With electricity tariffs on the rise and Malaysia’s push towards renewable energy, many homeowners are exploring solar photovoltaic (PV) systems as a way to cut electricity bills and reduce carbon footprints. However, one common question arises: How do you choose the right solar PV system size for your home?

Selecting the right system size is crucial, too small, and you won’t see the full benefit; too large, and you might overspend on unnecessary capacity. Here’s a step-by-step guide tailored to Malaysian homeowners.

1. Understand Your Energy Consumption

Start by reviewing your Tenaga Nasional Berhad (TNB) electricity bills for the past 12 months. Look for your average monthly kWh usage — this will be the baseline for determining the system size.

• Example: If your household uses 900 kWh per month, your daily consumption is about 30 kWh.

Tip: Consider seasonal changes. Air-conditioning usage in hotter months can significantly increase your consumption.

2. Consider Your Solar Potential

Malaysia’s tropical climate offers 4–5 peak sun hours daily on average. However, shading, roof orientation, and roof angle will affect the actual output.

• North–south facing roofs with a tilt of around 10–15 degrees are generally optimal in Malaysia.

• Avoid installing panels where trees or nearby buildings cast shade during peak sunlight hours.

3. Match System Size to Your Needs

A common rule of thumb in Malaysia: 1 kWp of solar PV generates about 4–5 kWh per day.
Using our earlier example:

• Daily consumption: 30 kWh

• Required system size: 30 ÷ 4.5 ≈ 6.6 kWp

If you aim for 100% offset, a 6–7 kWp system would be suitable. However, you may choose a smaller system (e.g., 4–5 kWp) if budget is a concern, or if you plan to expand later.

4. Factor in New Government Policies and Programs

Malaysia’s Net Energy Metering (NEM 3.0) scheme officially ended on 30 June 2025, meaning new applications are no longer accepted. For new solar adopters, the current approach is Self-Consumption (SelCo), where all generated electricity is used on-site and excess energy is not exported for credit.

If you spend most of the day away from home and use more electricity at night, you may need to consider battery storage or load-shifting strategies to maximise your solar usage.

Always stay updated with announcements from the Sustainable Energy Development Authority (SEDA) or the Ministry of Energy, as new programs or incentives may be introduced in the future.

5. Think About Future Needs

If you plan to add new electrical loads such as electric vehicle (EV) chargers, extra air conditioners, or a home office, size your system with these future demands in mind. Expanding later is possible, but it can be more costly than installing the right size upfront.

6. Budget & ROI Considerations

While larger systems produce more energy, the return on investment (ROI) depends on your consumption, TNB tariffs, and the cost of the installation. A reputable solar provider can prepare a detailed ROI calculation for you, factoring in:

• System cost

• Monthly savings

• Payback period (typically 4–6 years in Malaysia)

• Warranty and maintenance

7. Work with a Certified  and Trusted Solar Installer (Like Us)

Choosing the right system size isn’t just about numbers, it’s also about design, safety, and compliance. Always engage a SEDA-registered solar PV service provider who can:

• Analyse your energy usage

• Conduct a site survey

• Provide a customised system design

• Handle all NEM application processes

8. Final Thoughts

The right solar PV system size for your Malaysian home depends on your electricity usage, available roof space, budget, and long-term plans. With the right planning and professional advice, you can enjoy maximum savings, a shorter payback period, and a sustainable energy future.

9. Thinking about going solar?

Solar Sunyield Sdn Bhd offers free site assessments and customised solar proposals for Malaysian homeowners. Contact us today to find out the perfect solar PV size for your home.