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As you start to research on solar panel systems, you might start to wonder what solar inverters exactly are. In this article, we’ll take a deep dive to unravel the mystery behind them, and shed light on their crucial role in solar panel systems. Whether you’re a budding solar panel enthusiast or just curious about sustainable technologies, join us as we explore what solar inverters are and why they are essential components to a greener, solar powered world.
To understand what solar inverters are, we first have understand the different types of electricity currents.
There are 2 types of electricity currents, namely alternating currents and direct currents. What solar panels produce are direct currents (DC), whereby electricity only flows in one direction. However, what powers your house are alternating currents (AC), which flow in both directions. As a result, what your solar panels produce cannot be used to power your house.
This is why we need solar inverters – they basically act as a middleman between your solar panels and your home. By converting direct currents produced from your solar panels to alternating currents, your solar panel system will be able to power your household!
Your solar inverter should be located at a place which is both wall-mounted and in a well-ventilated area, shielded from rain and direct sunlight.
The DC output cables of your solar panels will first be combined and run to your inverter. You can choose to either place it near your attic balcony area, or near your DB box located on the ground floor. Most will choose to install them near their attic balcony area as it prevents cable loss between the solar panels and the inverters, which could lead to a drop in efficiency.
After which, the AC output of the inverter is connected to your distribution box (DB). Any excess electricity generated will then be sold back to the grid through metering credit schemes.
A visualization of how we plan where inverters are connectedIn the market, these are the 3 basic types of inverters to be aware of:
As the name suggests, on-grid (also known as grid-tied) inverters are inverters which are connected to the grid. On-grid inverters also allow you to sell excess electricity generated by your solar panel systems back to the grid, helping you net greater cost savings. During the night, or when your solar panel system is down, these inverters draw electricity from the grid instead to power your house. This is where you can explore electricity plans that cover off-peak periods, further maximising savings on your electricity bills.
In countries such as Singapore where electricity grids are generally stable and metering credit schemes are readily available, on-grid inverters are highly recommended.
For us, we use the Huawei SUN2000 inverter, which has one of the highest efficiencies in the market at 98.6%.
Off-grid inverters are inverters that contain their own batteries, allowing them to operate independently off the grid. How off-grid inverters work is that excess energy generated from your solar panels will be stored temporarily within the batteries of the off-grid inverters. This stored energy is then expended at night, or when the solar panel system is no longer producing energy.
These types of inverters are generally recommended in more rural areas, where electricity from the grid might be less consistent and stable. In Singapore, where battery costs are expensive and grid electricity is already very consistent, it is not recommended to get an off-grid inverter.
Offering the best of both worlds, hybrid inverters contain both batteries to store excess electricity & are also connected to the grid. The main benefit of a hybrid inverter is in its ability to store energy that can be used to take advantage of varying electricity rates throughout the day.
However, hybrid inverters are generally not recommended in Singapore as they do come at a steeper price because of the battery cost as well.
When it comes to choosing solar inverters, solar inverters already come in a package with your solar panel system. Therefore, choosing a solar inverter is generally not needed as you can just follow your solar installer’s recommendation, who has a clearer idea on which inverter is the most compatible for your system.
However, it is still good to know what constitutes a good solar inverter for your solar panel system, as shown below.
Relative to your solar panel system, you would ideally want your solar inverter to have a capacity that matches or exceeds the total output of your solar panels. This capacity is typically measured in kilowatts or watts.
This is primarily to avoid inverter clipping, where your inverter is unable to convert excess DC generated from your solar panels to AC due to a limit in its capacity.
However, in situations where your solar panel system is larger than average, your installer might suggest an inverter which is slighly smaller in capacity than your solar array. This is because based on pre-calculations, it would be highly unlikely for your solar panel system to reach its maximum output, hence it would be more cost efficient to get a smaller inverter.
