Small and Light Three Phase String Inverters Appear at Shanghai Expo

omnik solar inverter
Omnik solar inverter

The SNEC PV Power Expo was held from April 28 to 30 in Shanghai, China Thousands of PV industry companies with their own solar products attended the expo. Omnik New Energy from Suzhou, Jiangsu province also appeared at the expo and exhibited its small and light three phase string inverters there for three days.

Omnik is famous for string inverter manufacturing, and so it brought its high efficiency three phase string inverters and and single string phase inverters to the expo, which drew so much attention of the expo visitors. During the three days my colleagues and many customers from home and abroad discussed issues relating to inverters many times, and one customer from India even visited our booth several times to seek a cooperation opportunity.

The inverters brought to the expo were about 10 or so, and the most attractive ones were two: Omniksol-1K/1.5K-M and Omniksol-10K-TL2. The first one is a single phase inverter, while the second one is a three phase inverter. They don’t look special, but they have their special features that are attractive to customers.

Omniksol-1K/1.5K-M is a newly-launched product by the company in 2015. It weighs 5 kg and doesn’t need any transformers as many other inverters need. The highest efficiency of it can even reach up to 95.5% and its MPP tracking accuracy can be as high as 99.9%.

Omniksol-10k-TL2 is also a new product released by the company. This three phase string inverter weighs 22 kg, which is easier to install and transport and can help save cost.

During the three days Omnik also held a product conference to show the two products to customers who came to the expo to collection information and see new PV products. After the three day expo, Omnik’s staff have already established new relations with more customers from home and abroad.


Grid-Tie PV System VS Off-Grid PV System

There are basically three types of solar PV systems existing today for solar power generation at home, including grid-tie, off-grid and hybrid PV systems. However, as expense and efficiency are concerned, grid-tie and off-grid systems are more popular and most installed around the world. Now let’s compare them with each other and help you decide which system should be suitable for your house.

grid-tie solar PV system
grid-tie solar PV system

Grid-Tie System

1. This installation requires your system is connected to the local national (utility) grid.
2. After the connection, the system can feed the electricity (usually extra electricity) it generates to the national grid (this helps it earns money from the grid), and your home can get the electricity from the national grid once your system stops generating electricity at night or in special conditions.
3. The current form your solar panels generates is direct current (DC), which must be converted into alternating current (AC) for home use by going through a PV inverter. The current converted by the inverter must be compatible with the voltage of the local grid.
4. The inverter also needs to be a grid-tie type. An off-grid one cannot be used here.

Off-Grid System

off-grid PV system
off-grid PV system

1. Off-grid means the system is disconnected from the local national grid and cannot feed extra electricity to earn money.
2. This installation needs storage batteries, which usually cost a lot of budget.
3. This system is suitable for installation in areas where houses cannot be connected to the national grid or where residents are far away from grids and cities.
4. It needs a charge controller which is used to charge the batteries of the system.
5. The DC from solar panels usually goes to a battery and then to an inverter.
6. This inverter is an off-grid inverter.

Grid-Tie Advantages

1. It can constantly power your house unless the national grid is down and the system meets its special conditions.
2. It can help earn money from the local government by selling extra electricity.
3. It costs less compared with an off-grid system because it doesn’t need expensive batteries.
4. It works more efficiently because its DC doesn’t to go into a battery. This process causes energy loss.

Off-Grid Advantages

1. It can be used in remote areas where national grids cannot reach.
2. It can store extra energy and use it whenever your house needs.
3. It doesn’t need the grid-connecting process.
4. It is totally environmentally friendly.

Current Condition

In comparison, residents around the world prefer a grid-tie system more, and many countries like the UK, the US, the Netherlands and China are encouraging their residents to install this system. But In India, an off-grid system seems to enjoy more welcome because many regions in the country cannot reach national grids.

5 Basic Tips to Know for Home Solar

Home solar is one invention of the new century, but it has expanded to different parts of the world. Since it becomes so popular, it is possible you may decide to power your house with solar power someday. As for home solar power, there are five basic tips you need to know before you build such a system. Below are the five basic tips for you.

Tip 1: Learn the process of how electricity is generated at home.

To generate electricity with sunlight is not a very complicated process. Generally speaking, you need to install a solar PV system in your house which consists of solar panels, a PV inverter (or microinverters), a two-way meter (optional), batteries (optional), racks, wires and so on. These solar panels function to convert sunlight into direct current, which will the be fed to the PV inverter that converts it into alternating current. Why should it be converted? Because your house’s power system can only consume alternating current.

Tip 2: The system does need a rooftop or a spot on the ground.

