Solar panels are a great way to produce green energy, save money and reduce your carbon footprint, but it’s important that you know everything you can about solar panels and how they work, including solar panel output, before you invest in a new solar panel system.
If you’re looking at getting solar panels installed on your home, you’re likely wondering exactly how much energy different types of solar panels produce, and how much solar panel output you need. Here’s the breakdown with tips from Panelit Solar.
How do you know how much electricity a solar panel will produce?
Solar panels will be marketed with a wattage attached to them. This wattage is the solar panel output, measured in a unit called watts (W). The higher the wattage of your solar panels, the more electricity generated (in comparison to a lower wattage solar panel in the same conditions).
An average solar panel in the UK, for example, at 350 W, will produce an average solar panel output of 265 kilowatt hours (kWh) of electricity each year. If your solar panel system has 6 of these, then your household solar panel output would be 1590 kWh per year.
The exact amount of electricity produced by your solar panels will depend on the conditions. These are things like the angle of your roof, the shade, the temperature, the direction of your roof and the weather. It will also depend on how much usable sunlight your solar panels are subjected to. You can use an average as an estimate, but be aware your solar panel system may not reach the average solar panel output.
What is the average solar panel output per day?
In the UK, a 350 W solar panel is considered average. On average, these solar panels produce 0.72 kWh of electricity per day. Most houses will have more than 10 of these, though, so you can multiply 0.72 by 10 (or how many solar panels you have) for a rough estimate of around 72kWh per day.
Calculating the solar panel output
Solar panels work best in peak sunlight. To calculate a more accurate solar panel output, you need to take that into consideration. You can do this by multiplying the solar panel wattage by the number of sun hours in the day. For example:
- a 350 W solar panel on a property in the south of England that experiences 5 hours of sunlight each day = 350 x 5 = 1750
- You can then take that figure and multiply it by how many solar panels you have installed. So for an average three bed house, the solar panel output will be somewhere around 1750 x 12 = 21,000 kWh of electricity
This can still vary depending on weather, cleanliness, etc. But it is closer than the general wattage of a solar panel.
How important is the solar panel system output?
It is important to consider the output of your solar panels, as you should aim to match your energy usage when installing solar panels. Usually, a solar panel installer will be able to calculate the necessary solar panel output and match you up with the right solar panels for your solar panel system.
However, it is also important to note that unless you install a solar panel system with battery storage, you will likely only use around 50% of the energy produced by your solar panels. This is because solar panels provide energy in real-time, and often people are not home during the day when energy production is at its highest, and solar panels do not produce electricity during the night when it is dark.
Installing a battery for electricity storage is a great way to increase the amount of renewable energy usage your home has. You will be able to use around 80% of the energy that your solar panel produces with a battery in place. This makes a solar PV system much more cost-efficient, and can also help to increase energy independence.
What affects how much electricity solar panels produce?
As mentioned above, knowing how many hours of sunlight your solar panels will get and how many you can fit on your roof will help to estimate how much electricity your solar panels can produce and help to determine whether solar power is a good option for you.
There are, though, things that can still change how much energy your solar panels will be able to produce, and many of these things are unavoidable. Some factors that will change how much energy your solar panels produce are:
The season
In the UK, our winters are much darker on average. This means that our solar panel systems are given much less direct sunlight, reducing the power output. On average, solar panels make 50% less electricity in the winter, meaning how much energy you use from the grid in the winter months will increase. This power output decrease is pretty much impossible to avoid.
The type of solar panel
Different solar panels produce different amounts of energy. There are two main types of solar panels:
- monocrystalline panels
- polycrystalline solar panels
Monocrystalline panels have a higher solar panel efficiency, and generally work better in higher temperatures and shady conditions. They are great for solar panel systems in hotter countries, and are the most efficient way to get renewable energy into your home.
Polycrystalline panels, on the other hand, have a lower solar panel efficiency and are less efficient at the higher temperatures. In the UK, this is not a particularly big problem.
Due to their differences in how much energy they produce due to their efficiency, monocrystalline solar panels are more expensive. There are, however, various solar panels on the market with higher efficiencies that aren’t too pricey.
The direction of your roof
North facing roofs will generally produce less energy, regardless of what type of solar panel is used, purely because the solar panel is unlikely to get any direct sunlight.
Birds and dirt
Dirty solar panels will have a lower power output. Things like dust, grit, leaves and bird droppings can all impact the power output, and impact how much solar power you have access to which is why companies also add costs for pigeon proofing.
Picking solar panels to make the most of their power output
To find the best solar panels for your solar system, you should consult a professional. They will be able to determine how efficient your solar panels need to be, how many panels you need, and what angle etc. to put them in for your house to benefit the most from them.