How AskSolar checks a quote

For a new system of panels, with or without a battery, after the SEAI grant, with value kit (a Solis, GoodWe or similar inverter, and a Dyness or similar battery):

€2,500 + €500 per kWp + €250 per kWh of battery

For example, 6.3 kWp with a 10 kWh battery: €2,500 + €500 × 6.3 + €250 × 10 = €8,150.

At 6 kWp with a 10 kWh battery the rule gives €8,000, the same as the common rule of thumb of €1,000 per kWp plus €200 per kWh. The €2,500 base is there because the inverter, scaffolding, labour and paperwork cost about the same on a small roof as on a big one. So small systems come out higher than €1,000 per kWp, and large systems without a battery come out lower (about €2,500 lower at 10 kWp).

The check prints this sum on every result, so you can follow it and redo it yourself.

The 2026 grant is €700 per kWp for the first 2 kWp, then €200 per kWp from 2 to 4 kWp, up to €1,800. A system of 4 kWp or more gets the full €1,800.

1 kWp

€700

2 kWp

€1,400

2.5 kWp

€1,500

3 kWp

€1,600

4 kWp

€1,800

6 kWp

€1,800

The check asks how your price was given:

• After the grant: we compare your price as it is.
• Before the grant: we take the grant for your system size off first, and show the sum.
• No grant (a new build, or the grant already claimed): we add €1,800 back to the rule, because the rule assumes the grant.

The rule assumes the full €1,800 grant. A smaller system gets less (for example 2.5 kWp gets €1,500), so the rule adds the difference back: €300 in that case.

The 2027 grant level is expected to be lower than 2026, but nothing is confirmed until Budget 2027 on 6 October 2026. A €600 battery grant is expected in Budget 2027 on 6 October 2026. It is not confirmed, and the rules and start date are not published. We will update the grant figures, and date the change below, after the Budget.

Tick any of these that are in your quote, and the rule adds a fixed allowance for each:

• EV charger (+€1,000)
• Ground-mount frame (+€2,500)
• Hot-water diverter (+€600)
• Changeover switch (+€500)

The changeover switch allowance is for a manual switch that lets a few circuits run from the battery in a power cut. An automatic whole-house backup unit costs more, and the rule does not cover it.

Each result compares your price with the rule for your exact spec, extras and grant basis.

• KeenMore than 15% under the rule

  Could be a good deal, or something is left out. Check what's missing before you pay a deposit.

• Good5% to 15% under

  A good price for the spec. Still check what's included.

• About the going rateFrom 5% under to 20% over

  About what this spec usually costs. The band reaches further over than under because premium all-in-one systems usually cost more than value kit for the same size. More than 10% over, the result says so: fair for premium all-in-one kit, on the dear side for value kit.

• On the dear side20% to 35% over

  More than the spec usually costs. Ask what's behind the price.

• Too dearMore than 35% over

  Well over what the spec usually costs. Get more quotes.

The percentage printed with a result always sits inside that result’s range, so a quote a fraction over 20% reads as 21%, not 20%.

A price under 60% of the rule for its spec gets no result. This is measured on the money for the system itself, after taking out any extras you ticked. A figure that low is more likely a deposit, a monthly payment or part of the price, so the check asks you to look at the price again. None of the 17 public quotes the rule is checked against comes close: the lowest is 87% of its rule.

From 60% to 70% of the rule, you see the result, but the check makes no card, link or text to share for it, because a price that low is unusual.

Every result turns the money back into a system at the rule, after taking out any extras you ticked. It counts panels of 450 W and prices a 10 kWh battery (or your own battery, if it is bigger). It stops at 18 panels (about 8.1 kWp), or at your own system’s size if that is bigger, because that is about what a typical house roof and a standard single-phase connection take. Money beyond that is shown as money over the rule for that system, not as more panels.

Every result lists a few questions chosen for your spec: are the brands named, is the deposit 25% or less, is the grant and connection paperwork included, are bird mesh and scaffolding (or, for a ground mount, the frame and trench) included, and is the quote valid for a while. A big battery, a keen price or a dear one adds questions.

We checked the rule against 17 quotes posted publicly in 2026 where the replies gave a clear verdict on the price. The rule agrees with 16 of the 17, and it never points the other way: it never calls a quote keen or good where the replies called it dear, or dear where they called it fair.

How we count agreement: a reply of “keen” agrees with Keen or Good; “good value” with Keen, Good or About the going rate; “fair” or “on par” with Good or About the going rate; and “dear” with On the dear side or Too dear. Two of the 16 are “good value” replies the rule reads as about the going rate. Counted strictly, it agrees with 14 of the 17.

The one it misses is a large system with no battery and premium kit, which replies called expensive. The rule reads it as about the going rate.

These 17 quotes are part of the rule’s test suite, so any change to the rule is checked against them before it goes live.

• It is a rough guide, not a valuation. It can’t see your roof, the cable runs or the quality of the kit.
• It doesn’t know brands. Premium panels or a premium battery can put a fair quote above the rule, and a cheap quote can leave things out.
• It doesn’t price a battery on its own, or one added to panels you already have. That is priced differently: there is no SEAI solar grant for it, and it is not zero-rated for VAT. A price can’t show that a quote is an add-on, so the check asks whether the panels are new, and gives a plain note instead of a result when they aren’t.

Inspired by the free solar quote analysers Irish homeowners have shared with each other for years.

It starts from the €1,000 per kWp plus €200 per kWh rule of thumb and corrects it for small systems, large systems without a battery, extras and the tiered grant.

Free for homeowners. AskSolar may charge an installer a flat fee if you ask us for an introduction and you accept it. Every quote is checked against the same published rule, and no installer can pay to change a verdict. The price check never sends your details to an installer.

• v1, 28 Sep 2026: first published rule.

Think the rule gets a quote wrong? Email hello@asksolar.ie with the numbers (no names needed). Corrections are dated and listed here.