Solar PV converts sunlight into electricity for power, while solar heating uses sunlight to directly heat water or air for residential and commercial use.
Solar energy offers two main technologies for homes: photovoltaic (PV) panels for electricity and thermal systems for heating. While both harness sunlight, they serve different purposes with unique advantages. This guide breaks down their differences to help you choose the right solution.
How Solar PV and Solar Heating Work
Solar Photovoltaic (PV) Systems
PV panels convert sunlight directly into electricity using semiconductor materials like silicon. When sunlight hits the panels, electrons are released, creating direct current (DC) electricity. An inverter then converts this to alternating current (AC) for home use.
Solar Thermal Systems
Solar heating captures the sun’s heat through collectors, typically tubes filled with glycol or water. This heated fluid transfers warmth to a water tank, providing hot water or space heating. Unlike PV, thermal systems don’t generate electricity.
Key Differences Between Solar PV and Solar Heating
| Feature | Solar PV | Solar Heating |
|---|---|---|
| Energy Output | Electricity | Heat (hot water/space heating) |
| Efficiency | 15-22% | 70-90% |
| Applications | Power all home appliances | Primarily water heating |
| Storage | Batteries required | Hot water tanks store heat |
Cost and Maintenance Comparison
Installation Costs
Solar PV systems typically cost more upfront than thermal systems. However, PV prices have dropped over 70% in the last decade. Thermal systems remain cheaper for water heating alone.
Maintenance Requirements
PV systems need minimal maintenance – occasional cleaning and inspections. Thermal systems require more care due to moving parts and fluid circulation. Expect annual maintenance costs around £200 for thermal systems.
Lifespan
Quality PV panels last 25-40 years with gradual efficiency loss. Thermal systems typically last 15-20 years before needing component replacements.
Which Is Right For Your Home?
When Solar PV Makes Sense
- You want to power multiple appliances
- Electric vehicle charging is a priority
- You prefer low-maintenance solutions
- Long-term investment is important
For whole-home energy solutions, consider pairing PV with decorative electric heaters that complement your interior.
When Solar Heating Shines
- Your main goal is reducing water heating costs
- You have high hot water demand
- Space heating is a priority in colder climates
- You want maximum energy efficiency
For pool owners, solar pool heaters can extend swimming seasons efficiently.
Advanced Options and Hybrid Systems
PV Diverters
These devices channel excess solar electricity to heat water, combining benefits of both systems. They maximize self-consumption of solar energy.
Seasonal Performance
PV works year-round, though output drops in winter. Thermal systems face greater seasonal variation but can integrate with existing heating systems.
Environmental Impact
Both technologies reduce carbon footprints significantly. PV offsets grid electricity, while thermal reduces fossil fuel use for heating. According to U.S. Department of Energy, a typical solar water heater can prevent 4,000 pounds of CO2 emissions annually.
For those in extremely cold climates, supplementing with indoor propane heaters can provide backup warmth during low-sun periods.
