A solar power system is more than just a few fancy panels attached to your roof or set up in a sunny position on your property. One of the most important components to your solar power system is the inverter.
A solar inverter, or sometimes solar converter or a PV inverter, converts the variable DC output of a PV (photovoltaic) solar panel into an AC current that can be used by a commercial power grid or by can be fed back into your own off grid network.
How do Inverters work?
In simple English a solar inverter works in this way:
- The sun shines down onto your solar panels. Your solar panels are cells that are made of semiconductor layers of crystalline silicon or gallium arsenide. These layers are a combination of both positive and negative layers, and they are connected through a junction.
- The semiconductor material absorbs the sunlight and transfers the light’s energy to the PV cell. This energy knocks electrons loose, and they move from one layer to the other, thereby producing an electrical current. This is a direct current (DC).
- This energy is then stored in a battery bank for later use or sent directly to an inverter, depending on your set up and type of system.
In order to use this generated energy within a residential setting, the energy needs to be converted from DC power to AC power as all home appliances require an AC power supply. This is where you need an inverter.
The inverter takes the DC energy and runs it through a transformer. The inverter runs the DC energy through two or more transistors that are rapidly turned on and off and feed two different sides of the transformer. This in turn creates AC power which you can then use, store or send back to the power grid.
Types of Inverters
There are generally three broad types of solar inverters available for your system:
- Stand Alone Inverters
- Grid Tie Inverters; and / or
- Battery Backup Inverters
Each type of inverter has a specialised function and it is important to have the right type of inverter for your system to get maximum benefit from your investment.
Stand Alone Inverters: These are used in systems where the inverter needs to draw DC energy from batteries that get charged by the photovoltaic arrays (solar panels). Quite often, stand-alone inverters will also incorporate integral battery charges which can refill the battery from an AC source.
Grid Tie Inverters: These are designed to shut down automatically upon any loss of power from your power company supply. This is for safety reasons. If you have a Grid Tie Inverter you will have no backup power if there is a power cut from your power supplier (ie Vector, Meridian, Genesis, etc)
Battery Backup Inverters: These inverters are designed to draw energy from a battery. They manage the battery charge via an on board charger, and then send any excess energy back to the power grid.
What are the Advantages and Disadvantages of having a Solar Inverter?
Without an inverter it is impossible to create the right type of energy to be used in your home with your appliances so the biggest advantage to having an inverter is being able to run your home as if you were still connected to the national grid.
We categorised inverters (above) into three generic types – however within these types you can also choose centralized string inverters, micro inverters or power optimisers. What are these? Centralized string inverters are the most common technology option for rooftop solar panel systems however micro and power optimizers have gained popularity in recent years.
Advantages of Centralised, Micro and Power Optimiser Inverters:
- If you are looking for the most affordable option – you need a centralised string inverter. They function best if you have your solar panels installed on your roof.
- If your solar panels are installed on a shaded part of your roof, or you have many angles to your roof and the panels are spread out across the angles then a micro inverter or power optimizer will give you the best results.
- Micro Inverters and power optimizers are more efficient than a centralised string inverter and if you have either of these types installed then you will receive slightly higher amounts of energy from your system than if you have a centralised string inverter.
- If one of your solar panels in your system is underperforming, a Micro Inverter or a Power Optimiser device will ensure that your system still produces a substantial amount of power. If one panel fails, the others will still continue to produce electricity IF you have a Micro Inverter or Power Optimiser Inverter installed.
- Because Micro Inverters and Power Optimisers are both relatively new technology, they also have the ability to allow you to monitor the performance of individual solar panels, through your smartphone or via a web portal.
- They typically come with longer warranties than string inverters – up to 25 years when they are integrated with solar panels. String inverters are usually warrantied for 10 years and will typically remain operational for about 15 years before needing to be replaced.
Disadvantages of Centralised, Micro and Power Optimiser Inverters:
The potential disadvantages of micro-inverters and power optimizers have to do with maintenance and reliability, rather than how well the devices convert DC electricity to AC.
- With a central string inverter, you can experience a substantial drop in overall system power generation if a single panel stops producing power.
- Both Micro Inverters and Power Optimisers have higher costswhen compared to centralised string inverters, because they require more pieces of equipment.
- With micro-inverter and power optimizer systems, all or most of the critical equipment sits on the roof through rain, snow and heat. By comparison, string inverters are generally located off the roof.
