In photovoltaic (PV) and energy storage systems, the inverter serves as the core hub for energy conversion and a key device determining the system's power generation efficiency, stability, and safety. Many users face a common confusion when selecting a model: the price of different types of inverters on the market ranges from a few cents to nearly two yuan per watt, and the price difference for products with the same power can even reach several times. What exactly causes this price difference? Faced with a variety of product types, which one is most suitable for your scenario? This article will dissect the root causes of price differences and provide precise selection suggestions based on different application scenarios, helping you avoid selection pitfalls and choose an inverter that achieves "both cost-effectiveness and practicality."
I. Core Reasons for Price Differences Between Different Types of Inverters
The pricing of an inverter is not solely determined by the brand, but by a combination of multiple factors such as technical route, structural design, core components, and functional configuration. Among these, four core dimensions directly widen the price gap and are the key to distinguishing the value of different types of inverters. Ordinary users can focus on these points to quickly understand the price logic.
(I) Technical Route and Structural Complexity: Core Gap in Basic Costs
Different types of inverters have drastically different working principles and structural designs, which directly determine their basic production costs and are the root cause of price differences. Currently, the mainstream inverters on the market are mainly divided into four categories: central inverters, string inverters, microinverters, and energy storage bidirectional inverters (PCS). Their structural complexity and cost gradient are clearly visible, corresponding to the needs of different application scenarios.
1. Central Inverter: First Choice for Cost-Effectiveness, Lowest Unit Cost
Central inverters focus on high-power scenarios, with a single-unit power generally above 500kW and a maximum of several MW. Their core characteristics are simple structure and low integration. They work in a mode of "centralized inversion after parallel connection of multiple PV strings" and do not require complex refined control modules. Because a single unit can drive a large-scale PV array, the economies of scale are extremely significant, and the number of components and R&D testing costs are greatly shared. The unit power price is the lowest, making it the mainstream choice for large ground-mounted PV power stations, with a unit cost of only about 0.1~0.2 yuan/W.
2. String Inverter: Balanced Adaptability, Medium Price
String inverters are currently the mainstream models for distributed scenarios, with a single-unit power ranging from 3kW to 300kW, suitable for various scenarios such as residential and industrial/commercial rooftops. They adopt a multi-channel MPPT (Maximum Power Point Tracking) design, and each MPPT can independently track the power generation peak of a group of PV strings, which can effectively reduce power generation losses caused by shading between strings and differences in tilt angles. Compared with central inverters, their structure is more sophisticated, requiring additional control circuits, detection modules, and efficient heat dissipation components. The increase in structural complexity directly pushes up the cost, with a unit cost of about 0.3~0.5 yuan/W. The price is at a medium level, balancing practicality and cost-effectiveness, and it is also the first choice for most ordinary users.
3. Microinverter: High Safety and High Integration, Highest Price
Microinverters achieve "independent inversion of a single PV module" with a single-unit power of only 0.3kW~2kW. Their core advantages are high safety and strong adaptability, which can completely solve the power generation mismatch problem caused by shading (such as shading from trees and chimneys on the roof), and there is no risk of DC high voltage, meeting the high safety standards in Europe, America and other regions. However, behind its high value is extremely high R&D and manufacturing costs: a single unit is small in size and highly integrated, requiring strict requirements on chips, circuit boards, and packaging processes, and it also needs supporting safety modules such as module-level shutdown. The cost of a single unit is difficult to be shared through economies of scale, with a unit cost as high as 1.5~2.0 yuan/W, making it the most expensive type for the same power.
4. Energy Storage Bidirectional Inverter (PCS): Functional Upgrade, Obvious Premium
Different from pure PV grid-connected inverters, energy storage bidirectional inverters (PCS) have core advantages of bidirectional control functions such as "charging, discharging, off-grid power supply, and battery management", which can realize the storage and flexible call of PV power, suitable for PV + energy storage systems (for example, to solve the needs of power outage backup and peak-valley electricity price arbitrage). Its price is generally 20%~40% higher than that of pure PV inverters with the same power. The core reasons are: more complex control algorithms, additional modules such as voltage stabilization, current stabilization, and energy storage interfaces are required, and it also needs to adapt to the charging and discharging needs of different types of batteries. Double upgrades have been made in hardware configuration and software R&D. Some high-end models also support peak-valley electricity price management, PV-storage coordination and other functions, further widening the price gap.
(II) Quality of Core Components: Directly Determine the Pricing Level
The stability, conversion efficiency, and service life of an inverter are completely dependent on core components such as IGBT, capacitors, inductors, and main control chips. The brand, material, and performance of the components are the key drivers of cost differences and the core embodiment of "you get what you pay for".
High-end inverters mostly adopt imported (Infineon, Mitsubishi) or domestic first-line brand power devices, with higher conversion efficiency, lower losses, stronger anti-interference ability, and a service life of more than 20 years; accessories such as capacitors and inductors also adopt long-life and high-reliability solutions (such as Japanese long-life capacitors), and the cost is much higher than that of products using ordinary components. At the same time, the application of new material devices such as silicon carbide (SiC) can greatly improve the inverter efficiency and reduce the volume, but the material cost is 50%~100% higher than that of traditional silicon-based devices, which will also directly push up the product price. Low-cost inverters mostly adopt ordinary components, making compromises in efficiency and stability, so the cost is naturally lower, but the failure rate in long-term use is higher, the power generation loss is greater, and it may even increase the later maintenance cost.
(III) Functional Configuration and Intelligence Level: Widen the Premium Space
In addition to the basic energy conversion function, the differences in intelligence, protection, and expandability of inverters will also form an obvious price gradient, which is especially suitable for users with higher requirements on user experience and power generation benefits.
