Solar panels allow you to consume electricity without the burden of leaving behind carbon footprints. However, even with better efficiencies and performances available nowadays, you may not always be able to power your home with solar panels alone.
To use the electricity your solar panel produces, you may need additional appliances. One such appliance is an inverter. However, with varied specifications, you may not know what to look for when buying an inverter for your solar panels. Thus, it would help if you went through all the details before deciding.
What Size Inverter For 200W Solar Panel?
When you select the size of an inverter for your solar panel, its rating must be similar to that of the solar panel. So for an inverter that is grid-tie, you should ensure that it is 200W. On the other hand, if the inverter is going to be off-grid to store energy, you must use one that is smaller than or between 500W and 600W.
How To Calculate The Size Of Inverter For Your Solar Panel?
Choosing the right sized inverter is essential. If your array is too oversized for your inverter, it will produce more power than it can tackle. So, your inverter will cut off some power coming to it and convert the rest into AC.
It means that you will not be able to utilize all the power that your panels are generating. Generally speaking, the size of your inverter should be slightly smaller or larger than your solar panel.
So, it mainly depends on the rating of your solar array. The ratio between the array and the size of your inverter is usually between 1 and 1.5. These upper and lower limits, and most inverters, fall around 1.25.
Do You Need An Inverter For Your Solar Panel?
Before answering this question, you need to know what inverters do precisely. You must have heard repeatedly that inverters are an essential piece of equipment for your solar panel. But why is it so important?
It is because solar panels generate electricity in DC. It is a direct current, and this is not the form of electric current that you would use as electricity in your home. This is because direct current supplies electricity at a constant voltage. Thus, it can be dangerous to you.
The type of electricity you use in your home for various applications is AC. It is an oscillating type of current. So, unless you are directly connecting solar panels to DC appliances, you need an inverter.
The inverter converts the energy that your solar panel produces into AC. It does so by quickly changing the direction of the flow of DC. Hence, it changes the DC into AC. This is the basic principle. However, other devices, such as filters, are used to achieve the same.
Which Type Of Solar Inverter Should You Use?
The size of the inverter you use is extremely important. It will directly impact the losses of power and the optimization of the performance of your solar panels. But the type of solar inverter you use is also just as important. The following are the various kinds of solar inverters you can think of:
This is used when solar panels are employed on a large scale. However, it can also be used for mid-sized projects. As the name suggests, when you use this type of inverter, every solar panel is connected to the inverter.
If you have several solar panels and are looking for something budget-friendly, the string inverter is the one for you. This type of inverter connects an entire string of panels to one inverter. However, you should be careful when using this one.
As the string panels are connected to the string inverter, it is susceptible to power losses. If any part of the string, that is, any particular panel on the string, cannot produce power, it will affect the whole string. So, when you use this type of inverter, you should be careful about shade, even if it is partial.
If you have issues with shade or, for some reason, you cannot ensure that an entire string gets the right amount of sunlight, you can think of using microinverters. These connect to every solar panel. Hence, it solves the problem of shade.
In this way, you can almost always get the optimum output from your solar panels. However, these advantages come at a price. Microinverters generally tend to be more costly than other types.
How Are On-Grid Inverters Different From Off-Grid Ones?
On-Grid inverters do not use a battery bank. These on-grid systems produce energy only when the utility power grid is available, directly transmitted into the utility feed. They are less expensive than other systems since they don’t use batteries.
Though your system will also close down if the utility company’s power goes down, it supports Net metering that helps to decrease electricity payments by more than 80 %. Further, these systems are less costly and easy to install. Internet monitoring is available in these systems.
One of the biggest failures in these systems is that they cannot provide energy during grid outages. On the other hand, off-grid inverters are primarily designed to be used with solar for domestic and commercial purposes.
Moreover, these off-grid systems have complete self-sustaining capacity. So, it is independent of the grid. It is beneficial where there are regular power outages. Off-grid systems don’t need batteries, so there is no need to purchase high-cost batteries like other systems.
Generally, the inverter will have the capacity to shut itself off if the battery voltage falls. Otherwise, it may cause battery damage. Also, it provides backup power that can be used in emergencies like power outages.
I hope you understand how to choose a suitable inverter for your solar panel. In addition to this, you would also know the type of inverter you need to pick. If you face any issues, you can always read more details and make a decision.
Eng. Matthew Joseph Nandirio is the Founder of walkingsolar.
After graduating from the University of Houston in 2002, matt started working as an electrical and electronic engineer for several multi-national solar energy companies.
He has a wide range of experiences including solar system requirement analysis, planning, maintaining, debugging and even solar device development through research.
He now shares his 20 years of expertise through his articles on the walkingsolar website.
Further, he is also the author of two books on Solar Technology, “Solar Power for Villages” and “DIY Solar System for Dummies”.