Date: 2023-05-18 hits: 1619
A solar inverter, also known as a photovoltaic (PV) inverter, is a type of power inverter which converts the variable direct current (DC) output of a photovoltaic solar panel into a utility frequency alternating current (AC) that can be fed into a commercial electrical grid or used by a local, off-grid electrical network. As an essential component of a solar energy system, it is used to ensure that the generated solar power is suitable for use in home appliances or supply distribution systems. Generally solar inverters are available in different sizes and types depending on the specific requirements of a solar power installation.
A solar inverter is mainly composed of DC input, AC output, transformer, a cooling system as well as a control system, all of them work together to ensure the normal operation of the solar inverter.
What is DC input?
DC input, a place where DC electricity produced by the solar panels is connected to the inverter, can handle a voltage range determined by the specifications of the inverter and should match the voltage produced by solar panels. It also features a circuit breaker or a fuse that protects the inverter from overloading or short-circuits. Most importantly, solar inverters use maximum power point tracking (MPPT) to get the maximum possible power from the PV array.
What is AC output?
AC output is designed to convert DC power generated by a solar panel into usable AC power, which is also referred as the maximum power output or the rated output power and dependents on many factors such as temperature, humidity, and the amount of sunlight available for the solar panel to generate DC power. Therefore, AC output plays an important role in ensuring that the AC output of the solar inverter is sufficient to meet the power requirements of the electrical load.
What is transformer?
Transformer functions to convert the DC output of the inverter to AC power that can be fed back into the grid. And it can help energy generated by the panels fed back into the grid to improve the efficiency of the solar inverter. Historically, there have been concerns about having transformerless electrical systems feed into the public utility grid. So transformer is designed to provide isolation from the grid, any faults or shorts in the inverter will not affect the electrical grid. Moreover, the transformer also ensures that the AC output of the inverter is synchronized with the voltage and frequency of the electrical grid, so that the power generated is usable by other consumers on the grid. Nowadays, the inverters mainly use the newer high-frequency transformer.
What is a cooling system?
AS an essential component of a solar inverter, the cooling system is specially designed to dissipating the heat generated by the inverter during its operation. It can be divided into passive cooling and active cooling. Compared to passive cooling, active cooling is more suitable for bigger inverters and can regulate the temperature more accurately. Additionally the active cooling system can be further classified into
into air-cooling and liquid cooling. In total, air-cooling is more cheaper while liquid cooling is more expensive and efficient.
Be used to manage the power flow, a control system mainly consists of a micro-controller or digital signal processor (DSP), power electronics and sensors. As the brain of the control system, micro-controller or DSP continuously monitors the PV array voltage，the battery voltage, state of charge (SOC) as well as the grid voltage and frequency. Power electronics achieves the conversions of power through various types of power conversion topologies. While the sensors provide feedback signals to the micro-controller or DSP, which enable closed-loop control of the power converter.
The first generation of solar inverters was developed in the 1980s with limited to a few kilowatts of power output. However, advancements in power electronics and digital control technology in the late 1990s enabled the development of more efficient and reliable solar inverters. And then in the early 2000s, the second generation of solar inverters was introduced with power conversion capability and started to be widely adopted in the solar industry. The third generation of solar inverters emerged in the mid-2010s and were characterized by higher power density, improved power conversion efficiency, and advanced features such as enhanced monitoring and control functionality. Nowadays, with the development of technologies, hybrid inverters become a new trend through combining solar and energy storage functions into a single device to promote a shift towards a more sustainable and clean energy future.
Generally speaking, solar inverter can be divided into four kinds: off-grid inverters, on-grid inverter, battery backup inverter and intelligent hybrid inverter.
l Off-grid inverter is used in stand-alone power systems where the inverter draws its DC energy from batteries charged by photovoltaic arrays. And it is usually equipped with a built-in battery charger to store excess energy produced during the day for use when needed. Normally these do not interface in any way with the utility grid, and as such are not required to have anti-islanding protection. As for its advantages, this kind of inverter is designed to handle the fluctuations of sunlight and deliver a steady, reliable source of AC power, you can also generate the electricity without relying on the power grid, which can be especially useful if you live in a remote area where grid access is limited. However, nothing is perfect, its limited capacity,battery life and compatibility should be worthy of attention. At the same time, its extensive applications are noteworthy. Firstly, it can be used in off-grid solar systems that are not connected to the electrical grid, and these systems are commonly found in remote cabins, boats, and RVs.
