One Sun Maintenance Services Overview

One Sun provides preventative and corrective maintenance for grid tied commercial and industrial photovoltaic systems in Northern California. Coverage includes Sonoma County, San Francisco, San Jose, Sacramento, North Bay and South Bay service territories with coordination for PG&E and SMUD interconnections. Services target uptime, warranty protection and measurable production gains while meeting NFPA 70E electrical safety and local authority having jurisdiction requirements.

Preventive maintenance and routine inspections

Preventive care begins with scheduled visual and electrical inspections to identify loose connectors, junction box corrosion, framing issues and module soiling that reduces yield. Technicians perform infrared scans, torque checks on PV combiner hardware and DC isolation tests to detect early failure modes. In high soiling areas such as urban San Francisco and dusty Sacramento industrial zones, module cleaning frequency is adjusted based on measured soiling rates and production loss. Vegetation control and roof flashing inspections are included for rooftop arrays in Sonoma County where tree growth can shade arrays seasonally. Battery enclosures and energy storage systems receive electrolyte checks, SOC verification and thermal management audits per manufacturer recommendations.

Performance monitoring, diagnostics and optimization

Real time monitoring platforms are deployed with remote diagnostics to flag underperformance by inverter string, combiner or module group. Data logging of irradiance, ambient temperature and DC string currents feeds automated alarms and scheduled reporting for KPI tracking such as PR (performance ratio), availability and month over month production.

Below is a representative operations summary for commercial systems served in Northern California, showing recommended frequencies, typical cost ranges and expected availability impact.

Task and deliverable	Frequency	Typical cost range (USD)	Typical availability impact	Notes
Visual and electrical inspection with torque checks	Biannual	0.8–1.5 per watt per year	Prevents 1–3% annual unplanned loss	Includes string IV snapshot and combiner checks
Module cleaning and wash	Quarterly to semiannual	0.01–0.06 per watt per event	Restores up to 5–10% yield in dusty sites	Adjust frequency to local soiling rates
Inverter preventive maintenance and firmware updates	Annual	4,000–12,000 per large commercial inverter	Reduces unplanned downtime by 30–60%	Includes fan replacement and capacitor checks
Thermal imaging and IV curve testing	Annual	0.02–0.05 per watt	Identifies hot cells and mismatch that reduce PR	Performed during representative irradiance
Battery health and BMS audit	Semiannual	1,500–6,000 depending on capacity	Preserves storage capacity and dispatch reliability	Includes capacity test and balancing verification

Remote diagnostics use SCADA links and cloud analytics to prioritize dispatch and to justify preventive interventions that deliver measurable returns.

Corrective response, warranties and upgrades

Corrective services include rapid response repairs for inverter failures, module replacement for microcrack propagation and racking repair after storm events. Coordination with manufacturers accelerates warranty claims for panels and power electronics. For large commercial customers, warranty liaison handles RMA paperwork, performance guaranty enforcement and credit recovery with OEMs. Component replacement strategies favor modular upgrades to string inverters or hybrid inverters paired with battery energy storage to improve grid services and demand charge management in San Jose and Sacramento commercial sites.

Safety, compliance, permits and emergency procedures

All field operations follow NFPA 70E safe work practices and local fire code rules enforced by county and city jurisdictions. Permit renewals and interconnection paperwork are managed for PG&E Rule 21 and SMUD where applicable. Lockout and tagout shutdowns are documented with step by step procedures to ensure safe access during roof work and battery service. Emergency response includes 24/7 phone escalation with target onsite mobilization windows based on service level agreement tiers.

Customized plans, pricing options and engagement

Maintenance plans are tailored by system size, site complexity and customer objectives. Options include time and materials support, fixed price preventative contracts and performance based agreements where payment is tied to availability metrics and production guarantees. Pricing examples for Northern California commercial systems typically range from annual flat fees for small rooftops to per watt per year contracts for larger plants, with add on monitoring and reporting packages.

How customers start service: One Sun performs a site survey and preliminary thermal imaging and IV curve testing within a contracted assessment window. A recommended maintenance schedule, return on investment estimate and a proposed contract are delivered with clear escalation points and SLA metrics.

Case examples and common inquiries

A 500 kW rooftop in Santa Rosa saw a 12% uplift in annual production after an optimized cleaning and inverter firmware update plan. A food processing facility in Sacramento recovered lost capacity by replacing failed string combiners and instituting quarterly inspections. Frequently asked questions address response times, warranty handling, permit coordination with PG&E, and how remote monitoring alerts are prioritized. Contact channels include a dedicated maintenance dispatch line and online scheduling portal for Northern California clients seeking site assessments or to initiate corrective work.