Solar inverters are crucial components of any solar system. An off-grid solar inverter is the heart of an off-grid solar system as it manages energy conversion.
Solar energy is like a raw material. The solar panels of such systems absorb this undiluted energy and generate DC electricity. However, a standard home runs off AC electricity. Hence, DC won’t suffice. That’s where off-grid solar inverters come in.
These inverters convert the DC electricity from the solar panels into AC to run any home. Off-grid solar inverters provide an alternate source of electricity that can cut down electricity bills by a large margin.
Read on to find out about the solar inverter market and its investment potential.
Overview of the solar inverter market
In 2021, experts valued the global solar inverter market at US $9.31 billion. According to reports, they expect it to expand at a 6.2% compound annual growth rate (CAGR) from 2022 to 2030.
Since the economic decline of gas prices in 2014, other alternative energy sources have taken the spotlight. Coupled with the increasing energy demand, which is driving the need for renewable energy, the solar inverter market has never been more promising.
In 2021, the utility segment led the solar inverter market with a 44.0% revenue share. The reduced cost of solar equipment and power, rising government subsidies, and higher demand for renewable energy are factors responsible for this market’s growth potential.
What are the types of solar inverters to buy in 2022?
Pure sine waveform inverters
Pure sine wave inverters are excellent at reproducing high-efficiency electricity, similar to what consumers can get from the grid. They can power all devices in a home that use AC and other devices like radios that can suffer reduced performance from interference.
Since these inverters use high-end electronic components to produce reliable and clean electricity, they can get expensive. They can cost two times more than regular inverters.
Nevertheless, pure sine wave inverters will keep equipment protected, helping to increase their total lifespan. They are also highly efficient and will save energy for consumers by up to 90%.
Pure sine wave inverters work with more sensitive equipment like television sets, refrigerators, variable speed motors, microwaves, and medical equipment.
That’s not all. Some pure sine waveform inverters can handle heavy-duty applications. They are powerful enough to offer a complete power generation system for commercial establishments that power everything from lights to lifts and escalators. These inverters can also run the most expensive, sophisticated, and sensitive office equipment without pollution risks.
Modified sine waveform inverters
Modified sine waveform inverters are less efficient than their pure sine wave counterparts. They present a cost-effective way for consumers on a tight budget to enjoy the benefits of solar power.
However, the electricity from these inverters is nothing compared to what consumers can get from the grid. At best, they can run typical resistive loads like lights and some appliances.
Although modified sine wave inverters produce imperfect replicas of AC power, they are suitable for many mobile power applications. But, they can’t handle sensitive components. Why? The AC power produced by modified sine wave inverters is choppy. Their polarity switches abruptly from positive to negative, which has adverse effects on more delicate, sensitive equipment.
Consumers with medical equipment that needs backup power, like CPAP machines, won’t use a modified sine wave inverter. Most devices connected to these inverters will produce a humming sound and may overheat.
Notwithstanding, modified sine waveform inverters are cost-effective and appeal to consumers that don’t care about the efficiency of their appliances.
Consumers can also use these inverters to run simple systems that don’t have sensitive electronics. Other devices that can work include old tube televisions, phone chargers, and water pumps.
Appliances like compressors with AC motors, refrigerators, and microwaves will run, but won’t offer efficient performance.
Off-grid solar inverters: factors to consider before buying them
Off-grid solar inverters are an absolute necessity for solar systems. However, it’s important to make considerations before rushing into any decision. Here are eight factors retailers should consider before buying off-grid solar inverters.
Load power factor
Load power factor is a measurement of the average power ratio to the R.M.S current and voltage product. Sine wave inverters have a load power factor ranging from 0.7 to 0.9 with a 0.9 rated value. If these inverters have a fixed load power, they will also have a low power factor, which will increase the required capacity.
However, increased capacity will also lead to higher costs. It will also increase the apparent power and loop current of the solar system. Unfortunately, this increase will reduce the solar system’s efficiency and escalate energy loss.
Output voltage waveform distortion
All sine wave inverters have a specified maximum allowed harmonic content (or waveform distortion). Generally, they express it according to the total output voltage waveform distortion, which must not go beyond 5% and 10% for single-phase output.
The waveform distortion output of these sine wave inverters produces eddy current and other losses on inductive load. Hence, any excessive waveform distortion will result in overheated components. Such situations can damage electrical equipment and impact the system’s operational efficiency.
For this reason, buying pure sine wave inverters would be a better investment because they offer less waveform distortion of output voltage.
Solar inverter efficiency
The ratio of input power to output power (expressed in percentages) under specified working conditions is a solar inverter’s efficiency. Usually, a solar inverter’s efficiency refers to how efficient it is under 80% of pure resistance load.
Due to how expensive solar systems are, most solar inverter brands try to maximize the efficiency of their products. Recently, mainstream inverters have a nominal efficiency between 80% and 95%. The efficiency of most low-power inverters is nothing less than 85%.
Output voltage stability
Solar systems have storage batteries that help store electric current generated by the solar panels before the inverter converts it to usable electricity. However, the charge and discharge of these batteries heavily influence output voltage stability.
Solar systems can have different batteries with various output voltages. For instance, if a battery has a 12V nominal value, its output value can vary between 10.8V and 14.4V. Anything more than this range would damage the batteries.
Any solar inverter for such batteries must not have more than a 5% rated value for its steady-state output voltage. If there’s a load change, the output deviation must not exceed 10% of the rated value. Otherwise, the solar system won’t be effective.
Solar inverters deal with pure electricity, so they must have safety or protective features. Abnormal situations can occur anytime and damage an inverter without protective measures. Here are some safety features retailers need to watch out for before purchasing:
- Over-current protection
Inverters with over-current protection will avoid damage in the event of a short-circuit or the current exceeding the value threshold.
- Overheat protection
Solar inverters should have this safety feature to prevent damage from overheating.
- Input over-voltage protection
This function will protect the solar inverter when the input voltage exceeds 130%.
- Input under-voltage protection
This measure will protect the solar inverter if the input voltage goes below 85% of the rated voltage.
- Output short-circuit protection
An inverter’s short-circuit protection duration should not exceed 0.5 seconds.
- Lighting protection
Another important safety feature inverters must have is protection against lightning strikes.
- Input converse-connection protection
Solar inverters should have this function for protection against inversely connected negative and positive poles.
Inverters have various components that can produce a lot of noise. However, solar inverters must not exceed 80 dB noise level for normal operations. Small-scale inverters should also stay within the 65 dB noise limit.
Rated output capacity
Rated output capacity deals with the solar inverter’s rated output current and voltage. Most solar inverters show their rated output capacity in kVA or VA units. It also refers to the amount of power a solar inverter can supply continuously.
An inverter’s rated output capacity must be a minimum of 25% more than the required total power for running all appliances simultaneously. Otherwise, it will only power appliances within its capacity.
Frequency of rated output
Good inverters should have a stable rated output frequency. The acceptable value is 50 Hz, and should only deviate less than 1% of the original value under working conditions.
Loads like refrigerators and washing machines (with motors) would need this stable frequency value. If the value fluctuates, it will result in low efficiency and overheating.
Renewable energy is the new trend, and solar energy is leading the industry. More consumers are looking for alternatives to reduce electricity costs or are disconnecting from the grid completely.
Solar inverters are crucial for photovoltaic systems. Consumers looking for high-efficiency electricity would love the pure sine wave inverter. Modified sine wave inverters will suffice for those looking to power a few lights and appliances.
Retailers must leverage the huge potential of the off-grid solar inverter market to generate greater profits.