Taft-Ojai Botanical Garden, part of the Canyon Nature Center, in Ojai, California (US) draws visitors from around the world to walk the beautiful paths and see a unique collection of Californian, South African and Australian flowers and trees. The gardens are at the end of a long, dirt road and are somewhat of a secret—as the garden is only open by appointment. However, the Nature Center recently opened an “eco-lodge” where visitors can stay and enjoy the beautiful surroundings.
Because the garden and nature center are focused on the environment, the goal of the solar installation was to dramatically reduce generator use and fuel consumption, eliminate trenching transmission lines and use non-toxic and non-hazardous energy storage. The property previously only had a temporary power setup. “Energy management and efficient design is the key to successful off grid living,” said Cam Campbell owner of CSE. "The Taft property was not originally designed to be off grid so we had to work hard with the venue operators to mitigate and manage their energy use."
Managing the full range of needs
The key to the successful installation was managing not only the everyday function of the facility, but the range of needs during the different functions that are held on the site. Some of the steps taken and considerations included increasing the number of batteries being added to the system, changing existing lighting to LED, establishing best practices for using equipment such as large existing AC units and providing basic guidelines for visiting planners of events such as weddings to help them understand the energy limits of the property.
At first it was difficult to determine the exact needs of the facility because the facility hosts a variety of events, and it was not simple to assess what type of power needs the facility could require. In talking with the Taft team, CSE recommended adding battereis to manage the range of different power loads that the facility should be able to handle.
The solar system installed now provides efficient power for the Taft Pavilion and facilities, event and education spaces including multiple rooms, outdoor lighting and fountains.
Other minor challenges included plan adjustments to accommodate oak trees in order to secure the appropriate permit with the County of Ventura. Because they were required to leave the oak trees where they were, the solar panels had to be installed further away, which necessitated greater trenching. But it was an obstacle that was easily overcome.
The system includes 36 ground mounted SolarWorld Sunmodule SW270 panels on Prosolar mounts. There is 1 SMA SB9000TL-US-22 and 2 SMA Sunny Island-6048 inverters. Approximately 9.72kW of electricity will be generated by the system annually. The energy is stored in 8 SimpliPhi PHI2.6 kWh batteries, which provide 20.8 kWh of stored power.
With Taft Gardens, it was evident that the PV generation far exceeded their daily loads and the battery storage capacity. In a second installation, California Solar Electric installed 16 more PHI2.6 kWh batteries provide 41.6 kWh of stored power.
The SimpliPhi batteries are lithium ferro phosphate (LFP) batteries, which were chosen because they have a proprietary cell architecture, power electronics and a built-in battery management system. The batteries don’t require ventilation and cooling and can be strung in parallel (not in a series like lead acid batteries), thus allowing the customer to increase capacity without increasing the voltage. Therefore, increasing the battery storage with Phase 2 allowed them to capture all their generation, maximize their capital investment and store more power for evening loads and greater autonomy – all off grid.
Written by Anne Fischer, Managing Editor, Solar Novus Today