One of the most common types of solar system available these days is the grid connected system. What is this system and what are the benefits? Here we will discuss these and why you should consider a grid connected solar system for your home.
The main feature of the grid connected solar system is that it is connected to the main power grid. This means a number of benefits, from the lack of need for storage batteries to the potential to actually get paid for the power your system produces and feeds into the system. So how does this all work?
A grid connected solar system works by power being produced through the means of Photovoltaic solar panels, which is then fed into the your home’s power system which is hooked up to the mains power grid. How much your system produces and feeds into the system is monitored as well as how much you use, and any extra is fed into the mains power grid. Depending on your electricity company, this power is then credited back to you. If your system doesn’t produce enough power, you have the option to use the mains power. You are not cut off, as you would be with an off grid system. The other benefit is that you don’t need to have any batteries to store the power you produce with these types of systems, which means less upfront costs and less parts to maintain.
Grid connected systems are ideal in areas where you have access to the mains power grid, such as suburbs or inner city homes. If you live in a main city, these systems are perfect for you. Get in touch with us if you would like to discuss the options for a grid connected solar system for you home.
There are many reasons why people choose to go solar, but improving the environment and cutting energy costs are the most common. Many people are aware that solar is a great home efficiency upgrade and are eager to reduce their carbon footprint while also improving their property value.
Whether your motivations for going solar are economic, environmental, or personal, understanding solar energy and how it works and can benefit you is important.
All solar energy systems rely on receiving radiation from the sun to operate. There are two forms of radiation involved in solar energy: Shortwave radiation and Longwave radiation.
Shortwave radiation (visible light) contains a lot of energy; longwave radiation (infrared light) contains less energy than shortwave radiation (shortwave radiation has a shorter wavelength than longwave radiation).
Solar energy enters our atmosphere as shortwave radiation in the form of ultraviolet (UV) rays and visible light. The sun emits shortwave radiation because it is extremely hot and has a lot of energy to give off. Once in the Earth’s atmosphere, clouds and the surface absorb the solar energy.
Solar energy is one of the most renewable and readily available sources of energy we have. We can take for granted that we will always have heat and light from the sun but without harnessing it correctly we cannot garner its energy for practical use. One way of harnessing solar energy is by using it to produce electricity.
This technique requires the use of Solar Photovoltaic (PV) devices or solar cells that convert the sun’s energy into electricity. Photovoltaic devices produce electricity when the sun’s radiation hits these cells and is converted to direct current (DC) energy. This DC energy travels to an electrical device called an inverter, which converts DC energy into alternating current (AC) energy. The AC electricity produced is just like the power supplied by your utility company, and can go directly to power things like computers and lights, or the power produced can be exported back to the mains national electricity grid and get redistributed around the country.
The second way to harness solar energy is by using a solar thermal collector device. These devices harness heat by absorbing the sun rays. This technique is best used around your home for use such as to heat water heaters, hot tubs, and swimming pools.
The most popular way to convert solar energy to electricity is to install Photovoltaic (PV) cells or PV Solar panels. These cells capture the sun’s shortwave energy and convert it into electricity. These solar cells are made of materials that show photovoltaic (light & electricity) effect, meaning that when the sun rays strike the PV cell, the photons of light trigger the electrons inside the cell and start them flowing from side to side in the cell, ultimately producing electricity.
Once solar energy has been converted into electricity, there is no down time – it can be instantly used to power lights or many other devices. Better still, it can be stored in batteries for future use. Although solar power is usually generated into direct current (DC)-type electricity, it can also be converted into AC (alternating current) using a device known as an inverter.
Depending on how Solar energy is captured and then used, there are two ways to categorize it. Solar energy can be referred to as as active or passive solar energy. In active solar energy, special solar heating equipment is used to convert solar energy to heat energy whereas in passive solar energy the mechanical equipment is not present. Active solar include the use of equipment.
Passive solar technologies convert solar energy to heat energy without use of equipment. It is mainly the practice of using windows, walls, trees, building placement and other simple techniques to capture or deflect the sun for use. Passive solar heating is a great way to conserve energy and maximizing its utilization.
By lowering your power bills, these systems not only pay for themselves over time, but they help reduce the air pollution caused by big electricity companies. Contributing clean, green power from your own solar electric system helps create jobs and is a great way to mitigate the pollution and other problems produced by electricity derived from fossil fuel. Solar-powered electrical generating systems help you reduce your impact on the environment and save money at the same time!