Since solar panels are part of the system, and they must be installed somewhere. The common installation area is a rooftop which must be under your name. If possible, the roof had better face south, west or east but never north, for these directions guarantee more sunlight can be absorbed. At the same time a slant roof is better than a flat one for the sake of absorbing more sunlight. This has so much to do with the sunlight angle. Or if you don’t think it is possible to install them on your roof, and your alternative is to install them on a piece of ground that belongs to your house.

Tip 3: Keep a clear idea about the lifespan of the system.

The average lifespan of it is about 25 years, while some business owners say their systems can last for 30 years. Indeed this is also possible if the system is well-maintained by you. Another question is: what is the lifespan of your solar panels? They are really good stuff, for they can last for 30 years or so. The flaw is their efficiency declines as they become old. The last question is: what’s the lifespan of your inverter? The maximum figure is between 10 and 15 years. Therefore, you will have to replace your inverter once during the system’s entire life.

Tip 4: You can keep track of the output of your system.

As solar technology improves, you can use some certain software to monitor your system. By doing so, you can learn how much electricity your system generates each day, month or year. What you do is download some software provided by the solar system installer or supplier on to your PC or mobile phone. The power generation statistics will be automatically transmitted to your devices daily.

Tip 5. The system installer will offer you his warranty.

The warranty usually can be available for 5 to 10 years. Besides, each installer also offers extra maintenance options. This means you can get a longer warranty as long as you pay some money for him. Usually this expense is not that expensive, but this service also differs from country to country. Before buying this service, you should let them clearly tell you how much you do enjoy.

These tips are just very basic ideas about home solar, and can be helpful for some who have no any idea about home solar power. If you need to know more, please consult professionals, who will explain even every detailed step for it to you.

How to install and maintain your PV system?

home PV system
home PV system

How do install a home PV system? This is a question always asked and concerned about by those who wish to go solar. But others think this is not a big issue because installers will help you solve the problem. My answer is you had better learn something about it.

First, you should make your self clear that your community permits this. I have heard that some communities don’t approve this. So, making sure of this will save lots of your energy.

Second, before the solar panels are transported to your home, you need a slant rooftop with an area of at least 30 square meters. The rooftop had better be a slope with a certain angle, for this is the best for absorbing sunlight. If you don’t have such a rooftop but only a flat one, you need racks to support your solar panels with such an angle. Or if you don’t think installing panels on your rooftop is possible, you can also ask the installer to install them on the ground to which you own the property right.

Third, when your panels arrive, you may pick out a spot on your rooftop or ground to install them properly. No matter whether you install them on your roof or on the ground, you should make sure they face south, east or west, so that they can catch the most sunlight and generate the most direct current.

Fourth, install some racks on your roof or on the ground to fasten solar panels. After this process you can install the panels on them in the angles that suit your local latitude condition the most.

After the installation, you may connect your panels to the solar inverter or microinverters for the sake of converting direct current into alternating current. Finally, connect your whole PV system to the local utility grid. If you are intended to do so, you may also need to install the prepared batteries into the system to satisfy the constant power supply for your house. Some who have enough financial support can connect to the grid and install batteries.

Once the installation job is over, you must be considering how to maintain it. To be honest, such a system doesn’t need too much of your time for its maintenance. You only need to make sure the panels are always clean, without anything like bird droppings, dust or snow on them. Three or four times of cleaning in a year is enough, unless you meet special extreme conditions. In addition, make sure your solar inverters are free from dust and moisture.

The Installation Process for a Residential PV System

Solar energy has been used to generate electricity in large solar power plants. As solar technology advances, even a family can generate electricity on its own by installing a small PV solar system at home. It is a new thing and so how to install it in a house still remains a mystery for many who wish to go solar. Now it is time to know how this solar power system is installed at home.

1.Search the web and learn needed information.
No mater whether you search Google, Bing or Yahoo, you had better make clear of two things: the advantages and disadvantages of generating electricity with solar energy and the requirements of installing such a home use power plant. Usually solar power generation doesn’t need biofuels like coal and gas and its costs are relatively low. But in the beginning it requires some amounts of investment. If you wish to install such a system at home, you should at least consider the amount of electricity your family consumes, where its components should be installed, function tests and so on.

2.Investigation on the spot
In common conditions the company you want to hire to do this business for you will send some of its installers to investigate your house conditions. For example, they will need to know the area of your rooftop, the shading area on it, the style of it (some are slopes and others flat), the direction your house faces and so on.

