If you’ve been thinking about going solar, you’ve probably come across two very different options – Solar PV panels and Solar Thermal panels. Both sit on your roof. Both use energy from the sun. But that’s roughly where the similarities end.
Irish homeowners often get these two confused, and honestly, it’s an easy mistake to make. But choosing the wrong one for your home could mean missing out on serious savings. This guide breaks down exactly what each system does, what it costs, what grants are available, and – most importantly – which one actually makes sense for your home in Ireland.
What Is Solar PV and How Does It Work?
Solar PV stands for Solar Photovoltaic. The panels contain photovoltaic cells that convert sunlight into electricity. That electricity powers your lights, appliances, your kettle – everything that runs off your home’s electrical circuits.
One of the biggest misconceptions about solar in Ireland is that it only works when the sun is shining. In reality, Solar PV panels generate electricity even on cloudy days, pulling around 60% of their energy from indirect sunlight. The remaining 40% comes from direct sun. So our Irish weather – grey as it often is – isn’t the barrier people think it is.
Key things to know about Solar PV:
- Generates electricity for your whole home
- Works on overcast days – no direct sunlight needed
- Lifespan of around 20 years, with no moving parts to wear out
- Surplus electricity can be sold back to the grid (depending on your utility provider)
- Adding battery storage can roughly double your savings
What Is Solar Thermal and How Does It Work?
Solar Thermal is a completely different system. Instead of generating electricity, it heats water directly. Solar collectors (either flat panels or tubes) absorb heat from the sun and use it to warm the water stored in your hot water cylinder.
It doesn’t power your TV or charge your phone – it’s purely focused on your domestic hot water supply. For families with a high hot water demand – busy households with teenagers, or homes where the shower is running constantly – the savings can be significant.
Key things to know about Solar Thermal:
- Heats water only – not electricity generation
- Can cover 60% to 80% of your total hot water needs
- Saves roughly 50% per year on hot water costs
- Works on overcast days, same as Solar PV
- Installation is typically completed within a day
Solar PV vs Solar Thermal: The Main Differences
| Feature | Solar PV | Solar Thermal |
| Output | Electricity | Hot Water |
| Annual Savings | Significant household electricity savings | Up to 50% on hot water bills |
| Hot Water Coverage | Indirect (via immersion diverter) | 60%–80% direct |
| SEAI Grant Available | Yes – see current amounts | Yes – see current amounts |
| System Lifespan | ~20 years | ~20 years |
| Battery Storage Option | Yes | No |
| Grid Export Possible | Yes | No |
SEAI Grants: What Can You Claim in Ireland?
This is where the numbers get interesting. The Irish government, through the Sustainable Energy Authority of Ireland (SEAI), offers grants to help homeowners with the upfront cost of both systems.
- Solar PV: eligible for an SEAI grant
- Solar Thermal: eligible for an SEAI grant
To check your full eligibility and see what grants apply to your home, visit the SEAI grant page on the Green Energy Homes website. The team at Green Energy Homes can walk you through the application process – it’s something they handle regularly for Dublin homeowners.
Which System Is Right for Your Home?
There’s no single right answer here. It really depends on what you’re trying to achieve.
Choose Solar PV if:
- You want to reduce your overall electricity bills
- You’re interested in selling surplus electricity back to the grid
- You’d like the option to add battery storage down the line
- You’re thinking about getting an EV charger and want to power it with solar energy
- You want a system with the widest range of household benefits
Choose Solar Thermal if:
- Your biggest running cost is hot water
- You have a large family with high daily hot water demand
- You already have a good cylinder-based hot water system and want to cut those costs specifically
- Your electricity usage is already fairly low and you don’t need to generate power
Can You Have Both?
Yes, and some homeowners do go down this route. If your budget and roof space allow, combining Solar PV and Solar Thermal gives you the best of both worlds – free electricity and heavily subsidised hot water. That said, for most Dublin homes, Solar PV is the more versatile choice simply because the electricity savings touch every part of the home.
