Answers before estimates.
The Hans Energy Systems Learning Center walks San Diego County homeowners through the decisions behind HVAC, solar, batteries, and EV charging — troubleshooting first, honest comparisons second, and what things cost, with no pitch until you ask for one.
Troubleshooting
Diagnose common HVAC, solar, and electrical problems before you call.
Why Does My EV Charger Keep Tripping the Breaker? What San Diego Homeowners Should Know
An EV charger that trips its breaker points to one of five causes: an undersized or shared circuit, a loose connection, heat, a GFCI conflict, or a failing charger. In older San Diego homes with 100-amp panels, the circuit — not the charger — is usually the problem.
Read the guideWhy Is My AC Blowing Warm Air? A San Diego Troubleshooting Checklist
An AC that runs but blows warm air usually has one of six causes: a thermostat setting, a dirty filter, a tripped breaker, a frozen coil, a failing capacitor, or a refrigerant leak. Here is the safe checking order for San Diego homeowners — and the point where DIY must stop.
Read the guideWhy Is My Solar System Producing Less Power? 7 Causes San Diego Homeowners Can Check
Most sudden solar production drops in San Diego County come from one of seven causes — dust and coastal grime, shading, a tripped breaker, an inverter fault, monitoring gaps, panel damage, or normal seasonal dips. Here is how to check each one safely before calling for solar panel repair.
Read the guideMaintenance & How-It-Works
Maintenance checklists and plain-English explanations of how home energy systems work.
How Does NEM 3.0 Net Billing Work for San Diego Solar Owners?
Under NEM 3.0 net billing, SDG&E pays you the avoided-cost rate for exported solar — a fraction of the retail rate you pay to import. That one change reshapes system design in San Diego: self-consumption and batteries now drive the economics instead of raw export.
Read the guideThe San Diego HVAC Maintenance Checklist: What to Do Each Season (and What to Leave to a Pro)
San Diego HVAC systems need a spring cooling tune-up, a fall heating check, and monthly filter attention during fire season. This seasonal checklist splits the work into what homeowners can safely do and what requires a NATE-certified technician.
Read the guideHow Does Home Battery Backup Work During a San Diego Power Outage?
A home battery detects a grid outage and switches your essential circuits to stored power in a fraction of a second — and if you have solar, the panels keep recharging it the next morning. Here is how the transfer works, what a battery can realistically run, and why plain grid-tied solar shuts off in a blackout.
Read the guideComparisons
Side-by-side comparisons to help you choose the right system, brand, or approach.
Level 1 vs. Level 2 EV Charging at Home: What San Diego Drivers Actually Need
Level 1 adds 3–5 miles of range per hour from a standard outlet; Level 2 adds 20–40. For most San Diego commutes Level 2 is the difference between managing charge and never thinking about it — and it unlocks charging during cheap or solar-powered hours. The comparison table settles it.
Read the guideTesla Powerwall vs. Enphase IQ Battery: Which Fits a San Diego Home?
Powerwall 3 favors whole-home backup and high solar input through one integrated unit; Enphase IQ batteries favor modular sizing and pair naturally with Enphase microinverter systems. The right answer usually falls out of three questions about your home — here is the side-by-side.
Read the guideHeat Pump vs. AC + Furnace: Which Is Right for a San Diego Home?
San Diego's mild winters are close to ideal heat-pump territory: one machine replaces both the AC and the furnace, runs at 300–400% effective efficiency, and never needs a gas flue. Here is the honest side-by-side — including the cases where keeping gas still wins.
Read the guideAC Repair vs. Replacement in San Diego: How to Decide Without Wasting Money
Repair usually wins when the system is under 10 years old and the fix is electrical; replacement usually wins past 12–15 years, for compressor or refrigerant-circuit failures, or when the old system runs phased-out R-410A or R-22. Use the $5,000 rule and this comparison table to decide.
Read the guideCost Guides
What clean-energy and HVAC projects actually cost San Diego County homeowners.
How Much Does AC Replacement Cost in San Diego?
A full AC replacement in San Diego typically lands between $8,000 and $16,000 installed — higher with duct replacement or a panel upgrade, lower for a straightforward condenser-and-coil swap. Here is where the money goes, what Title 24 adds, and the questions that keep a quote honest.
Read the guideHow Much Does Solar Panel Installation Cost in San Diego County?
Typical San Diego County rooftop solar runs in the $2.50–$4.00 per watt installed range — roughly $15,000–$28,000 for a 6–8 kW system before incentives, more with a battery. What moves the number: system size, roof complexity, panel and inverter tier, panel-upgrade needs, and storage.
Read the guideRebates & Incentives
Financing, rebate, and incentive guidance for San Diego County energy upgrades.
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