Typically, an inverter’s efficiency will fall between 93% to 99% as it would always require some of the input DC power to run itself. To increase efficiency of your solar inverter, you ideally want a solar inverter that is integrated with Maximum Power Point Tracking (MPPT) technology. MPPT is basically an algorithm which helps to extract maximum available power from your solar panel system under suboptimal conditions, such as hazy, dark or cloudy days. How it does that is that MPPT will take into consideration multiple factors, such as light levels, shading, temperature & more, and attempt to extract the most amount of power.
Whether your house runs on a single-phase or a 3-phase meter also affects what kind of inverter you can install in your home. If your house runs on a single-phase meter, which has limited power capacity compared to a 3-phase meter, you would require multiple inverters of smaller voltages compared to using a single large inverter, which prevents grid overloading.
While this may come at an additional cost & take longer to set up, having multiple inverters is not entirely a disadvantage. In the event one of the inverters breaks down, you are still able to leverage other inverters in the system to draw electricity from your panels.
Inverters typically last around 10 to 12 years, and have a warranty period of 5 to 10 years, depending on how pricey the inverter is itself. Some brands also offer extended warranty options for additional costs if you wish to explore that possibility, but this is provided that you are certain you do not wish to install additional solar panels on your roof in the future or have already maximized your roof space, which will alter your total solar panel capacity.
If you are a homeowner looking to maximise your current solar panel output, you might also want to look into whether your solar panel system is affected by shading. If your solar panel system is connected to a string inverter, you can consider purchasing power optimizers to accommodate for parts affected by shading. Beyond this, there are also other ways to maximise your solar panel output in Singapore, which you can read more here as well.
You also want to look for inverters that offer advanced monitoring features. Some inverters come with built-in monitoring systems or can be connected to external monitoring platforms, allowing you to track your system’s performance and detect issues promptly. Examples of this include Huawei’s FusionSolar app, which instantly alerts you on issues with your solar panel system such as abnormal solar panel temperatures, partial shading and even malfunctioning solar panels.
A common complaint amongst some solar homeowners is that inverters might produce humming or buzzing noises which may be annoying or disrupting. These noises are primarily produced because of the inverter’s fans which help to prevent overheating. If you do see this as a potential issue, you can consider getting inverters with internal cooling systems instead of fans, which are generally quieter and less disruptive in nature.
Just like everything else, there may also be times where your solar inverter might run into performance issues. When these occur, the first course of action should be to always contact your solar installer or technician, and avoid attempting to troubleshoot the problem yourself.
When installed in places exposed to direct sunlight or poor ventilation, there is a high chance that your solar inverter may overheat. This can also occur if proper maintenance is not done, which could lead to loose connections or dusty systems. When overheating occurs, you can consider turning off all non-essential electrical appliances to reduce the load on your inverter.
Isolation faults can also occur to your inverter, which would cause your inverter to shutdown. These occur when the isolation barrier between the inverter’s internal circuit and the grid degrades, which causes an unintentional electrical connection between the inverter’s internal components and the grid.
If you are considering installing a solar panel system yourself but are concerned over the maintenance required to be done for both your system and your inverter, you might want to look into zero upfront cost rent-to-own options. Rent-To-Own allows you to pay fixed monthly fees to install your very own solar panel system, with professional servicing & maintenance , ensuring a 100% worry-free solar experience.
To find out more about Rent-To-Own solar in Singapore, click here!
In the context of Singapore, DIY installation of your solar inverter is illegal and is strictly not allowed. Installing a solar inverter requires direct access to your roof, and this requires proper safety equipment which is not accessible to the average homeowner. Beyond this, testing and commissioning of your solar panel system also has to be conducted by licensed electricity workers from SP, so the possibility of installing solar inverters by yourself is not possible.
Solar inverters are a crucial part of your solar panel system and are the crux to ensuring your whole solar panel system runs smoothly together with your home’s electrical system. Hence, it is of utmost importance to ensure your solar panel system is paired with a high quality inverter to meet the needs of your system.
Are you still in the midst of considering whether to get your first solar panel system? At GetSolar, we have developed a free instant solar simulator to help you gauge how much you can potentially save with solar and how much it costs, with just a single click of a button. Click here to get your free quote today!