3.Making an installation plan.
By investigating your house conditions, the experts will probably need to make a plan of how to do the job for your family. Different families have different physical conditions, and so the plans will tell the house owner how the work can be done smoothly.

4.Signing a contract with the installer.
After getting the customer’s permission, the two sides need to sign an agreement to protect the profits of each other.

5.Applying for connecting to the utility grid.
You need to wait for the PV devices (including solar panels, a PV inverter, racks, wires and other components) to arrive and apply for installation and inspection by the county or the utility company. The installation usually won’t take long, and then the inspectors will inspect your system and confirm it. After everything is done, the utility company will install a new two-way meter and connects your house’s system to the grid.

6.After installation maintenance.
Usually the system is not easy to meet trouble. If something troublesome occurs, you need to call the contractor and let him do the job for you. For a common installer, this warranty will last from 5 to 25 years.

Solar Power Revolution in India to Be Successful?

Gujara solar power station

As climate change and environmental issues become more and more serious, a solar power revolution is beginning to reshape the world. The UK, the Netherlands and the US have become the giants in this new industry, but how about India, a country that doesn’t seem to be so modern?

The Guardian reports that India’s current prime minister Narendra Modi has an ambitious plan of installing PV power systems in the country. Its current power minister thinks it is not a difficult task to add 10,000MW of solar power a year. This is a large number. For India, can this goal be realized as the minister has publicly said?

The fact is that India today is home to the biggest solar farm in Gujarat in Asia. India’s current renewable energy power capacity is 31,692.14MW, and its solar power capacity is 2,900MW. By this comparison, you must learn how much solar power’s role is in the country and how the country treats PV solar power. In addition, under the supportive solar power installation advocacy from its leaders, solar power begins booming in this developing country.

Besides, the government’s energy policies have also changed somewhat. Mercom Capital Group’s CEO Raj Prabhu says India has changed its policy about coal and ended its anti-dumping policy. According to him, the supreme court has suspended the coal-exploiting license, and more coal needs importing, which makes its cost much higher than ever. At the same time India’s power supply is not enough to sustain the whole nation’s power consumption. Under these beneficial conditions, India’s solar power seems to have a prosperous future.

However, there are still some unpleasant reports. For example, the World Bank’s index reports that India’s economy rank has fallen from 131 to 142. The other true fact is that India’s 80% of crude oil still depends on import. The two things cannot abruptly announce that India’s solar power plan will be affected, while it is possible that this ambition will be influenced.

Monocrystalline Silicon Solar Cells More Popular, More Solar System Installations Expected

Monocrystalline silicon is a relatively dynamic non-metallic element, and one important part of crystalline materials. Today it serves as one of the most important newmaterials, mainly used for making semi-conductor materials, solar cells for PV systems, heating systems and so on. It is also named single-crystal silicon, single-crystal Si, mono c-Si or mono-Si. In the past 30 years, In the recent 30 years, solar energy technology has won great achievements in research, commercialization and market expansion, and will also win its market share in the future.

A few days ago, NREL and the company Crystal Solar worked together and proved that mono-Si solar cells and modules that are less than 80 microns thick. More importantly, they can become less expensive through an epitaxial process. At the same time this process can help grow large numbers of cells, and their cost is about 50 cents each watt. The process shows us that cell cost cost can be halved and 100 times faster than conventional epitaxial reactors. In this case, quick commercialization for single-crystal silicon can be expected.

One data report from some large scale ground PV solar power station in Ningxia, China shows that a single-crystal silicon power station can generate power 5% more than a poly-silicon power station on average.

Single-crystal silicon and poly-silicon are two very important components of a solar PV system. Why are they called single-crystal silicon and poly-silicon? The simple reason is that they have different crystal lattices. People usually think that single-crystal silicon can be made into solar cells that are more potential in generating power. However, the cost is relatively higher. The last data shows that their costs are nearly the same when they are put into a solar PV system. In addition, single-crystal solar panels will be more advantageous in later maintenance and operation.

At present, single-crystal silicon solar PV power generation has been gradually approved, while it still seems its higher cost is now its threshold compared with poly-silicon solar cells.

In China today, single-crystal silicon power stations account for about 10% of the total number, and the rest are comprised of single-crystal silicon and a few thin-film stations. In the past years, the poly-silicon power plants have been prevalent because of its relatively cheaper price.

In the world, single-crystal silicon solar cells are more used. In 2013, new installations have passed 38GW, with 8-9GW of single-crystal silicon installations accounting for 31%-35%. Indeed, this figure is still lower than poly-silicon power installations. But if higher efficiency is considered, this cost evaluation must be changed somewhat.