Recently Delta Electronics announced that its new H10E inverter had arrived on Australian shores which is great news for both the industry and consumers alike. Arriving sooner than expected the H8E (8kW) and H10E (10kW) are single phase inverters that come with a variety of innovations but perhaps the most groundbreaking is the inclusion of 4 x MPPT (Maximum Power Point Tracking).
Maximum Power Point Tracking (referred to herein as MPPT) is a feature of grid tied solar inverters that makes sure your solar panels are always working at peak efficiency despite any unfavourable conditions the panels might be experiencing. No matter the stated output of a solar panel it will generate variable voltages depending on external forces such as shade, temperature of the panel and the electrical characteristics of the load.
As these factors impact panels at different rates and times the load that is giving the most efficiency in power transfer changes. The point at which the transfer achieves the highest efficiency is called the maximum power point (MPP). MPPT is in charge of finding the MPP and locking it in until variables change where it will again make adjustments to the load to find the new MPP.
This can be tricky though because the MPP is constantly moving throughout the day as different factors come into play such as panels getting shaded in the afternoon or the increase and decrease in temperature. These factors change the voltage produced by the solar panel and this impacts the current (Amps) generated by the panel. We can see what a solar cell can generate in amps based on its current voltage by looking at the I-V curve graph for the particular solar panel we are using.
Taking a look at the example graph we can see what current is flowing from the panel at any given voltage. In order to get the most efficiency possible out of the panels we need to get to the point where the voltage times the current is the highest which typically happens where the bend occurs as shown by the upwards line. Once the MPPT determines this point its job is to adjust the inverter so that it operates on the MPP.
As mentioned above the MPP is constantly changing. If the panels raise in temperature the MPP will shift and therefore more adjustments need to be made in order to get the most out of your solar power system. As each shift presents a different curve to the one shown in the example there is an almost infinite amount of possible MPP’s. This means your MPPT is constantly working for you.
It’s very common for a solar panel setup to be spread out across several parts of your roof. This can be due to space, shape and what parts of your roof are facing certain directions. When panels are set up like this they are arranged in what we call “strings”. As each string is going to be opening with different IV curves we need a MPPT for each string to make each part of the system get the best performance as a whole. So while other inverters can limit the amount of strings, and therefore total panels, on your roof, the H8E and H10E provide support for up to 4 which is more than enough.
While a lot of this can be seen as confusing abbreviations the role of a MPPT can also be explained by the much used hose comparison. As far as we know the first instance of this explanation dates back to 2013 from the website Quora.com.
In this explanation we compare a MPPT to your thumb placed over a garden hose. If you keep the end of the hose completely covered nothing gets through. If you remove your thumb completely you get the maximum flow but it doesn’t go very far. By putting your thumb over part of the opening the pressure (in this case pressure = voltage) goes up and the stream is able to reach further. The MPPT is looking for the best placement of your thumb to get the most optimal flow over the required distance.
What complicates this is while water from your hose is delivered at a constant rate the power from solar panels is not. So let’s imagine that the hose is drawing water from many pumps (panels) that are all directing water to you. These pumps vary the amount of water they contribute (panels being shaded, temp changes etc) so the amount of water being delivered is constantly changing.
Let’s say you are trying to water a plant or wash a car that’s about 15 feet away. You will need to keep adjusting your thumb placement in order to make sure you are not falling short or overshooting the goal. In this case the plant or car is the Maximum Power Point and by making these small adjustments we are able to ensure no water is wasted and we hit our mark constantly. It’s the same as an Air Conditioner making adjustments in order to achieve the desired temperature and there are many different ways to help visualise how a MPPT works.
Aside from the integration of 4 MPPT the new range comes with a few extra features that further increase its appeal. It features a robust wireless Wi-Fi configuration that means they can create their own network should there not be one on site. It supports bi-directional cloud communication and remote diagnosis. This means issues can be determined without the need for a primary inspection, saving time.
Another great aspect is the fact that firmware updates can be delivered wirelessly or OTA (Over The Air). No need for USB drives anymore! All of these improvements make the inverter easier to use and any issue can be resolved with minimal fuss which we feel is incredibly important to our end users. The install is made easier by the inverter having rear cable entries which is a plus for us and it has a built-in AFCI.
All of these features plus IP 65 protection makes the H8E and H10E stand above the rest when it comes to solar inverters and the units have generated quite a bit of excitement amongst those in the industry. Flexibility is key and the ability to add more strings either on install or down the track as system owners want to expand due to so many MPPT is big news. You can take a look at the data sheet for these inverters by clicking here.
When all factors are bought together with the fact the inverter has an EU efficiency of 97.3% we can’t help but applaud Delta for finding even more ways to improve their already impressive lineup of solar components. They are already established as an incredibly reliable brand that has been well received by Australian consumers and this dedication towards innovation is the hallmark of a company that is here for the long haul.
If you would like to know more about the range of Delta solar inverters we supply or would like to quote on a solar system including one please give us a call today on 1800 255 474 or head on over to our online quote form.
Our solar consultants are able to work with you to determine the best possible configuration so that you can get the right package for your rooftop and this experience combined with innovations as seen in the new Delta inverters means you will always be getting the most out of your new solar power system.
