Solar PV vs solar thermal: what is the difference?
Solar PV (photovoltaic) panels generate electricity, while solar thermal panels heat water for your taps and heating. Most UK homes choose solar PV because the electricity can power anything, can be stored in a battery, and can be exported for payment. Solar thermal only offsets hot water and is now less common for new installs.
How they compare
| Feature | Solar PV | Solar thermal |
|---|---|---|
| Produces | Electricity | Hot water |
| Powers | Anything in the home | Hot water only |
| Storage | Battery | Hot water cylinder |
| Export income | Yes (SEG) | No |
| Typical use today | Most common | Niche |
Which should you choose?
For most homeowners, solar PV is the more flexible and valuable choice, especially when paired with an electric immersion diverter that sends surplus PV electricity to heat your hot water. This gives you the benefit of solar thermal without a separate system. SunSum's calculator estimates a PV system, which is what the vast majority of UK installers fit.
Frequently asked questions
- Can solar PV heat my water?
- Yes, indirectly. A solar diverter sends surplus PV electricity to your immersion heater, heating water for free instead of exporting at the lower rate.
- Is solar thermal worth it?
- For most homes PV with a diverter is the better all-round investment, though solar thermal can suit homes with very high hot water demand.
Related questions
Indicative estimates based on UK average data. Last updated 27 May 2026.