Solar panels on your farm shed — when do you actually break even?

Every second ad on Farming Independent is solar panels. Every rep at the mart is handing out leaflets. Your neighbour got them last year and says they're great. But when you ask "how long until they pay for themselves?" — nobody gives you a straight answer.

That's because the answer depends on your farm. Your county. Your roof. Your electricity bill. Your grant. And what you do with the surplus power.

This article gives you the real numbers — and shows you how to calculate your own break-even using an AI assistant and five minutes of your time.

What's driving the push

Ireland added over 1GW of solar capacity in 2025. Farm sheds are a big part of that. Large, south-facing roofs with no shade and no planning objections. Installers love them.

Three things make the economics work better than they did five years ago:

1. TAMS III covers up to 60% of the cost of solar PV on qualifying farms, with a maximum grant of €90,000.
2. SEAI's Micro-generation Support Scheme lets you sell surplus electricity back to the grid.
3. Budget 2026 extended the €400 tax-free threshold for income from selling surplus solar power.

That's real money. But it still depends on what you spend, what you generate, and what you use.

What it costs

A typical 20kW system on a farm shed costs €16,000 to €22,000 before grants. After TAMS at 60%, your out-of-pocket drops to roughly €6,500 to €9,000.

Larger systems — 50kW or more for bigger dairy operations — run €35,000 to €55,000 before grants. After TAMS, you're looking at €14,000 to €22,000.

Installation takes two to four days. Most systems connect to your existing meter with minimal disruption.

What you earn back

Your solar panels save you money two ways: reducing what you buy from the grid, and selling what you don't use.

Self-consumption is where the real value sits. Every kilowatt-hour you generate and use yourself saves you whatever you'd pay ESB or your supplier — typically €0.30 to €0.40/kWh at current rates.

Export to grid earns less. Under the SEAI Micro-generation Support Scheme, surplus electricity typically sells at €0.10 to €0.15/kWh. That's a fraction of what you'd save by using it yourself.

Here's the trick most installers don't emphasise: if you charge an EV from your solar instead of exporting, that power is worth €0.40 to €0.50/kWh to you in avoided fuel costs. Using your own power beats selling it every time.

The sunshine question

Ireland isn't Spain. But it's not as bad as people think — and the difference between counties is bigger than most realise.

According to Met Éireann, Dublin and the sunny south-east get around 1,400 to 1,500 sunshine hours per year. Donegal and the north-west get closer to 1,100. That's a 30% gap.

A 20kW system in Wexford will generate roughly 30% more electricity per year than the same system in Donegal. Your break-even shifts by a year or more depending on where you farm.

The Teagasc solar pilot on dairy farms showed approximately 20% lower electricity bills. That's a useful benchmark — but your result will vary based on system size, self-consumption rate, and location.

Typical break-even

After TAMS grant and with reasonable self-consumption, most farm solar systems pay for themselves in five to eight years. The panels themselves last 25 to 30 years. So you're looking at 17 to 25 years of essentially free electricity after break-even.

Here's what moves the needle:

| Factor | Faster break-even | Slower break-even | |--------|-------------------|-------------------| | Location | South-east (Wexford, Waterford) | North-west (Donegal, Mayo) | | Self-consumption | High (dairy, cold storage, EV) | Low (shed mostly empty) | | TAMS grant | 60% approved | Not eligible | | Electricity price | Rising (trend since 2021) | Falling (unlikely near-term) | | System size | Matched to your usage | Oversized for your needs |

How AI gives you a personalised number

This is where a five-minute conversation with an AI assistant saves you a week of waiting for quotes.

Try this prompt:

"I'm a dairy farmer in County Cork with a 30kW solar system quoted at €28,000. I got 60% TAMS approval. My annual electricity bill is €8,500. I use about 70% of my power during daylight hours. Cork gets roughly 1,350 sunshine hours per year. Calculate my annual solar generation, self-consumption savings, export income at €0.12/kWh, and break-even year."

The AI will model it for you. It won't be exact — no model is without your actual half-hourly usage data. But it gives you a solid first estimate.

Follow up with:

"What if electricity prices rise 5% per year? How does that change break-even?"

"What if I add a 22kW EV charger and use 4,000kWh per year for charging?"

"Show me the difference between Cork and Roscommon for the same system."

This isn't a substitute for a proper installer quote or a Teagasc energy audit. But it stops you going in blind.

What to watch out for

Oversizing. A system that generates far more than you use means you're exporting at €0.12/kWh instead of saving at €0.35/kWh. Match the system to your actual daytime usage.

Installer claims. Some quote break-even based on 100% self-consumption. That's unrealistic for most farms. Ask what they assume for export percentage.

Planning. Systems under 50kW on agricultural buildings are generally exempt from planning permission. Above that, check with your local authority.

Grid connection. Systems over 6kW need ESB Networks approval for grid export. Your installer handles this, but it can add weeks to the timeline.

Official advice: TAMS grant rates, SEAI export tariffs, and tax-free thresholds change. Always confirm current figures with your Teagasc advisor, SEAI (seai.ie), or on gov.ie before signing contracts.

Where to get help

• Teagasc: Book a farm energy audit. They'll assess your roof, usage, and grant eligibility. See teagasc.ie/rural-economy/farm-management/farm-energy.
• SEAI: Full details on the Micro-generation Support Scheme at seai.ie.
• TAMS III: Check eligible items and current rates at gov.ie.
• Met Éireann: Check your county's sunshine hours at met.ie.

The bottom line

Solar panels on a farm shed are a solid investment — if you size the system right and use the power yourself. After TAMS, break-even is five to eight years. After that, the electricity is free for two decades. Get the TAMS approval first. Then get three installer quotes. And run your own numbers with an AI assistant before you sign anything.

Part of our Farm Energy series. Read next: Electric tractors — where are we really? An honest review for Irish farms