Does Solar Work in the Irish Climate?
This is the question every homeowner asks first, and the answer is a firm yes. Both Solar PV and Solar Thermal are designed to work in climates exactly like Ireland’s. As mentioned, 60% of the energy they capture comes from diffuse, indirect sunlight – the kind we get plenty of here, even in January.
Neither system requires blazing sunshine to deliver real savings. What they do need is a south-facing roof with minimal shading, a reasonably clear line to the sky, and a properly sized system for your household’s needs.
Planning Permission: What You Need to Know?
For most domestic installations, planning permission is not required for either Solar PV or Solar Thermal panels – as long as the total panel area doesn’t exceed 12m². This covers the vast majority of standard home installations.
If your system is larger than that, planning permission will be needed. Green Energy Homes can assist your architect with sketches and scale drawings if required. They’ve completed many installations across Dublin without any planning issues.
Why Choose Green Energy Homes?
Green Energy Homes is a Dublin-based renewable energy company that installs both Solar PV and Solar Thermal systems for homeowners across the city and beyond. Before any installation goes ahead, they carry out a full technical and safety survey of your property to make sure the system is sized and positioned correctly.
The process is straightforward:
- Provide your Eircode (or GPS coordinates)
- Get a price confirmed
- Pre-installation survey completed
- System installed – usually within a single day
They also handle the paperwork around SEAI grants, taking that task off your plate entirely.
You can visit the team at their showroom:
Swords Showroom: Unit F2, Swords Enterprise Park, Drinan, Swords, Co. Dublin, K67 WF72.
Or give them a call on 016855575 to talk through which solar option suits your home.
Conclusion
Both Solar PV and Solar Thermal are solid investments for Irish homeowners – and both are backed by SEAI grants that make the upfront cost far more manageable. The key is matching the right system to your home’s actual needs.
If you want to cut electricity bills across the board and have the flexibility to grow your system with battery storage or an EV charger, Solar PV is the stronger choice for most homes. If your main concern is a sky-high hot water bill and you have a large household, Solar Thermal does that job very efficiently.
Still unsure? The team at Green Energy Homes can assess your home and tell you exactly which system – or which combination – would give you the best return. Call 016855575 or visit the Swords showroom to get started.
FAQs
1. What is the difference between Solar PV and Solar Thermal?
Solar PV converts sunlight into electricity for your home. Solar Thermal uses the sun’s heat to warm your domestic hot water supply. They serve completely different purposes.
2. Do solar panels work in Ireland’s cloudy weather?
Yes. Both Solar PV and Solar Thermal systems get around 60% of their energy from indirect sunlight, so they work well even on overcast Irish days.
3. What SEAI grants are available for solar panels in Ireland?
Both Solar PV and Solar Thermal are eligible for SEAI grants. Check current figures and full eligibility details at the SEAI grant page.
4. Can I sell excess electricity back to the grid with Solar PV?
Yes, depending on your utility provider, you can export surplus electricity to the grid and receive a payment for it.
5. Does Solar Thermal heat my home as well as my water?
No. Solar Thermal only heats your domestic hot water. If you want to reduce space heating costs, you’d need to look at options like an air source heat pump instead.
6. How much can I save with Solar Thermal?
Solar Thermal can cover 60%–80% of your total hot water needs and save around 50% on your annual hot water costs.
7. Do I need planning permission for solar panels in Ireland?
Not in most cases. Planning permission is only required if your total panel area exceeds 12m². Standard home installations usually fall well below this.
8. How long does installation take?
Both systems are typically installed within a single day, with most of the work carried out externally on your roof.
9. Can I install both Solar PV and Solar Thermal on the same roof?
Yes, if your roof space and budget allow, you can run both systems together for electricity generation and hot water savings simultaneously.
10. How do I get started with Green Energy Homes?
Simply provide your Eircode to get a price confirmed. Green Energy Homes will then arrange a technical survey and schedule your installation. Call 016855575 or visit greenenergyhomes.ie to get in touch.