A genuine off-grid solar system in Ireland is technically possible but financially brutal for most homes. The SEAI Solar Electricity Grant does not apply to off-grid installations. You earn nothing from the Clean Export Guarantee because there is no grid connection to export to. The battery bank required to survive an Irish winter, when solar output can drop to a fraction of what the panels produce in June, adds tens of thousands of euro before you have bought a single panel. For a remote rural site where the grid connection cost alone runs to €20,000 or more, it can still be the right call. For almost everyone else, a grid-tied system with a home battery delivers most of the independence at a fraction of the cost.
- The SEAI Solar Electricity Grant (max €1,800 in 2026) requires an ESB Networks connection. Off-grid systems are not eligible
- Off-grid systems earn zero CEG export income. Grid-tied homes currently earn 15.89c–32c per kWh exported
- Irish winter solar output is very low. A battery bank sized for a full week of backup in December is the main cost driver
- 0% VAT applies to solar PV supply and installation on private residences in Ireland, grid-tied or off-grid
- Off-grid makes most sense where the grid connection cost is prohibitive, typically rural sites far from the nearest ESB pole
What Off-Grid Solar Actually Means
An off-grid solar system has no connection to the ESB electricity distribution network. The panels generate electricity, a battery bank stores it, and every watt your home uses must come from that system. Run the battery flat during a cloudy week in January and your options narrow quickly: diesel generator or no power.
Off-grid solar works in places like southern Spain or Portugal, where winter sun is plentiful and runs of low-generation days are short. Ireland sits at 51–55 degrees north. The same 4 kWp system that generates upward of 500 kWh in a good June can drop to under 150 kWh in December. A run of grey Atlantic days with heavy cloud cover can mean almost nothing from the panels for several days straight.
None of this is an argument against solar in Ireland generally. On a grid-tied system, a low-generation spell just means you draw from the grid. The grid is always there. Off-grid, your battery does that job, and it has to be large enough to carry you through the worst stretch the Irish winter can manage.
The SEAI Grant Does Not Apply to Off-Grid Systems
The SEAI Solar Electricity Grant (up to €1,800 in 2026) is one of the main reasons Irish solar installations make financial sense. It comes with a specific requirement that shuts off-grid installations out entirely.
To qualify, you must apply to ESB Networks to be connected to the electricity distribution system. Your SEAI-registered installer handles that network connection application. An off-grid system has no grid connection. There is nothing to apply for, so there is no grant.
In practice, a grid-tied 4 kWp installation costing €8,000 leaves you paying around €6,200 after the grant. The same panel array on an off-grid system costs €8,000 with no offset, and you still have to add the battery bank, a charge controller, and an off-grid inverter on top of that. Off-grid inverters are a different, typically more expensive category than grid-tied hybrid inverters.
The 0% VAT rate on solar PV supply and installation still applies. That is the only concession you keep.
The Winter Problem: Why Battery Sizing Is So Expensive
The battery bank in an off-grid system has two jobs. Getting through each night is the easy one. Getting through extended low-generation stretches in winter is where the costs become serious.
Ireland's average household uses around 4,200 kWh a year, according to the Commission for Regulation of Utilities, which works out at roughly 11–12 kWh per day. A 4 kWp solar system generates around 800–900 kWh per kWp per year, so roughly 3,600 kWh annually. Spread evenly, that is about 10 kWh a day. Solar yield is not spread evenly.
Generation peaks from April through August. December and January are the worst months by some distance, as covered in our guide to solar panel performance in Ireland. Those are the months when the gap between what the panels produce and what your household needs is at its widest.
Off-grid engineers typically size the battery bank to carry a home for five to seven days with no meaningful generation, so a grey January week does not leave you without power. At 11–12 kWh daily consumption and a target of five days autonomy, you need 55–60 kWh of usable battery capacity.
Lithium iron phosphate (LFP) batteries, the current standard for home storage in Ireland, are typically rated at 80–90% usable depth of discharge. To reach 55 kWh usable, you need around 65–70 kWh of rated bank capacity.
A 10 kWh home battery costs €4,500–€7,000 installed in Ireland. Scaling up to a 65 kWh off-grid bank puts the batteries alone at €30,000–€45,000, before panels, inverters, or installation. That is not a misprint. Off-grid battery sizing is a different exercise entirely from fitting a single 10 kWh battery to a grid-tied home.
No Clean Export Guarantee Income
Grid-tied solar owners in Ireland earn money every time they export surplus electricity to the network. Under the Clean Export Guarantee (CEG), suppliers currently pay between 15.89c and 32c per kWh exported, depending on your provider. A well-sized 4 kWp system on a typical Irish home exports somewhere between 1,200 and 1,800 kWh a year, which adds up to a few hundred euro annually.
Off-grid systems earn nothing from exports. There is nowhere to send surplus. In summer, when the panels are generating far more than you need, that energy goes to waste or into an immersion heater via a hot water diverter. Over a 20–25 year panel lifespan, the cumulative value of lost export income is real money.
For the full export rates by supplier, see our Clean Export Guarantee guide.
When Off-Grid Solar Actually Makes Sense in Ireland
There is one scenario where the off-grid numbers work: when connecting to the grid costs more than the off-grid system itself.
