Note: In July , SunPower notified dealers it would be halting all new shipments and project installations. The company also noted it would &#;no longer be supporting new Leases and PPA sales nor new project installations of these financing options.&#;
Getting the most out of your renewable energy system &#; solar panels, for example (we&#;ll base this article on solar energy, since it&#;s the most common renewable energy source used) to your home or office appliances, you need to build a fairly intricate system in order to ensure that your appliances are kept running: solar panels connected to a battery, and then finally connected to your various appliances.
Senergy supply professional and honest service.
Grid tie inverters are DC-AC power inverters which, like Pure Sine Wave Inverters, convert the redundant DC power from solar panels into the AC power household appliances run on. However, a grid tie system can take the conversion one step further. Instead of sending the newly generated AC voltage into a battery for storage (explore solar power storage methods), or directly into an appliance, they are tied into the grid (hence the name), and as such, work in tandem with the electricity sent to your home or office from the national grid.
Grid tie inverters bypass the worst of the issues you can face with direct-to-appliance solar set-ups (such as requiring a means of storage, making regular adjustments to match the varying demands of different appliances, etc.) by putting the renewable energy you generate directly into the grid. This has many advantages. For one, if your home or office solar system happens to produce more energy (explore solar panels&#; energy generation capacity) than you actually use, the excess which goes into the grid is (in the UK, USA, and most European countries) actually subsidised by the government or by your energy suppliers, who can use that surplus energy to fuel other homes and businesses. This process is called Net Metering. Moreover, grid tie inverters are designed so that they need only match the grid&#;s waveform and voltage, rather than having to match a wide variety of different appliances. (The overall process is made that bit simpler, in other words.)
In short, a grid tie inverter empowers home and business owners to use an alternative, renewable source of energy to power their buildings without having to resort to extensive rewiring or the use of batteries for storage. The best grid tie inverters match the (pure sine) waveform of the grid&#;s AC voltage, and ensure that they do not overload the grid with excess power &#; which can be especially problematic with solar panel systems during peak sunlight hours. In addition to saving you money on your power bills, such a set-up can actually earn you money, depending on the subsidising initiatives in place in your country or state.
Having reviewed the market, we&#;ve determined the very best grid tie inverters to suit different requirements.
Best Budget
Grid tie inverters are a great cost-saving addition to your home solar system, but they don&#;t often come cheap. If budget is your primary concern, then you&#;ll be glad to know there is a trustworthy brand out there with a grid tie inverter just for you. Y&H have produced this micro-inverter to cover conversion of DC power up to 350 watts. Whilst not practical for any particularly large solar setups, this budget-friendly inverter is perfect for the first-time solar panel owner, who&#;s looking to integrate just a little renewable energy into their house&#;s daily electricity consumption.
Best Power
For those of us looking to harness as much solar power as possible, or for those wishing to build upon an already well-established solar system, you&#;ll need something that can handle the impressive wattage output of your panels. When it comes to power, there is simply no stronger grid tie inverter out there than the SMA Sunny Boy W inverter. At W, this mammoth can handle just about anything your solar panels can throw at it, and shouldn&#;t face any problems even during peak sunlight hours around midday. For any homes and businesses looking to profit off the installation of a grid tie inverter, an inverter like the Sunny Boy is probably your best bet (provided, of course, that you have the solar panel set-up to back it up).
Best All-Rounder
The Marsrock inverter is an impressive-looking piece of kit. With an in-built power limiter and MPPT controller (WiFi optional), it is designed to maximise the efficiency of your solar system and extract the maximum energy from it at all times, feeding that energy in a clean, pure sine wave directly into your local energy grid. At W peak (900W continuous), it&#;s also powerful enough to handle medium-large solar panel arrays, and will help save you money on your electricity bills whilst paying off in the long run, should your home consume less energy than it produces. The Marsrock has several innate protection features, such as over-current protection, thermal protection, reverse polarity protection, and anti-island protection. Budget-wise the Marsrock is a mid-market buy.
There are three types of inverters you can find on the market: chopped, square wave, and pure sine wave inverters. For our purposes, we&#;ll only look at pure sine wave inverters. Earlier models preferred the chopped and square wave mechanics, but these waste a lot of power, are prone to overheating, and &#; worst of all &#; can do damage to the grid if plugged directly into it. This is because in order to feed renewable electricity into the grid, it has to match identically the voltage and frequency of the electricity already on the grid. Mismatches can cause damage and power outages.
Pure sine wave grid tie inverters are located between your renewable array and home. The electricity produced by renewable technology is Direct Current (a straight line, going only one way), whereas the grid&#;s electricity is Alternating Current (a wavy line going both directions). A grid tie inverter therefore converts DC from your renewable sources into AC for the grid, and does so in three stages.
Firstly, a complex system of integrated circuits oscillates the Direct Current from the wind turbine. The current is oscillated to a particular frequency to match grid electricity. In the US, this frequency is 60Hz (or 60 full waves per second). Once oscillated, the current is now AC; however, the waves of the newly created current are too low to power anything of note. Thus, this AC wave is next amplified, until the waves reach peaks powerful enough to be useful. Finally, the pure sine wave grid tie inverter alters the current to ensure that its voltage matches the voltage of the grid, in effect copy-catting the grid into which it is plugged.
