How large a solar panel system should I choose?

Finding the perfect solar panel system is about matching it to your life and your needs. Whether you live in a small apartment or a large house with an electric car, EcoRay helps you hit the mark using AI and global data. Our advanced solar panels deliver 30% more electricity than standard estimates, so they make the most of Denmark's weather. Here's a quick guide to choosing the right size, spiced up with examples and a clear diagram.

What affects the size?

Your electricity consumption is the most important factor – the more electricity you use, the larger a system makes sense. The roof's location also plays a role; a south-facing roof with a good slope catches the most sun, while shade from trees or neighbors can slow down production. A battery allows you to store surplus electricity for later, so you save more. If you have a heat pump or an electric car, a larger system quickly becomes a good investment.

Examples of systems for different homes

Here are three examples of system sizes adapted to typical Danish households, with production figures adjusted up by 30% for our high-performance panels: Small home (apartment or small house) Electricity consumption: 2,000–3,000 kWh/year (e.g., a couple without large appliances). Recommended system: 3 kWp. Production: 3,250–4,290 kWh/year. What it means: With a battery, you use 60–75% yourself (1,950–3,218 kWh), which covers most of your needs. The rest (1,032–1,340 kWh) can be sold for DKK 1.00–1.50/kWh, yielding DKK 1,032–2,010/year. You save up to 70% on your electricity bill (approx. DKK 2,800–4,200/year at DKK 2/kWh). Why it fits: A compact solution for small households that want to save without a large investment. Family house (with heat pump) Electricity consumption: 6,000–8,000 kWh/year (e.g., family with a heat pump). Recommended system: 7 kWp. Production: 5,687–7,508 kWh/year. What it means: With a battery, you use 60–75% yourself (3,412–5,631 kWh), which covers much of the heat pump's electricity. The surplus (1,806–2,345 kWh) is sold for DKK 1,806–3,518/year. You save 60–70% on your electricity bill (approx. DKK 8,400–11,200/year). Why it fits: Perfect for families who want to lower heating costs. Large home (electric car and heat pump) Electricity consumption: 10,000–12,000 kWh/year (e.g., family with an electric car and heat pump). Recommended system: 10 kWp. Production: 11,700–14,300 kWh/year. What it means: With a battery, you use 60–75% yourself (7,020–10,725 kWh), which covers the electric car and heat pump. The surplus (3,575–6,110 kWh) is sold for DKK 3,575–9,165/year. You save up to 70% on your electricity bill (approx. DKK 14,000–16,800/year). Why it fits: Ideal for homes with high consumption that want to drive and heat almost for free.

Why EcoRay?

We make it easy to find the right solar panel system: Our analyses map your electricity consumption and roof conditions to find the perfect size. We design the system and battery to suit you, whether you have an electric car, heat pump, or lower consumption. We offer competitive prices for maximum value. Our partners and installers handle the installation, while we manage the process. With EcoRay behind you, you get a reliable partner all the way. A battery and grid balancing boost your self-sufficiency and income, especially if you use a lot of electricity.

Get started with EcoRay

A solar panel system of the right size can save you thousands of kroner and make you less dependent on the electricity grid. Visit our website and try our smart calculator to get a tailor-made offer that shows what you can save and earn. Contact us for a non-binding chat, and get started with solar panels – with EcoRay as your wingman.