PV systems are measured by the amount of power in Kilowatts (kW) per day. A 4.5kW system will generate 4500W of energy to power fridges, TVs, Wifi Routers, laptops, lights, and security cameras.
For solar panels that deliver 4.5kW of power, you need an inverter that can convert that energy from DC to AC and have enough storage to supply the appliances that utilize this power level. A 4.5kW system would be sufficient for a smaller home installation.
To understand how much power a 4.5kW system would produce, we need to look at the following :
- How much power is 4.5kW, and what can it run
- How to see whether a 4.5kW system is enough for your home
- How many solar panels would be required to generate 4.5kW
Basic information about your power consumption will tell you whether a 4.5kW system will be worth it for your home.
What Can A 4.5kW Solar Panel System Run?
A 4.5Kw system can power all devices connected as long as the total wattage does not exceed 4500W, including the startup wattages. Before we look at the devices and appliances a 4.5kW system could run, we need to understand how to calculate the load to determine the size of the system required.
Here, we are working with a 4.5kW system, meaning the connected load would be 4500W. In most cases, PV systems are not designed to run electrical water heaters as these typically take up around 2000W-3000W alone, depending on the water heater size and element.
To calculate how many appliances a 4.5kW system could power, you need the wattage of each device you want to connect. Remember that there are running wattages and startup wattages to consider.
The running wattage is the device’s power when running, while the startup is what it uses when it is first switched on.
As a simple example, look at the following(wattages not to scale):
- Laptop – 50W
- Lights – 450W
- TV – 200W
- WIF Router – 100W
- Home theatre – 1200W
- Fridge – 300W / 600W
- Air conditioner – 500W/ 1000W
Total running wattage: 2900W
Total wattage: 3700W
The aircon and fridge have two values because the second one is the startup, which is how much power the appliance uses when it first turns on. Most devices that have a motor will have a startup wattage value.
Based on these appliances, a 4.5kW system is more than enough to cover the power supply, and remember that the actual wattage may be less than those stated.
How Much Power Will A 4.5kW System Generate In A Day?
This system would generate about 80% of its capacity at best, depending on the array’s orientation and the level of solar radiation received. All affect the generational ability of the panels.
At 80%, a 4.5kW solar panel system would deliver around 3600W or 3.6kW of power per day. Under ideal solar conditions and temperature, the system may get close to its rated capacity.
When considering a 4.5kW solar panel system, you need to have a good idea regarding solar exposure and other factors like temperature (lower temperatures mean greater generational efficiency) and shade.
All of the above will affect the system’s ability to generate power, and the peak solar months will yield higher daily averages than during autumn and winter.
Will A 4.5kW System Be Enough For Your Home?
If all the connected devices in your home don’t exceed 4500W, a 4,5kW system will be sufficient. Remember that solar panels are only the generating element of a PV system. You need an inverter and enough battery capacity to power the devices.
To calculate whether a 4.5kW system could power your home, first, you need to finalize all the devices you want the system to power, then add up all the wattages on each appliance, including a startup wattage if applicable.
The wattages are found on the appliance information tag at the back, side, or underneath the device. If you can’t find it, type in the name and model number into Google, and you should see the technical specs online.
If the total wattage does not exceed 4500W, then a 4.5kW solar panel system can deliver. Still, again you need to have an inverter of similar or slightly higher capacity and the battery capacity to power them for as long as you require.
Some folks only want the PV system for power during the day, in which case, you wouldn’t need batteries, but if the weather were cloudy or rainy, your PV system would only deliver a portion of the power required as it is not getting full solar coverage.
How Many Solar Panels Would You Need For A 4.5kW System?
You would require any configuration of solar panels whose total wattage achieved 4500W or close to it, so 9 x 500W panels would be an option.
Things become a little more complex regarding the number of panels needed to generate 4500W. It’s not simply a case of finding enough panels and installing them; you need to consider a few aspects first.
For example, 15 X 300W panels Vs. 9 X 500W panels may be a better option as you get more solar exposure with a larger surface area from the 15 panels than you do from the 9.
Also, the cost per watt on each panel is a definite consideration as you may be paying more for the 500W panels than the 300W panels. Most home installations use boards rated between 280W and 365 W, which are the most cost-efficient.
Your primary concern is the available roof space and whether the roof can handle the additional weight. The lighter panels require more space and exert less weight overall, but you may need the higher wattage panels where there is less available space.
Developments in higher wattage panels from 400W -500W have some suppliers no longer stocking the lower wattage panels, as these are more efficient in generation and cost per watt.
Measurements and roof structure assessments are done before the quantity and wattage of panels are selected and installed. Your contractor should advise you on your roof condition and whether you require some additional structural support for the panels or not.