ESB Networks charges for extending the distribution network to unconnected rural properties. When a house is far from the nearest pole, those connection costs can reach €15,000, €20,000, or more. At that point, the comparison changes. You are not choosing between €6,200 for a grid-tied system and €60,000 for off-grid. You are comparing €26,200 all-in for grid-tied against an off-grid system that avoids the connection bill entirely.
Other situations where off-grid is a genuine fit:
- Remote agricultural buildings or cabins with very low energy demands. A small panel array and a modest battery bank can power lights and a pump without needing a network connection
- Holiday homes or glamping pods used seasonally in spring and summer. The winter problem largely disappears when the building is empty in December
- Properties with a backup generator already in place. The off-grid battery only needs to bridge a few days, with the generator covering longer cloudy stretches
For a full-time family home on a normal rural site with a standard grid connection available, off-grid solar is rarely the right answer.
The Alternative: Grid-Tied with a Battery
Most people asking about off-grid are really asking how to get closer to energy independence without paying an extraordinary amount for it. For almost every Irish home, the answer is a grid-tied system with a home battery.
The setup works like this: your panels generate during the day, the battery stores the midday surplus, and you draw on stored solar in the evening. When the battery is depleted, you draw from the grid. When the sun is generating faster than you can use or store it, you export and earn CEG income. You are never without power whatever the weather does, and you are not paying for 65 kWh of battery capacity to survive an Irish January.
A 4 kWp system with a 10 kWh battery currently costs around €10,000–€15,000 installed in Ireland after the €1,800 SEAI grant. That is typically a quarter to a third of what a properly sized off-grid system would cost. The full costs and payback maths are in our solar panels with battery guide.
If storm outages are the concern, many modern hybrid inverter and battery systems can run certain circuits on stored solar during a grid outage. You get meaningful backup protection without the cost and complexity of a full off-grid design.
What an Off-Grid System Actually Costs
Off-grid system costs vary widely by property size, energy demand, and how many days of autonomy the design targets. There is no standard price list in the way there is for a 4 kWp grid-tied installation. The main cost components are:
- Solar panels: the same panels as a grid-tied system, typically €5,000–€12,000 for the array and racking, excluding battery and inverter
- Battery bank: the biggest variable. A small off-grid cabin might manage with 15–20 kWh; a full-time Irish family home typically needs 50 kWh or more. Budget €4,500–€7,000 per 10 kWh module
- Off-grid inverter and charge controller: these manage the battery bank and regulate power without a grid reference signal. They are a different, typically more expensive category than grid-tied hybrid inverters
- Installation and commissioning: more involved than a standard grid-tied job
- No SEAI grant: no €1,800 offset on any of the above
A full off-grid system designed for a standard Irish family home, with five days of winter autonomy and a correctly sized panel array, is likely to start around €40,000–€60,000 all-in. Some remote rural projects run higher. Get a specialist quote before committing; the right system depends on factors that need a proper site survey to assess.
Frequently Asked Questions
Can I get the SEAI solar grant for an off-grid system?
No. The SEAI Solar Electricity Grant requires you to apply to ESB Networks to be connected to the electricity distribution system. An off-grid installation has no grid connection, so this condition cannot be met. The grant is not available for off-grid systems. (Source: Citizens Information, grants for solar panels, last edited 10 March 2026.)
Does 0% VAT apply to off-grid solar installations?
The 0% VAT rate applies to the supply and installation of solar PV panels on private residences and schools in Ireland, introduced in May 2023. This rate applies to the solar panels themselves and their installation regardless of whether the system is grid-tied or off-grid. Confirm the VAT treatment for associated equipment such as off-grid inverters and battery banks with your installer.
How many batteries do I need for an off-grid solar system in Ireland?
It depends on your daily energy consumption and how many days of autonomy you want to design for. An average Irish household uses around 11–12 kWh a day. To cover five days without meaningful solar generation, you need roughly 55–60 kWh of usable storage, which translates to around 65–70 kWh of rated battery capacity (accounting for depth-of-discharge limits). That is six to seven 10 kWh battery modules. The right number for your home depends on your actual consumption and site conditions.
What happens to surplus solar electricity in an off-grid system?
Once the battery is full, excess generation from the panels has nowhere useful to go. Most off-grid installations include a hot water diverter, which redirects surplus electricity into an immersion heater rather than letting it go to waste. Beyond the immersion, you cannot export to the grid and you cannot earn Clean Export Guarantee income.
Is off-grid solar worth it for an Irish home?
For most homes with a standard grid connection available, no. The absence of the SEAI grant, the loss of CEG export income, and the cost of a battery bank large enough for an Irish winter typically push the total system cost to two to four times that of a grid-tied equivalent. Where an off-grid system makes financial sense is when the cost of connecting to the grid is itself very high, typically rural sites far from the nearest network connection, or seasonal-use properties where the winter problem is reduced by low occupancy.
Can a grid-tied battery system provide backup during a power cut?
Many modern hybrid inverter and battery systems sold in Ireland include an "islanding" or backup mode that keeps certain circuits running during a grid outage. This is not the same as a full off-grid system, but it provides meaningful protection against short-term outages from storms. Ask your installer specifically about backup capability if this matters to you.
Grant conditions and figures from Citizens Information (grants for solar panels, last edited 10 March 2026). Battery costs from market data current as of mid-2026. System cost estimates are indicative ranges for planning purposes; get a specialist survey for your site before committing.