In addition, off-grid inverters are used for mobile power solutions like camping, boating or road trips to power portable devices, lighting, and refrigeration. Meanwhile they are also widely applied into emergency backup power, renewable energy systems as well as remote monitoring systems. Based on the quality, off-grid inverters can be further divided into pure sine wave and modified sine wave，pure sine wave inverter produces a higher quality AC output that is similar to the power available from the grid and is more suitable for some sensitive electronic devices when make comparison to modified sine wave.
l On-grid inverter is designed to synchronize with the grid's voltage, frequency, and phase to maintain a stable supply of electricity. The anti-islanding protection measures of the off-grid inverters help shut down automatically upon loss of utility supply for safety. Many on-grid inverters are designed to be connected to a utility grid, and will not operate when they do not detect the presence of the grid. They contain special circuitry to precisely match the voltage, frequency and phase of the grid. For years, on-grid inverter has gained popularity because of its various benefits. For example, it allows customers to save on costs and avoid the risk of power outages. In the mean time, it don’t need additional equipment such as batteries and has higher efficiency ratings compared to off-grid inverters. Based on these,it’s widely used in public areas, such as commercial properties, government facilities,agriculture and so on.
It is well-known that public areas are designed for leisure activities and are open to all members of the community, offering a range of amenities and services, which requires large amounts of electricity usage that leads to high electricity bills. Therefore, the use of on-grid solar inverters in commercial properties has become popular in recent years due to their efficiency and cost-effectiveness. This process also allows customers to generate their own electricity from renewable sources, reduce their reliance on fossil fuels and lower their energy costs.
l Battery backup inverter is a special inverter which is designed to draw energy from a battery, manage the battery charge via an onboard charger, and export excess energy to the utility grid. This inverter is capable of supplying AC energy to selected loads during a utility outage and are divided into grid-tied battery backup inverters,off-grid battery backup inverters and hybrid battery backup inverters. Due to these specifications, the battery backup inverter provides continuous power supply during power outages and power surge protection to protect appliances and electronics from damage. And its portability also makes it the first choice for outdoor activities. And in remote locations, battery backup inverter is used to generate power for various applications where access to a power grid is not available or feasible.
For example, in mining sites or oil rigs, battery backup inverter is used to power telecommunication equipment, and scientists conducting research in remote locations often rely on battery backup inverters to power their equipment, such as monitoring stations, sensors, or data loggers. When meet with emergencies, such as natural disasters or accidents, battery backup inverters can be used to power essential equipment, such as medical devices, communication systems, water pumps, and lighting systems with the aim to improve response times and save lives.
l Intelligent hybrid inverters, also known as hybrid solar inverters, are a type of inverter that can convert DC power from solar panels into AC power for use in the home or to supply excess power back to the grid. These inverters are unique in their self-consumption with the use of storage, which is beneficial to the continuous supply of power during blackouts or power shortages. It also plays a role in preventing the grid from overloaded during peak demand periods and that energy is efficiently distributed to where it is needed the most. When it comes to the usage, intelligent hybrid inverter is usually used in solar power applications using renewable energy for home consumption, especially for solar photovoltaic installations. Electricity from solar panels is generated only during the day, with peak generation around midday. Generation fluctuates and may not be synchronized with a load's electricity consumption.
The growing adoption of renewable energy sources in tandem with regulatory measures by governments to minimize harmful emissions has led to a rapid growth in solar inverters, especially the growth of central inverters, which are expected to dominate the market and allow PV arrays based on a maximum voltage of 1500V,while at the same time require fewer BOS (balance of system) components.
More off-grid inverters emerged into the market this year, specially at those places where power outages are more common, such as Pakistan, the Philippines, and South Africa, c. In response to it, know-how from less grid-stable places became more useful. What’s more, with increasing investments in the renewable energy sector and an upsurge in the deployment of solar inverters against conventional microinverters, the residential solar PV inverter market forecast is expected to remain strong in the years to come. For example, according to the reports by Global Market Insights Inc., the residential solar PV inverter market will depict growth of 4% CAGR through 2028. If looking towards new technologies, silicon carbide semiconductor PV inverters continue to show considerable opportunity for the industry, but electric vehicles control the demand, costs remain high, and IGBT-powered inverter topologies in solar remain the dominant type.