High-priced inverters are usually equipped with practical functions such as WiFi/4G remote monitoring, IV curve diagnosis, PID repair, active arc prevention, and grid support. Users can view real-time power generation data and fault warnings through mobile phone APP, and the background can automatically optimize power generation and repair minor faults, reducing manual maintenance costs; the protection level reaches IP65 and above, which can adapt to harsh outdoor environments such as high temperature, heavy rain, and high humidity, with stronger stability. Entry-level inverters only meet the basic inversion needs, with simplified functions and no intelligent monitoring, and the protection level is relatively low (mostly IP54), which is only suitable for simple scenarios with mild environment and low requirements on power generation benefits, and the price is also more affordable.
(IV) Quality Assurance Service and Brand Strength: Embodiment of Hidden Value
Many users easily overlook that the price of an inverter also includes the hidden costs of brand strength and after-sales quality assurance, which is also the part that can best reflect "cost-effectiveness" in long-term use.
First-line brand inverters (such as Huawei, Sungrow, Ginlong, etc.) not only invest more in R&D and quality control, but also provide a 5~15-year long-term quality assurance, supporting national after-sales outlets and professional technical support. In case of faults in the later period, they can respond quickly and repair in a timely manner, reducing system downtime losses. Low-cost niche brands have a quality assurance period of less than 3 years, or even no clear quality assurance commitment, with scarce after-sales outlets. It is difficult to repair faults in the later period, which may lead to long-term failure of the system to operate normally, and the gain is not worth the loss.
II. Precise Selection Guide: Which Inverter is Most Suitable for You?
After understanding the core reasons for price differences, the key to selection is to "match your own scenario" — there is no need to blindly pursue high-end and high-price, nor can you only look at low-price and ignore practicality. Combining your own installation scenario, power generation needs, and budget, you can quickly lock in the appropriate type. The following gives specific suggestions for 4 types of mainstream scenarios, and ordinary users can find their own match.
(I) Scenario 1: Large Ground-Mounted PV Power Station (Enterprise/Collective Project, Power Above 500kW)
Core Needs: Low cost, large-scale power generation, pursuing maximum unit power benefit, low requirements on refined control.
Recommended Type: Central Inverter
Selection Reason: Central inverters have significant economies of scale and the lowest unit cost. A single unit can drive a large-scale PV array, with simple structure and convenient maintenance, which can effectively control the overall project cost and is the optimal choice for large ground-mounted PV power stations.
Notes: It needs to be used with a combiner box, and is not suitable for scenarios with severe shading and large differences in component tilt angles.
(II) Scenario 2: Residential PV (Household Roof, Power 3kW~20kW)
Core Needs: Stable power generation, convenient installation, high cost-effectiveness, and some users have slight shading (such as shading from trees and balconies).
Recommended Type: String Inverter (First Choice); Microinverter is optional for severe shading/pursuing high safety
Selection Reason: String inverters have a medium price and balanced functions. The multi-channel MPPT design can reduce power generation losses caused by slight shading. They are small in size and flexible in installation, suitable for most household rooftops, and support remote monitoring, which is convenient for users to view power generation status, with the highest cost-effectiveness. If the roof has severe shading (such as dense surrounding high-rise buildings and big trees), or you are worried about DC high voltage safety, you can choose a microinverter. Although the price is relatively high, it can maximize the power generation and safety.
(III) Scenario 3: Industrial/Commercial PV (Factory and Office Building Rooftops, Power 20kW~300kW)
Core Needs: Efficient power generation, stable and reliable, easy to manage, and some factories have local shading (such as shading from equipment and pipelines).
Recommended Type: String Inverter (Mainstream); Small Central Inverter is optional for large unshaded areas
Selection Reason: Industrial and commercial rooftops have a large area and a large number of components. The multi-channel MPPT design of string inverters can adapt to differences in tilt angles and orientations of components in different areas, reducing shading losses, and supporting multi-unit parallel connection, which is convenient for later expansion and management, with strong stability, and can meet the needs of long-term efficient power generation in industrial and commercial fields. If the roof has a large unshaded area and regular component arrangement, a small central inverter can be selected to further control the unit power cost.
(IV) Scenario 4: PV + Energy Storage System (Residential/Industrial/Commercial, Needing Backup Power Supply and Peak-Valley Arbitrage)
Core Needs: Capable of storing PV power, backup power supply in case of power outage, flexible call, and some users want to save costs by using peak-valley electricity prices.
Recommended Type: Energy Storage Bidirectional Inverter (PCS)
Selection Reason: Energy storage bidirectional inverter (PCS) is the core of the PV + energy storage system, which can realize bidirectional conversion of "PV power generation → storage" and "stored power → power supply", support off-grid power supply, and solve the demand for backup power in case of power outage; some high-end models also support peak-valley electricity price management, storing power during off-peak hours and discharging during peak hours, helping users save electricity bills. When selecting, it should be noted that the corresponding PCS power should be matched according to the capacity and type of the energy storage battery, and priority should be given to models supporting PV-storage coordination and battery protection functions.
In short, the price difference between different types of inverters is essentially the difference in technology, quality, functions, and scenario adaptability. Choosing the right inverter can not only control the initial investment cost, but also ensure the long-term stable and efficient operation of the PV/energy storage system, maximizing benefits. If you are still unsure which model is suitable for your scenario, you can contact our professional technical personnel at Demuda: https://www.dmdsolar.com/article/index/id/22.html to get one-on-one selection suggestions.
