How to choose an Inverter for Solar Power

In today’s world many people around the world are investing in alternative energy source systems. With the advances in technology solar electricity has become poplar. With better technology come lower prices. Perhaps the simplest fact we know about solar power is that it comes from the sun.

The next fact is that it is classified as renewal energy in contrast to fossil fuels (such as coal, natural gas and oil) which are non-renewable. Renewable energy sources are those that are not finite and will not run out in the future. It is the most used renewable energy at the present and the probability of it being widely utilized in the future is likely.

How an Inverter works.

Photovoltaic is an adjective that pertains to the generation of voltage when light energy falls on the boundary between two dissimilar materials, as in two different semiconductors.  The photovoltaic (PV) cells in the solar electric panels convert the suns’ rays into direct Current (DC).

Most appliances anywhere in the world run from alternating current (AC). The usual delivery of direct current by PV modules is 12 volts (V), while most household appliances run at 230 volts (it varies depending on which continent or country you are in).

Here the power inverter comes into the scene. Solar power inverters are very critical components of the solar energy system. The solar inverter changes the electricity into Alternating Current (AC) where it is used to power household needs. You can actually choose from the conventional string inverter or microinverters.

Solar Panels with Sky Background

If the house is not attached to the power grid, the DC power can go into batteries where it is stored until needed. When the current leaves the battery it goes to the inverter where it is changed to Alternating Current (AC).

The electricity then goes into the house to be used as power. There are two main types that you can choose from as far as the quality of the electrical current: pure sine and modified sine. Pure sine inverters will offer the same, constant, high quality electricity like you would get from plugging your device in at home. The power inverters with pure sine technology are going to have a much higher price tag than the modified sine inverters.

Pure Sine vs Modified Sine inverter

One of the biggest questions we get asked in dealing with off-grid energy supply is with the sine inverter. Most people assume they already have one in their RV since they can plug different appliances and accessories into the wall receptacle and use them normally. The first question I ask is, are you plugged into shore power? Or, are you running a generator for this to be accomplished? That’s when things start to get confusing for the consumer and hopefully by the end of this article, you will have a better understanding of how it all works, and the difference in the types of inverters that are available.

An inverters definition is the ability to take electrical power as direct current (DC) and convert that power to alternating current (AC) changing the output voltage and frequency with appropriate transformers and control circuits. Most of the DC current we need for an input power to operate the inverter, comes in the way of 12V or 24V like in our car battery.

The inverter takes this low voltage input and with the help of transistors and amplifiers it can effectively produce a square wave of AC power. Now this square wave has a very high harmonic content with a peak-to-RMS voltage ratio of 1. Some electronic loads are sensitive to this peak voltage, while resistive loads such as those like incandescent lamps respond to the RMS value of the wave, hence the square wave is unsuitable for general use.

A ‘Modified Sine Wave’ waveform will produce a square wave but spends equal time on either side of the frequency sequence cycling four times per cycle at the peaks and zero crossings of the grid while being as easy to generate as a square wave. The biggest advantage to the Mod Sine wave is that it has the same peak-to-RMS voltage ratio as a true sine wave or Pure Sine wave.

They are compatible with most electrical loads except those sensitive to the harmonic content, example: laser printers, fluorescent lighting, audio equipment, variable speed tools and certain clocks. Because this power is not as clean as true sine, the cost is generally much cheaper, but you may get feedback in the sound of buzzing or loss of efficiency as much as 20% and the appliance may run hotter causing the risk of meltdown in the motor.

With less than 3% total harmonic distortion, a true sine or ‘Pure Sine’ wave inverter produces a nearly perfect sine wave output which matches that of your utility-supplied grid power. Thus it is compatible with all AC electronic devices but will cost you as much as 4x the amount compared to the Mod Sine.

Choosing a Power Inverter for Your Home Use

Buying a new power inverter will not only give you more freedom and abilities while you’re on the road, but it can also provide you with emergency preparedness at home. But there are a variety of different manufacturers and models available when you set out to buy one, so it’s important to take a look at a few of the things that really matter in an inverter. Knowing about the basic capabilities as well as the special features that it can provide to you is the best way to ensure that you get the perfect one for your needs.

Start by checking to see if the power inverter you’re looking at features a surge for starting appliances or tools. Most of the best ones will include the ability to create a 200% surge in power for at least a few seconds to facilitate the extra power needed to do so. And take the time to look at what kind of appliances or tools you’ll be running off the  inverter. If there’s a very small gap between the total wattage needed, such as a watt requirement , remember that power surges could push it over the limit.

As we had mentioned before Sine waves are another issue to keep in mind as well when buying a an inverter. Sine waves deliver the most constant type of output possible and some sensitive equipment can’t be used without a power inverter that features them. This feature may cost a bit extra, but is well worth it if you’ll be needed the consistent waves that it delivers. Also take the time to find a new power inverter that boasts short circuit and overload protection so that you’ll know your investment is protected from these issues.

The number of outlets included on a power inverter of any size is an important factor as well, but remember that the total combined wattage needs for all of the items you plug into it must fall below the wattage limit selected. Other features include remote control capabilities and monitors that allow you to view the charge running through the system. These are the basic things you’ll want to look at whenever you set out to purchase a new power inverter. If you keep them in mind when comparing your options you’ll be sure to make a purchase that you won’t regret. 

 Other functions consist of remote control abilities as well as displays where you can see the charge running with the program. These are the basic issues you will want to examine if you attempted to purchase a fresh power inverter. If you have them in your mind comparing your alternatives you will be guaranteed to make a purchase that you will never regret.

An inverter can also be convenient on the go. You can use an Inverter to charge your devices like laptops and Phone right from your RV, boat, car, or truck. In order to determine how powerful you need to go, multiply the amps of the electronics or appliances that your using by 120 to determine their wattage. For example, a laptop with an amp rating of 1.5 will require an inverter of at least 180 watts or more. You can find the amp rating on the device or in its packaging or paperwork.

When planning the solar electricity project for your home, many begin by using solar power for a few of their needs and implement solar power use step-by-step. By taking this approach they are able to put in a larger solar power inverter when their budget allows them to add to what they already are using.