As for countries, Asian countries like India and China were termed to be the largest contributors to the growing market demand. With rapid adoption of green energy, solar-grid integration is now a common practice worldwide,so the Australian Energy Market Operator (AEMO) has published a report focusing on speeding up the introduction of grid-scale inverters to back up Australia’s future power system in its transition to inverter-based resources like solar PV.
However, technical drawbacks of string inverters are expected to hamper the growth of the solar PV inverters market during the forecast period. In conclusion, opportunity comes along with challenge, new and better inverters came to market at all classes from a flourishing industry, but choke points remain for key components including insulated-gate bipolar transistors (IGBTs) and advanced chips.
High commodity prices and supply chain bottlenecks led to an increase of around 20% in solar panel prices over the last year. However, meeting international energy and climate goals requires the global deployment of solar PV to grow on an unprecedented scale. Critical sectors such as polysilicon, ingots and wafers would attract the majority of investment to support growing demand. While at the same time solar PV’s demand for critical minerals will increase rapidly in a pathway to net zero emissions.
Today, China’s share in all the manufacturing stages of solar panels (such as polysilicon, ingots, wafers, cells and modules) exceeds 80%，so the world will almost completely rely on China for the supply of key building blocks for solar panel production through 2025. However, the high level of geographical concentration in global supply chains, and trade restrictions have led to an increased focus on local manufacturing of solar and energy storage, particularly in the United States and Europe. An emphasis on reducing reliance on imported gas has caused renewable energy to become the center of energy supply strategies.
It is also worthy mentioning that in 2023, distributed solar will spread to new consumer segments and gain ground in new markets. New types of households and small businesses will gain access as shared solar options become available, and PV systems are expected to increasingly be attached with energy storage.
The global solar (PV) inverter market size is expected to reach $17.9 billion by 2030, registering a CAGR of 8.8% from 2021 to 2030，which depends on several factors.
End-User Analysis
By end user, the utilities segment holds the largest share, in terms of revenue, and is expected to grow at a CAGR of 8.3%,which is contributed by the increase in investment in the utility scale solar power plants, solar parks, and other solar structures. In addition, rise in construction projects such as decentralized solar power plants, rural electrification projects, solar power plants on the water body & rooftops, commercial buildings, and others drive the growth of the solar (PV) inverter market for the utilities segment across the globe.
Product Type Analysis
By product type, central inverters are expected to dominate the market because of the increasing investment in commercial & industrial projects across the globe and the incentives of governments.
Phrase Type Analysis
By phrase, the three-phase inverters, trending to be equipped with 1,500-volt solar arrays, are anticipated to maintain its dominance, which is attributed to the gaining importance from power generation, distribution, and transmission sector.
Regional Analysis
Asia-Pacific garnered the highest share in the solar (PV) inverter market in 2020, in terms of revenue, and is anticipated to maintain its dominance during the forecast period. This is attributed to the presence of key players and huge consumer base in the region. For example, China is home to the world’s 10 top suppliers of solar PV manufacturing equipment.
When buying an optical solar inverter, not only the price and quality must be considered, but also the stability and reliability, and whether it can meet the requirements of network equipment compatibility and data transmission.
l Capacity
The capacity of the inverter is the maximum load that you can be connected to the inverter. When selecting a inverter, it is necessary to choose the one you need.
Inverter needs to work together with a battery, so check the battery capacity for how much a solar invert can offload and what loads can be supported when there are power outages can help to avoid unnecessary troubles.
Usually an inverter needs to supply two types of power – peak power and usual power, peak power refers to the maximum power that the inverter can supply while usual power is what the inverter has to supply on a steady basis.Therefore, both of them should under consideration.
MPPT tracks and optimizes the solar panels for this sweet spot (Maximum power point) to get the maximum power output from the Solar panels, which is also a important point for consideration.
l Programmable Controls For Regulation And Monitoring
The output of solar panel is not steady due to many factor, so a inverter is needed to regulate the output to ensure steady power output. Accordingly, when buying a inverter, check if there are programmable controls in the form of display panels or there is support for mobile apps for monitoring of power from the solar panels.
With so many solar inverters in the market, it goes without saying you need be aware of the intricacies involved in buying Solar inverters. Hope the above information will be helpful.