While the basic components of any rooftop solar system -- panels, inverters and optional batteries -- stay the same, the cost of solar systems vary from home to home. That's because the size of the system (including the number of panels and batteries and the size of the inverter), the local cost of labor, permitting costs and other factors vary from home to home and location to location.
Residential solar panels cost $3.30 per watt, according to data from the energy consulting firm Wood Mackenzie. That's seven cents lower than the firm's estimate for the year before, but still adds up to $16,500 for a 5-kilowatt system.
Many other factors influence the cost of installing solar panels, including less-than-obvious ones like the complexity of your roof, Rohit Kalyanpur, CEO of the Silicon Valley-based solar company Optivolt, told CNET.
Can solar panels save you money?
Interested in understanding the impact solar can have on your home? Enter some basic information below, and we’ll instantly provide a free estimate of your energy savings.
You can get some help to pay for your panels. The Inflation Reduction Act, passed by Congress in 2022, provides a 30% tax credit for solar panel systems installed through 2032.
Solar panel cost estimates won't map perfectly onto your home. It's impossible to know what an installer will quote you until you actually get the quote. That's why you should always get multiple quotes before moving ahead with an installation.
The cost of a solar system can vary wildly because so many factors are involved.
Cost varies, in part, because of the size of the system, said Neil Gallagher, vice president and co-founder of Brighterway Solar, a Tampa, Florida, solar installer. The solar industry doesn't have a standard pricing structure, so the cost by the customer is based on their energy consumption.
The cost of a solar system installation can vary widely when you compare the efficiency rate of the solar panels and other installation expenses. The best solar panels can set you back anywhere from $15,000 to $50,000.
The 30% solar tax credit provided by the federal government coupled with available state and municipal government tax credits, tax exemptions, rebates and other incentives can further reduce the cost of purchasing and installing solar panel systems.
Different sources yield different cost estimates. In the below estimates, for example, EnergySage draws its information from quotes provided in its solar marketplace while Wood Mackenzie's uses wholesale prices of solar equipment and interviews with industry figures.
*The above estimates are for different periods of time. EnergySage covers the second half of 2023; Wood Mackenzie, the fourth quarter of 2023; and the Lawrence Berkeley Lab, 2022.
Solar costs are also influenced by your solar system's components. Let's break down the components of a solar panel system and what you can expect to pay.
Here's the average total cash price, cost per watt and system size for a solar panel system in your state, according to data from FindEnergy.com. These prices don't factor in tax credits or state incentives. Certain states don't have any FindEnergy solar data and are grayed out on the map.
The table below includes estimated solar savings after the federal solar tax credit, average electricity rates and average annual electricity bills per state, calculated using data from the US Energy Information Administration.
*Electric rates and bills for December 2023.
There are three main types of solar panels: monocrystalline, polycrystalline and thin-film. Monocrystalline solar panels are the most popular choice for residential installation (nearly all residential solar panels installed in 2022 were monocrystalline) because they have the highest efficiency rates from 17% to 22%. The average cost for these panels is between $1 and $1.50 per watt, but prices may differ depending on location.
Polycrystalline panels are popular for homeowners on a budget. They have a moderate efficiency rate ranging from 15% to 17%. Their cost is between 90 cents and $1 per watt.
Thin-film solar panels, which have an efficiency rate ranging from 10% to 13%, are the least efficient solar panels on the market. They have a shorter life span and are rarely used for residential purposes.
Trying to get a solar estimate without an on-site inspection of your home is tricky business. Because the location, layout and energy needs of every home are different, solar pricing for each residence is different too. Your home might need only a small 5 kW solar array. Your neighbor down the street might need a larger 8 kW array, and they might choose to install a solar battery, which is going to push their price tag even higher.
Here are some of the biggest factors that affect the cost of going solar.
Solar installations aren't cheap, but the actual equipment is a relatively small part of the total cost. It's only 35% of your total installation cost, according to the US Department of Energy.
Soft costs, also known as the hidden costs of installing solar, are nonhardware costs, and they make up 65% of your total solar costs, according to the DOE. Most of your soft cost expenses go toward things like sales and marketing, labor, paperwork and overhead profits.