A grid tie inverter, on top of actually inverting your DC electricity as described above, continually monitors the grid to ensure that the AC the inverter produces meets grid requirements. It also monitors how much electricity your home is using, ensuring not to overload the grid with too much electricity (especially essential during peak production hours for renewable energies like wind and solar).
Many grid tie inverters come with additional features such as wireless monitoring, in-built protection systems, Bluetooth controls, LED displays and more.
Let&#;s take a look at the fundamental pros and cons associated with grid tie inverters.
Pros:
Cons:
We&#;ve examined our top picks from the market, but there&#;s still plenty of other reputable grid tie solar inverters out there, to power your home grid tie solar system. Let&#;s take an in-depth, pros and cons look at all that the market has to offer.
At a respectable price, the iMeshbean grid tie inverter is a perfect halfway-house between those with large residential solar arrays, and those working with just one or two small solar panels. The grid tie solar inverters produced by iMeshbean are stackable (meaning you can build a system of several of them to service your home), and according to customers perform as advertised. The only really important note to make is that the power meter in the box is reported not to work. As such, whilst the inverter does its job, it is impossible to track and thus control without first purchasing a compatible power meter/controller.
Affordable
Works as advertised
No additional features
Power meter included reported faulty by customers
This low-wattage inverter from Encocy is smart, durable (encased in a strong aluminium shell), stackable, and lightweight. Customers report that the inverter not only works as advertised (unfortunately rare on the solar inverter market), but begins to work even in low light conditions, maximising the efficiency of your solar set-up with its handy in-built MPPT controller. (The MPPT controller functions most effectively when receiving an input voltage from the solar panels of between 37-48V.) Stack a few of these inverters and integrate them into the power grid and you&#;ll find them a reliable ally in your quest to become self-sufficient.
Affordable
Durable and lightweight
Works even better than advertised
No remote control included
No additional features
As a brand, Y&H inarguably prioritise budget over quality, and this is something the potential user should take into consideration before committing to a purchase. Still, to say that Y&H put budget before quality is not to say that the quality is terrible. For how little you pay for this range of inverters, what you get is still pretty impressive. Provided you&#;re only working with a small solar array, then these grid tie systems are super handy. Affordable enough to buy several of them and stack them up, they are reported to work quietly and coolly, without having to implement their fans very often. The drawbacks come from the inverter&#;s efficiency (80% is pretty low compared with the rest of the market), and the fact that the advertised input voltage range is actually much tighter, meaning that you have to be sure of your panels producing around 30V of DC, or risk the inverter not working.
Affordable (most affordable 600W inverter on the market)
Customers generally very happy with use in small solar systems
Work coolly and quietly
DC range not as advertised
Peak inverter efficiency very low compared to market standard of 90%
Y&H not a top-quality brand
We awarded the Marsrock W inverter our &#;Best All-Rounder&#; thanks to its relatively agreeable price point combined with a high AC output wattage. Attractively designed, perhaps the most enticing feature of the Marsrock range is the LCD screen on the front, which provides the customer a live-tracking of the input and output voltages, MPPT efficiency (note that the MPPT controller works most efficiently when receiving between 50 and 90 volts), and output wattage. Where most inverters delivering to the utility grid do not even come with a meter, it is especially refreshing to find one which has a user-friendly meter built into the shell. Most customers report a positive and rewarding experience with the Marsrock range, but do warn that since Marsrock are a Chinese brand, their inverters have not been optimised for the US market. What this means to you, dear reader, is that you may have to do some fine-tuning, and maybe even purchase an additional unit or 220V plug for the outlet in order to synchronise the inverter&#;s output with the requirements of the US grid. Furthermore, note that the power cord supplied is graded only to 110V, not the 220V which the unit expresses.
LCD power meter in-built
Relatively affordable
Lots of positive customer reviews
Comes with a limiter sensor so that you can stop the inverter from putting more power into the grid than you need (useful if no government subsidy system in place)
Want more information on solar grid tie inverter manufacturers? Feel free to contact us.
Not optimised for the US market/grid
Included power cord not sufficient to work with 220V output
DC Input and AC Output operational ranges much higher than market standard (may impede its use in residential photovoltaic systems)
SMA are one of the most trustworthy grid tie inverter manufacturers on the US market today. Their customer support and product service team are the #1 rated team in their field, according to IMS research. The inverter, which generates up to an impressive W, is designed to work with a solar panel array producing around 600V (in other words, a large-very large residential array), and has a peak efficiency higher than any of the other inverters here reviewed (97%, compared to the next highest at 90%). The SMA inverter comes with 3 individual MPPT controllers, meaning that it can regulate separately three different solar set-ups (maximising their efficiency even further, since it doesn&#;t try to run them all through the one MPPT controller). The inverter must be set-up to match the requirements of the grid, but one customer has (though happy with their purchase) noted that this can be a little tricky. Since SMA are geared toward businesses with certified installers, they are not necessarily as prepared to help with DIY installations. As such, it&#;s recommended you turn to a professional for installation help, if you encounter any issues yourself.
