Ground Source Heat Pump in Ireland — Borehole Cost, When It's Worth the Premium

Ground source heat pump (GSHP) in Ireland: €18,000–€30,000 installed. Borehole €4,000–€8,000 (100–150 m deep). SEAI grant €6,500. Net cost: €11,500–€23,500. More expensive than air-to-water but more efficient (COP 4–5 vs 3–4 for air-to-water) and quieter. Worth it for large houses (200+ m²) with a big garden (1+ acre for the borehole). Not worth it for a standard 150 m² house. The borehole takes 1–3 days to drill; the heat pump takes 2–3 days to install. SEAI grant is conditional on a BER assessment after the work.

TL;DR

• Ground source heat pump (GSHP) in Ireland: €18,000–€30,000 installed. Borehole €4,000–€8,000. SEAI grant €6,500.

• Net cost: €11,500–€23,500. More expensive than air-to-water but more efficient and quieter.

• Worth it for large houses (200+ m²) with a big garden (1+ acre for the borehole). Not worth it for a standard 150 m² house.

When this matters most

You're considering a ground source heat pump.

When this doesn't apply

You've already specified an air-to-water heat pump.

Frequently asked questions

How much does a ground source heat pump cost in Ireland?

€18,000–€30,000 installed. Plus €4,000–€8,000 for the borehole. SEAI grant €6,500. Net €11,500–€23,500.

Is a ground source heat pump worth it in Ireland?

For large houses (200+ m²) with a big garden (1+ acre for the borehole), yes. For a standard 150 m² house, no — air-to-water is cheaper and good enough.

How deep is a borehole for a heat pump in Ireland?

100–150 m typical. Depends on the geology. Limestone is good (high thermal conductivity). Clay is poor (low thermal conductivity). Drilling takes 1–3 days.

Sources

SEAI, Heat Pump Grants 2026. https://www.seai.ie/grants/