Here are some of the most common soft costs that impact your the final price.
How much solar panels can save you depends on a few things. How much electricity your panels actually produce is impacted by the direction and angle the panels face, how much sun your region typically gets and your system's size. Your utility's policies, like net metering, will have a big effect, too. California's reduced its net metering incentive (and the amount solar panel owners could save) last year, but incentivized the purchase of batteries. Calculate how much you can save before moving ahead.
By investing in a solar system, you're paying upfront to enjoy the long-term financial benefits of reduced or even eliminated electricity bills. It often takes six to 12 years for a solar panel system to pay for itself. Let's take a look at a quick example.
Your breakeven point, also known as the solar payback period, is the amount of time it takes for you to see a return on your investment. In other words, how long it will take for your solar panels to start paying for themselves. Just like the average cost of going solar, your payback period may vary.
Let's say your current monthly electricity bill is $150 and the solar system you want to buy $30,000. First, we want to calculate what your system will cost after the federal 30% tax credit. Here's how that looks:
Now we need to calculate the payback period to know how long it will take to recover the cost of installing the solar system.
Based on this calculation, a $21,000 investment in a solar system will take less than 12 years to recover your initial investment. (Not everyone will be able to reduce their energy bill to zero.)
There are several factors to consider when assessing the benefits of solar panels, Kalyanpur said. First, consider the total energy produced over the system's lifetime and whether it can result in substantial savings. Other factors include state-level incentives that help to offset the costs of investing in solar panels.
Pros
Cons
There are various ways you can go about paying for solar panels. Here are a few of the most common:
Cash: If you can afford it, paying cash is your best option. You won't have to worry about high financing fees or interest rates, and you'll always be eligible for tax credits and incentives. Your solar payback period will likely be shorter, too.
Solar loan: Paying thousands of dollars upfront in cash isn't an option for everyone. If paying cash isn't in your budget, your installer might offer you a financing option called a solar loan. These loans are usually through a third party, so check for associated fees and interest rates.
Other loans: A solar loan isn't your only financing option. You could consider taking out a personal loan through your bank or opening a home equity line of credit. Just be aware of the risks that come with a HELOC. If you can't pay back what you owe, you could lose your home.
Lease or power purchase agreement: If you aren't interested in solar panel ownership, consider leasing a system or entering a power purchase agreement. When you lease a system, you pay for the use of solar equipment owned by a solar company. Entering a PPA means buying solar power generated by a company-owned system at a fixed rate. This fixed rate is usually cheaper than the retail electricity rate from your local power company. Ask your solar installer about all your options.
It can take six months or more to get solar panels installed. The actual "installation" of the panels on your roof by the installer is usually completed in three days or less.
What really slows down the process of solar installation is everything that needs to happen before installation day. The sale of the system itself, site assessments, system design, gathering permits and supply chain issues can all drag out the solar installation timeline. Most of your time will be spent waiting around for permits and paperwork to be approved, as well as dealing with supply chain delays.
Often. In most cases, solar panels are viewed as upgrades or home improvements. Installing solar panels could increase your home's resale value by about $15,000, according to the DOE.
Solar panels can last upwards of 25 years or more. The longevity of your solar panels depends on environmental conditions, the type of panels installed and the quality of installation. Many solar companies also offer 25-year panel warranties.
There isn't a definitive "best solar state," but there are states that make going solar more affordable and accessible by providing state-level tax incentives and rebates. States with net metering and a Solar Renewable Energy Credit, or SREC, market even make it possible to earn money by selling your excess solar energy to the power grid or utility companies. Solar panels will generate more electricity in states that receive more peak sunlight hours.
Installing solar panels on your home can significantly lower your electricity bill, raise your property value and reduce your carbon footprint. The biggest downside to going solar is how much it's going to cost. Solar can have a lot of expensive upfront costs, and installing a battery with your solar panel system will likely cost you $10,000 or more.
Correction Aug. 18: This story originally presented some statements as direct quotations that were actually paraphrases of what the individual cited had said. Those passages have now been rendered appropriately as paraphrases.