 810kW of solar PV to help them transition to 100% renewable energy it helps if they have plenty of daytime load and either a very large roof or spare land for a ground-mounted system. Shalom Catholic College in Bundaberg, Queensland, fit the bill.

“The client was aware of battery storage and was broadly interested in it, but was mainly focused on the rooftop PV,” says GEM Energy marketing manager Phoenix Shaw-Collery. “After we concluded that the roof profile of the school was too complex to host a system big enough to cover the needs of the school, we opted for a ground-mount system with a large amount of battery storage.”

The system installed at the school is made up of 1,976 Canadian Solar HiKu 410W modules, 26 Fronius Eco inverters and an Arctech ground-mount single-axis tracking system, along with a 1,160kWh Tesla Powerpack battery energy storage system.

The Tesla Powerpack battery storage solution, before a room was constructed around it that also houses the inverters.

The Tesla storage system is the first privately owned battery system to be engaging in the FCAS markets. It covers night-time load and has enabled the school to hit its target of 100% renewable energy.

GEM Energy has installed tracking before and admits it presents challenges. “A range of materials and installation techniques were used to maintain the quality and integrity of this demanding solution in compliance with international quality standards,” Shaw-Collery tells EcoGeneration. The Arctech tracking system was designed in conjunction with Canadian Solar and uses nylon flexible conduit “Flexicon” for mechanical protection.

The field that contains the PV arrays was surveyed to make sure shading was completely avoided, even between 9am and 3pm on the winter solstice. On average the system is 90% self-sufficient and the client is generating over 130% of energy requirements.

VPP trial participant

Bishop Michael McCarthy and diocesan director of Catholic education Leesa Jeffcoat bless the system before it is commissioned.

In partnership with Hydro Tasmania and Tesla, the Cath Ed Rockhampton BESS Portfolio is part of AEMO’s VPP demonstration program, to test how distributed energy resources can be effectively integrated into the National Electricity Market to respond to frequency variations and balance supply and demand on the grid.

During weekends and school holidays the solar and battery system powers the utilities within the school, such as the server room and cold rooms, Shaw-Collery says. “The batteries still participate in FCAS and the solar exports into the grid for a small feed-in tariff.”

As the system covers a significant amount of the school’s load GEM Energy was able to re-classify the site to a small-business tariff. Now that the school consumes less than 100MWh per year from the grid, it will never pay more than $25,000 a year in grid consumption (although it will take about 12 months to have the tariff reclassified).

As the school is in wind region C, a one-in-portrait configuration was recommended. The 3,000 trees removed to make room for the solar system were replaced with 3,300 native trees and shrubs planted in the Yarra Yarra Biodiversity Corridor in Western Australia, through a partnership with Carbon Neutral and the Plant-A-Tree Program.

“The ground-mount solution allows students to tour their school’s energy plant,” Shaw-Collery says. “The system specifications and performance can also be integrated into science, environmental, engineering and mathematics curriculums at the school. Students can point to the school’s project as an example of a successful transition to renewable energy.”