Electricity has become an integral part of our daily lives. We rely on electricity from lighting to electronic devices for almost everything. When a power failure occurs, all work and plans are disrupted.
The solution to this problem is to choose the right size inverter for your home. A home inverter converts direct current (such as electricity from batteries or solar panels) into alternating current to power household appliances.
But what size inverter do I need? Worry no more, this article covers the basics of inverters and how to choose the right size inverter for a home!
What is an inverter？
An inverter does not generate electricity but converts incoming DC power into AC power. This conversion usually involves converting the DC power into a waveform, such as a sine wave or modified sine wave, that matches the desired AC power characteristics.
Which is the better inverter for home use?
📍Modified sine wave inverters for home
There is a big difference in how these two inverters get priced. Modified sine wave inverters are less expensive, but may not be as good as pure sine wave inverters in terms of output waveform quality and efficiency. The choice between a pure sine wave inverter and a modified sine wave inverter depends on the equipment you want to use and how sensitive it is.
For example, if you use a modified sine wave inverter with sensitive equipment such as laptops, stereos, projectors, etc., these audio devices will produce hum. However, it works well for general household appliances such as lights and kettles. You can use a modified sine wave inverter on simple systems without sophisticated electronics or even audio equipment. Note, however, that it may not work with devices such as electronic watches and battery chargers.
Also, while some appliances may seem to run fine, you may find that they get hotter and run slower than usual. This can be bad as it can shorten the life of the device.
📍Pure sine wave inverter (best inverter for home)
A pure sine wave inverter is a type of power inverter that produces a near-perfect sine wave output, which is often the preferred choice for many modern electronic products. Pure sine wave inverters tend to be more expensive, but they perform better than modified sine wave inverters and are suitable for a wide range of household appliances and equipment, providing a stable, high-quality power supply.
Devices that require pure sine wave inverters include electronic equipment with AC motors (refrigerators, microwaves, and compressors), audio equipment, medical equipment, and video equipment.
Pure sine wave inverters are the best inverters for a home.
Read More: Modified vs Pure Sine Wave Inverter: What is the Difference
Calculate the total wattage of appliances in your home
The first step in sizing your home variation is to calculate the total power of the appliances you want to run in your home. To do this, you need to make a list of all your appliances, including refrigerators, air conditioners, microwaves, washing machines, televisions, computers, etc., and determine their respective power ratings. These ratings are usually found on the appliance's packaging or in the manual. Add them up to get the total wattage.
Then calculate the required wattage as accurately as possible. This is because an inverter that is too small will not provide enough power, and one that is too large will be a waste of money and may not be necessary for your home's electrical needs.
Surge power
The start-up power of some appliances (e.g. refrigerators and air conditioners) is usually higher than the power consumed by the appliance during normal operation. This is because, at the moment of start-up, the appliance requires extra power to start working. Surge power is usually transient and of short duration, but can cause instantaneous stress on the electrical system. In particular, appliances with electric motors require much more surge power to start than to run.
So if your equipment has surge power, you must also calculate the total surge power value. Make sure that the inverter can cope with the extra load demand when the device starts up.
For a simple estimate, add the power ratings of the required equipment and then add 20-25% to the total power. This allowance will ensure that your inverter can cope with unexpected peaks in power demand. The final estimate will give you a rough guide to the total power requirements of your home, allowing you to select the right inverter to effectively manage your energy needs.
Inverter efficiency
The conversion efficiency of an inverter is the energy conversion efficiency it can achieve when converting DC power to AC power. It is also important to consider the efficiency of the inverter. Typically, solar inverters can have a conversion efficiency of between 85% and 96%. A high-efficiency inverter will convert input power into usable output power more efficiently, meaning that it will use less input power to produce the same output power as an inverter with a lower efficiency.
Calculate the number of batteries you need
When choosing an inverter for your home, it is important to consider the number of batteries required. Especially if you plan to use the inverter to continue to power your appliances in the event of a power outage. Deep-cycle batteries are commonly used in inverter systems and can be a significant cost factor. The size of the inverter you choose will determine the number and size of batteries required to power the load. Make sure that the batteries can support the power output of the inverter.
By choosing an inverter that is only capable of powering basic equipment, you can minimize the number of batteries required and reduce the overall cost. This design ensures that the battery system only needs to support the most critical equipment. In addition, running all the appliances puts more stress on the inverters, which can lead to a loss of system efficiency and shorten the life of the batteries. Selecting inverter-powered appliances can therefore effectively reduce the load on the system, extend battery life, and improve overall performance.
It is more cost-effective to use inverters to power essential appliances during power outages and non-essential appliances when the grid is available. In this way, you can optimize the performance of your inverters to ensure that they provide stable power to essential equipment at critical times while extending their life and reducing maintenance costs.
To calculate the number of batteries you need, you first need to work out how many hours of standby power you need. Battery capacity is measured in ampere-hours (Ah).
Divide your total daily watt-hour requirement by the voltage of the battery. If your daily energy requirement is 3000 watt-hours and you have a 24V battery system, you will need 150Ah (2400 Wh/24V = 100Ah).
It is also important to consider the depth of discharge of the battery. For lead-acid batteries, a depth of discharge of 50% is usually recommended, while the standard depth of discharge range for lithium-ion batteries is 80%.
What size inverter will you need?
Choosing the right size inverter is critical to meeting your home's energy needs. The capacity of the inverter should match the total power demand you have calculated for your home's appliances, plus an extra buffer to handle peak loads and potential increases in energy demand. If an inverter is too small, it won't be able to meet the energy needs of all your appliances, especially if they are used at the same time. On the other hand, an inverter that is too large is inefficient, resulting in unnecessary energy consumption and higher costs.
If you are planning to install solar panels, you need to consider the capacity of your solar system. The inverter's size should match the solar system's capacity to convert solar energy into usable AC power efficiently. If you need to expand your solar system in the future, choosing an inverter with some expansion capability will make the job easier.
FAQs
What size inverter do I need to run a house?
The size of the inverter will depend on the appliances you need to power. Calculate the total wattage of all the appliances that will be powered at the same time. Add a safety margin of 20-25% to the total wattage to allow for surge power. For most homes, a 3000 to 5000-watt inverter is usually sufficient.
Is it worth buying an inverter for your home?
If you want uninterrupted power during a blackout or to install solar panels to save money on your electricity bill, an inverter is a must. An inverter converts direct current (from batteries or solar panels) into alternating current for use by appliances in your home.
Can you run a refrigerator on an inverter?
Most domestic refrigerators are typically between 100 and 800 watts, and refrigerators usually require additional power to start up high-power equipment such as compressors. Typically, the surge power of a refrigerator is about two to three times its rated operating power. Typically, a 2000-watt inverter will run a refrigerator without any problems.
Will a 3000-watt inverter run my house?
If your home's power needs revolve around basic household appliances such as fridges, televisions, lamps, computers, etc., these appliances will typically be in the 3000-watt range in total. A 3000-watt inverter is sufficient for the daily operation of these appliances. If you are considering expanding your solar system in the future, you should consult a professional to ensure you have the right size inverter for your needs.