More solar energy hits the earth every hour than we need to power the earth for an entire year. That’s 430 quintillion Joules! Solar PV and Solar Water Heating combine this wildly abundant resource with technology and have been in development since the 1860s.
With increasing performance of up to 24% efficiency in modern PV panels, it’s easy to see why so many people are going Solar. Solar Water Heating is so efficient that it can be viable year-round. Its main purpose is to reduce electricity consumption, with efficiencies of up to 85% it’s a quick way to cut electricity bills and save over $1000 per year for the average New Zealand household when compared to electrical only water heating. With water heating systems starting from $5,500 including installation the buy-back periods have decreased significantly, which may well account for the rise in popularity in recent years.
The latest solar water heating systems use evacuated tubes and are designed to blend into most roofs. These tubes have revolutionised the solar industry in recent years and can now be attached to an existing hot water cylinder. They act like double glazed windows to stop heat loss and as the water is kept insulated throughout the whole process, solar energy is gained even in low temperatures.
The best time to install Solar PV (electricity) is once the household has taken energy efficiency measures for example solar water heating, double glazing and insulation. This ensures that the energy generated is being used efficiently, and that the electrical loads are better managed.
Solar system set ups vary depending on each individual household needs, so it’s best to speak with a solar company who is able to advise on the best option for your needs and provide some holistic solutions.
If you would like more information about Solar and how it could work for you, feel free to get in touch with Sunshine Solar – [email protected] 0800 SUNSHINE
Another big decision to be made when deciding to go with a solar system is whether you want solar water heating or solar electric system. Here we will outline the benefits of both.
Solar electric systems are designed to use solar power to provide power to your home through the means of PV solar panels. They either make use of batteries or the mains power grid (as discussed in our previous blog post about on grid vs off grid solar here) to store the power they collect from the sun. These systems can greatly reduce and sometimes eliminate your energy costs, depending on how much sun is available and the design of your system.
Solar Water Heating
Solar water heating systems are designed to use the heat provided by the sun to heat your water through the means of solar thermal panels mounted on your roof. The water circulates through the panels and the system to heat up and then is stored in a hot water cylinder. These systems work to replace gas water heaters or electric water heaters, and both have their advantages and disadvantages.
Can you have both system in your home? Yes you can. However, they are separate systems and cannot be combined into one. It is recommended if you want to heat your water through solar to get a solar water heating system for the water, and a solar electric system for all other electrical needs in your home.
When selecting a solar system for your home or business, the biggest question always asked is should I go with a grid connected or off grid system?
The biggest deciding factor to the answer to that question is generally where your home or place of business is placed, rural or city centered. Grid connected systems need to be connected to mains power, therefore require a mains power system to be available.
Grid Connected Solar Systems.
Grid connected solar systems work without batteries to store their power. Rather, they are connected to the mains power grid and feed the grid with power. You then use your solar power to power your home and don’t get billed unless you exceed the amount of power your system has made. The benefit to these systems is that your power is immediately available, and if you don’t produce enough power you still have electricity available. The mains power grid essentially acts as a maintenance free battery that provides instant, unlimited power.
Off Grid Solar
Off grid solar systems are fully disconnected from the power mains and rely on batteries to store their power. During the day when the sun is out, the batteries get charged at the same time your home gets powered. At night, and on rainy days when the sun is not out, the power stored in your batteries is then used to power your home. There is no connected to the main power grid.
Off grid systems tend to cost more than grid connected systems mainly due to the battery cost. While the other aspects of the solar system as similarly priced, batteries continue to be rather expensive. So while the off grid system is generally quite appealing due to it’s benefits, a bigger initial investment is often required.
Solar is becoming more and more popular these days with an increasing number of people considering converting to a solar system for their home. So what actually are the benefits of a solar system?
Solar is a free energy which everyone can take advantage of with the use of a solar system. Solar can provide a considerable saving on your power bill, especially when used for water heating since that is a large portion of your electricity bill.
Not only that, but solar is the greenest energy production system available, keep things clean and healthy for both you and the environment.
If you live in a rural area, solar is even more beneficial to you through the use of an off the grid system.
Having a well designed system is the key to maximising efficiency and in return, maximising your savings. As experts in the solar field, we are able to work with you to figure out your exact requirements and design a system that will work best for you. Talk to us today and let us find the solar solution y
ou are looking for.