Street Tree Nursery Case Study:
Off-Grid Solar and
Battery System for
Urban Sustainability
Introduction
In November 2023, the San Francisco Department of Public Works (DPW) implemented a cutting- edge off-grid commercial energy system at the pioneering Street Tree Nursery, an initiative aimed at urban environmental stewardship and community development. Sol-Ark, along with one of its certified installers, led the project, delivering an energy-efficient, sustainable solution for the nursery's power needs. This project not only exemplifies urban sustainability but also enhances the city's green landscape and serves as a model for community-oriented environmental progress.
The Story of Sol-Ark and San Francisco's Street Tree Nursery
With over a decade of expertise in the off-grid energy space, Sol-Ark has been at the forefront of innovative energy solutions, supporting projects that align with sustainable development and environmental stewardship. When approached by San Francisco’s DPW to develop a renewable energy solution for the Street Tree Nursery, Sol-Ark provided a system that would enable the nursery to operate independently of the grid. Utilizing a 30kW solar array paired with the robust Sol-Ark 30K- 3P-208V hybrid inverter, the project was designed to meet the nursery’s needs efficiently while promoting sustainability in urban infrastructure.
The Challenge of Sustainability and Energy Independence
The Street Tree Nursery faced unique challenges in implementing a renewable energy solution:
Utility Line Costs: Extending utility lines from PG&E to the nursery location would have incurred substantial costs, making it imperative to find an off-grid alternative.
Urban Environmental Goals: The project needed to align with San Francisco’s broader sustainability goals, enhancing urban greening while minimizing carbon emissions.
Educational Programs: The nursery, also functioning as an educational center, required a reliable power source to support its training programs and day-to-day operations.
Why San Francisco
DPW Chose
Sol-Ark
To address these challenges, the San Francisco DPW chose Sol-Ark’s advanced 30K-3P-208V hybrid inverter system for the Street Tree Nursery. Sol-Ark was selected for its:
Proven Off-Grid Expertise: With extensive experience in off-grid installations, Sol-Ark provided the ideal solution to ensure reliable power without the need for utility line extensions.
Efficient Energy Management: The 30kW solar panels, coupled with 62 kWh of energy storage from Deka Duration HV ESS, provided a balanced and efficient system that met the power demands of the nursery.
Cost-Effectiveness: By opting for a renewable setup instead of extending utility lines, the project saved over $60,000 in potential utility costs, demonstrating both financial and environmental benefits.
The Solution - How
Sol-Ark Delivered
The collaboration between Sol-Ark and San Francisco’s DPW resulted in a highly effective energy solution for the Street Tree Nursery:
System Configuration:
Solar Array: 30 kWdc solar array utilizing a Sol-Ark 30K Hybrid inverter.
Energy Storage: 12 Deka Duration HV ESS providing a total system capacity of 62 kWh for off-grid power needs.
Application: Off-grid power for both the nursery and its educational programs.
Cost Savings and Sustainability:
Avoiding Utility Costs: By implementing an off-grid solution, the nursery avoided over $60,000 in costs associated with extending PG&E utility lines.
Carbon Footprint Reduction: The solar energy system significantly reduced emissions typically associated with conventional energy sources, aligning with the city’s broader environmental goals.Community Impact:
Localizing Production: The Street Tree Nursery reduces the operational and environmental costs associated with transporting nursery stock from distant locations, further contributing to urban sustainability.
The Results
The Street Tree Nursery project has set a benchmark for urban sustainability, enhancing environmental stewardship and operational efficiency:
Sustainability and Carbon Reduction: The off-grid system reduced the nursery’s carbon footprint, providing reliable power while supporting the city’s greening initiatives.
Economic Viability: By avoiding costly utility line extensions, the project highlighted the financial viability of using off-grid solar energy systems in urban settings.
Community Resource and Education: Beyond powering daily operations, the nursery serves as a valuable community resource, providing training and career pathways in green jobs, and demonstrating the power of renewable energy to create local opportunities.
Together, these elements make the Street Tree Nursery an exemplary model for cities worldwide. By integrating solar power with eco-conscious operational practices, San Francisco has demonstrated the effectiveness of renewable energy in achieving comprehensive sustainability objectives.
Powered by Sol-Ark’s dependable technology, the nursery not only operates more sustainably but also serves as a beacon of environmental stewardship and community development.
