Solar for Home: Complete Guide to Choosing the Right Size of Solar for Your Home

To buy solar for home, check the ratings on the appliances that you use and add up the appliance ratings to get your total load, then send their list and total load to your installer.

In this article, we will guide you on how to get the best, reliable, and sufficient solar for home or solar PV backup for home as your home solar power supply.

Most homes use electricity for TV, interior lighting, phone and laptop charging, fridges, washing machines, and small kitchen appliances. The size of solar PV systems needed for most homes typically ranges from 1.5kW to 3.3kW. Smaller households may operate below 1.5kW, while larger homes may require 5kW, 10kW, or even higher capacities.

How Do I Calculate Solar PV Size for My Home?

This is one of the most common questions homeowners ask. The goal is to determine your total daily energy consumption in watt-hours (Wh).

Step 1: List All Appliances and Their Power Ratings

Every electrical appliance has a label showing its rating in Watts (W) or kilowatts (kW).

1 kW = 1,000 Watts

Write down:

• Appliance name
• Power rating (W)
• Hours used per day

Step 2: Convert Usage Time to Hours

Minutes ÷ 60 = Hours

Example: A 700W blender used for 5 minutes:

5 ÷ 60 = 0.083 hours

If used 3 times per day:

0.083 × 3 = 0.25 hours per day

700W × 0.25 hrs = 175Wh per day

Step 3: Calculate Daily Energy Consumption

Power (W) × Hours Used = Watt-hours (Wh)

Interior Lighting Example:

• 6 bulbs
• 8W each
• 8 hours daily

6 × 8W × 8 hours = 384Wh

Washing Machine:
800W × 1 hour = 800Wh

Example Load for Family: This Family Needs a Solar PV System to Power their Blender, Washer, and Interior Lighting/Bulbs

Appliance	Power (W)	Hours/Day	Daily Consumption (Wh)
Blender	700W	0.25 hrs	175 Wh
6 Bulbs	8W each	8 hrs	384 Wh
Washing Machine	800W	1 hr	800 Wh

Step 4: Add Total Daily Energy

175Wh + 384Wh + 800Wh = 1,359Wh per day

You should send this total to your solar provider, i.e., the company selling you the solar for your home.

This total represents your total daily demand.

A professional solar PV system provider like OneClin Solar Technologies will do the rest of the calculations for you to determine the solar panel sizes and other aspects of the solar PV system that you need. The provider may request to visit your building or site to gauge the space for panel installation and verify your total load.

You may be interested to know how the solar provider knows the number of panels needed for the solar for your home. Let us explain this process here:

How Solar Panel Size is Determined

In Kenya, most areas receive approximately 5–6 peak sun hours per day.

Panel Size (W) = Total Daily Energy (Wh) ÷ Peak Sun Hours

1,359Wh ÷ 6 hours = 227W

Solar systems are not 100% efficient, so installers oversize panels by 30–40%.

227W × 1.4 = 318W

Practical minimum: 350W–400W of panels.

Including Battery Charging

Assume you install a 2.56kWh (2,560Wh) lithium battery.

2,560Wh ÷ 6 peak sun hours = 427W

427W × 1.4 ≈ 600W minimum panel capacity

However, because panels must also power daytime appliances and account for cloudy weather, installers often size higher.

Practical Example:

4 panels × 450W = 1.8kW system

1.8kW × 6 hours = 10.8kWh daily production before losses.

This ensures:

• Full battery charging
• Daytime appliance use
• Reliability during cloudy weather

Why a 3.3kW Solar PV System Suits Most Homes

A 3.3kW solar PV system comfortably powers lighting, TV, fridge, washing machine, phone charging, laptops, and small kitchen appliances. For many average households, it balances affordability and performance without overspending.

It is large enough to power daytime loads while charging batteries for evening use. With proper installation and maintenance, the system can last over 20 years.

Do I Need a Small or Large Solar PV System?

800W – 1.5kW: Suitable for lighting, TV, phone charging, and small appliances.

3.3kW – 5kW: Ideal for medium homes running fridges, washing machines, microwaves, and moderate simultaneous loads.

6kVA – 8kVA inverters: Suitable for higher simultaneous appliance usage.

Solar inverters operate at a power factor of about 0.8:

1 kVA ≈ 0.8 kW
1 kW ≈ 1.25 kVA

Example: A 5kVA inverter ≈ 4kW usable power.

10kW – 20kW systems: Suitable for large homes with air conditioners, pumps, and heavy usage.

30kW+ systems: Ideal for mansions, farms, schools, or commercial buildings.

Where to Get the Right Solar for Home in Kenya

OneClin Solar Technologies is a trusted company selling and installing solar PV systems for homes across Kenya and Africa. The company is run by qualified engineers and technicians who survey sites and provide professional system sizing advice.

Location: Visit us at Venus Complex, Along Northern Bypass, Nairobi.
Calls and Whatsapp: 0724044962
Emails: oneclinsolar@gmail.com