Most powerful grid tied inverter on the market
Three individual MPPT controllers built-in
97% efficiency rating
1 rates product servicing team in the PV industry
High customer satisfaction
Does not come with any cabling
May require additional professional help during installation, unlike most grid tie inverters
Most expensive of the available grid tied inverters
And so we return to where we started, with the winner of our &#;Best Budget&#; category: the Y&H 350W micro-inverter. As we stated before, this is not the kind of inverter you turn to if you&#;ve got a medium-large solar array. The usable AC power it produces (peak of 350W) is pretty small, and would only be useful in combination with a few low-energy solar panels. Still, for the money you pay for it, it more than does the job, and has left the majority of its customers satisfied. However, when it comes to quality, Y&H is not the most reliable brand. Customers have reported some issues with overheating, and struggle with the fact that the inverter is designed to work with 24V solar panels (despite 12V being super popular). If budget&#;s the name of the game, then this is most certainly a good starter inverter. Just don&#;t expect miracles.
Most affordable (&#;Best Budget&#;) inverter on our list
Good for first-time solar energy users
Reported issue of unit overheating
Advertised continuous 320W more like 290-300W
Not compatible with 12V solar cells
Buying a grid tied inverter, let alone choosing the best inverter, can be a confusing process at the best of times. Hopefully we&#;ve laid things out pretty comprehensibly in our product guide above, but should you require a little more help when browsing the market, here&#;s a look at the most important things you should consider.
When browsing inverters, you&#;ll keep seeing these two terms pop up. Rated power is the &#;continuous&#; power produced by the inverter according to the manufacturer, which differs from the &#;peak&#; power the inverter can actually handle. Combine this with &#;peak efficiency&#; (of say 90%) and you&#;ll can soon work out that whilst the product has a rated power of, say, W, you&#;re likely to only ever get about 900W out of it.
Having considered the rated power and peak efficiency, you should also consider that solar panel systems are not 100% efficient either. In fact, as standard, a solar panel tends to be about 85% efficient (15% energy lost in the conversion). What this means when it comes to inverters, is that you must ensure your solar panels still produce enough wattage to meet the minimum requirements of the inverter, even after energy loss/efficiency has been taken into consideration. In simpler terms, a solar system of W rating will not be sufficient to work with a W inverter, it must instead produce W when operating at around 85% efficiency. Read our article to explore the energy output from a solar panel.
Different grid tied inverters take different DC voltages. As such, it is absolutely crucial that you first work out the voltage output of your solar system, before purchasing an inverter to match it.
Similarly to the DC input, different inverters produce differing voltages of usable AC power. You must ensure that the inverter you&#;re buying will be compatible with the grid you are planning to tie it to.
Unfortunately, not all inverters on the market come with a power meter built-in, or even included in the box. A power meter is necessary if you wish to run your renewable energy system safely and efficiently, as it allows you to track the inputs and outputs (both voltage and wattage, as well as amps) of your system, and thus correct it if necessary, or at the very least see where faults lie, should faults occur.
If you live in the UK, USA, Europe or Australia, there&#;s a good chance that there is a government subsidy initiative in place, meaning that any surplus power you supply to the grid will either be paid for (making you extra money), or will be offset against your current electricity bill. However, not all world governments have such measures in place, and some in fact charge you for any additional power pumped into the grid. In such places, it&#;s important you buy an inverter with a limiter, to ensure that only the power your home or business requires is filtered into the grid, and no more.
Having studied the market, taking into consideration budget, efficiency, bran reputation and reliability, customer feedback and power, we&#;ve come to the conclusion that the very best grid tied inverter on the market is the Marsrock W PV Grid Tie Inverter & Power Limiter. With the LCD screen monitor built right into the casing, and with lots of positive customer reviews, we know that this is an inverter you can rely on to not only accurately match the requirements of your local energy grid, but to do so efficiently and at a price that won&#;t completely break the bank.
With most of the inverters we&#;ve listed here, you should be able to install them by yourself, just by following the instruction manuals included. However, pure sine wave inverters are not simple pieces of equipment, and we do not recommend that you proceed with installation unaided unless you are absolutely confident in your ability to do so.
Typically, a grid tie inverter will last anywhere up to 25 years, before requiring replacement. You may of course need to service the inverter during this timeframe, but provided you meet its ideal input and output requirements, it should run pretty smoothly for a long time.
Grid tied inverters are designed to automatically break their connection with the grid in the event of a power blackout/power outage, in order to ensure the safety of any workers making repairs on the line.
Without going into the detailed electronics and science behind this answer, in effect transformerless inverters are lighter, smaller, and more efficient than regular transformer-based grid tied inverters. However, transformerless inverters, whilst popular in Europe, have been slow to enter the US market over some concerns regarding their operation in fault conditions.