How many solar panels do you need for a heat pump? 2026

1. The core: heat pump consumes kWh, solar panels supply kWh

A heat pump “makes” heat by using electricity to move heat from outside air/ground. Efficiency is expressed in SCOP (average annual efficiency).

• SCOP 3 → 1 kWh of electricity provides ~3 kWh of heat
• SCOP 4 → 1 kWh of electricity provides ~4 kWh of heat
• SCOP 5 → 1 kWh of electricity provides ~5 kWh of heat

In practice, this means: the lower your supply temperature (underfloor heating / low-temperature system) and the better your insulation, the higher the efficiency.

2. Step 1: determine your extra power consumption due to the heat pump

Your total household electricity (lights, cooking, appliances) is already there. A heat pump adds to that. So for solar panels, you usually calculate:

Extra kWh per year = heat pump power consumption + (possibly) heat pump boiler/electric auxiliary heating

Reference values for heat pump power consumption per year

Please note: these are reference values. The actual consumption heavily depends on insulation, hot water use, emission system type, and settings.

3. Step 2: how many kWh does one solar panel produce per year in the Netherlands?

The output per panel depends on watt-peak (Wp), roof orientation (south/east/west), tilt angle, shade, and inverter.

As a simple, useful rule of thumb (NL):

• 1 panel of 400 Wp often yields roughly 320 – 380 kWh per year
• South (good) = higher, east/west = slightly lower but often more stable throughout the day

For quick calculations, we use a practical average in this guide: 350 kWh per panel per year (400 Wp).

4. Step 3: solar panel calculation formula for heat pump

Number of solar panels ≈ (extra heat pump consumption in kWh per year) ÷ (kWh output per panel per year)

Example with 350 kWh output per panel:

• Heat pump consumption 3,500 kWh/year → 3,500 ÷ 350 = 10 panels
• Heat pump consumption 5,000 kWh/year → 5,000 ÷ 350 = 15 panels

This is the “theoretical” calculation to generate as much electricity annually as your heat pump consumes. However, generation and consumption do not always coincide. Therefore, it is wise to also consider self-consumption.

5. Most important reality: self-consumption (you don't use everything directly)

Solar panels produce the most during the day and in summer. A heat pump, on the other hand, consumes relatively much in winter and in the evening. Without smart control or a home battery, you therefore do not directly use all solar power yourself.

What does this mean in practice?

• You can “compensate annually,” but in winter, you still buy electricity
• You feed a portion of your solar power back into the grid (depending on net metering/feed-in tariff)
• With smart control (boiler/EMS), you increase your self-consumption

Practical rules of thumb for self-consumption

• Without smart control: often 25–40% direct self-use
• With smart hot water/boiler charging: often 35–55%
• With home battery + smart EMS: often 55–80% (situation-dependent)

Therefore, in practice, people sometimes install slightly more panels than the simple formula indicates – depending on their goal (maximally self-sufficient vs. purely financial).

6. Calculation examples: how many panels for hybrid vs all-electric?

Example A: Hybrid heat pump (2,000 kWh/year extra)

• 2,000 ÷ 350 ≈ 6 panels

In practice, many households with hybrid heat pumps install 6–10 extra panels, depending on roof space and future plans (EV, induction cooking).

Example B: All-electric heat pump in a terraced house (3,500 kWh/year)

• 3,500 ÷ 350 ≈ 10 panels

Example C: All-electric heat pump in a detached house (6,000 kWh/year)

• 6,000 ÷ 350 ≈ 17 panels

Note: if you also start cooking electrically, own an EV, or are a work-from-home family, the required output increases.

7. Additional factors that change the number of solar panels

1) Roof orientation and shade

East/west is fine, but the output per panel can be lower. Shade can make a significant difference. This affects your “kWh per panel.”

2) Heat pump settings

• Too high supply temperature → lower efficiency → more power
• Smart heating curve → higher efficiency → less power

3) Emission system

• Underfloor heating = usually more efficient
• Radiators can also work, but sometimes with low-temperature radiators or adjustments

4) Hot tap water

Frequent showering or a large family? Then the heat pump consumes more.

5) Future plans

• Electric car (EV)
• Induction cooking
• Home battery

In that case, it is wise to plan panels “in advance.”

8. Smart strategy: panels + heat pump + (optional) boiler/EMS

If your goal is to use as much solar power as possible for your heat pump, these choices help:

• Heat pump + smart control (EMS) → consumption shifts to daytime where possible
• Heat pump boiler / larger buffer tank → heat water during sunny periods
• Home battery → storage of daytime power for evening/night (situation-dependent)

This not only makes your installation cheaper to operate but also more future-proof against changes in feed-in tariffs.

9. 30+ Frequently Asked Questions

1. How many solar panels do I need for a heat pump?

Rule of thumb: (heat pump kWh per year) ÷ (350 kWh per panel) = number of panels. This often works out to 6–18 panels, depending on the house and system.

2. How many panels for a hybrid heat pump?

Usually 6–10 extra panels, as hybrid often uses 1,500–2,500 kWh per year.

3. How many panels for all-electric?

Often 10–18+ panels, depending on house size, insulation, and hot water use.

4. Do I need to cover all my heat pump electricity with solar panels?

No. Financially, it can also be smart to install “enough” to cover a large part and cover the rest via the grid.

5. Does this also work in winter?

In winter, panels produce less. You generate annually, but in winter, you often still buy electricity from the grid.

6. Is east/west worse than south?

Not necessarily. East/west often provides a better spread throughout the day, which can increase self-consumption.

7. Are more panels always better?

Not always. It depends on the feed-in tariff, your own consumption, and future plans.

8. Does a home battery help?

Yes, for higher self-consumption. Financial gain depends on tariffs, consumption, and system costs.

9. Can I control the heat pump with solar power?

Yes, with smart control/EMS, you can, for example, schedule hot water production during the day.

10. What if I have shade on my roof?

Then the output per panel may be lower. Optimizers or micro-inverters can help.

Tip: do you want me to expand this FAQ to 40–60 questions? Say “make FAQ longer” and I will provide an extra block.