Solar inverter - Solar kit - Inverter for home photovoltaic

Solar inverter - Solar kit - Inverter for home photovoltaic. Different types of PV inverters for home use. Is the difference realy that big? If you have the choice,  and it is not a photovoltaic modules kit, which one do you choose. The technical aspects or the brand? The best inverter for home use is perhaps the one that gives you the most information about your electricity production. Green installations have to match your need for electricity.

Solar inverter - Solar kit - Inverter for home photovoltaic

There are many types of DC inverters on the market. Often your budget is choosing for you, or the supplier is making the recommendation. When selecting a correct electrical PV converter, it is essential to take a closer look at the matter. Do not just go to the installer's choice. Start with your monthly electricity use. Know what your monthly power requirement is. Do you only have a one-year bill? Then request the monthly usage from the electricity supplier. A good guideline is your power requirement in a year and divided by twelve months.

If you live in a warm country such as Portugal. Especially in the Algarve, it is more efficient to know monthly usage. Heat from the sun heats the panels. The efficiency then goes down considerably. Practice proves that at de summer temperatures in the Algarve the energy production of the system can drop. Often as much as 50%. To get enough energy from your PV systems in these warm months. The total power of the string must be twice as high as your power consumption.

Solar inverter - Solar kit - Inverter for home photovoltaic

The power of an electrical converter must have the total capacity of the panels. On an installation with 2200 WP, a 2000 Watt can be enough. If the panels not ideally oriented to the south, sometimes a smaller one can still be purchased. Inverters are offered both with transformer and without a transformer. The transformerless generally have higher efficiency or less loss. They can recognise them as TL type, Transformerless. Today, most are transformerless.

If you suffer from a shadow, then it is essential to make a second loop of panels. In that loop are panels that have the shade. For that, you have to choose an PV inverter for home use with multiple trackers. A tracker optimises the power of a photovoltaic array. The characteristics of a electrical converter always state how many trackers it has. The electrical power of the panels will be determined by the weakest link in the array.

Another option is by choosing power optimisers are micro inverters. These are control units placed behind each panel, and each panel optimises individually.

Electrical converter are not entirely silent. The sound depends on the cooling. If there is a fan, you will hear the fan start and perhaps be running. In the specifications of the inverter, you can read how much noise is producing in decibels.

Solar inverter - Solar kit - Inverter for home photovoltaic

The monitoring of your PV systems always takes place via the inverter. Not all offer standard solutions for this. Here is an overview of possibilities:

  • Via Bluetooth:
    You can then read your converter with a program on a PC or tablet. This form is not ideal. The connection is often not powerful enough so that you usually have faults. Moreover, you can not read the inverter from the internet.
  • Via Ethernet:
    Your inverter connection via a network cable to your router. Then a connection is made with the servers of the manufacturer. Via an App or website, you can then view the performance of your panels from anywhere. This type of connection is practical and stable. However, not all manufacturers offer Ethernet. Sometimes an optional module has to be purchased.
  • Via Wifi:
    The same principle as via ethernet, but there is no network cable needed. An advantage over a cable connection via Ethernet, but this connection is of course slightly less stable. Also, a WiFi connection costs power. Not much, but always a bit.
  • Via a built-in web server (latest generation of converter):
    You can then connect to the electrical converter from your network, which you can then read out.

Solar inverter - Solar kit - Inverter for home photovoltaic

There are two difference string converters for use with PV kit installations. With an option to store in the inverter battery. These do not need the be AC powered to the grid. Or the grid tie inverters, who are in need of AC powered grid.

An solar inverter for home, are usually grid tie and/or string inverters. Basically, they are the same. A grid tie means that there is grid electrical power necessary or AC powered. If you suffer from power cuts, the grid tie inverters will not work when the power is off. A string converter with an option for a backup.

The inverter battery is the solution when power cuts occur. An battery for solar modules energy storage gives you the independence you want. Save the energy yourself for later so that you always have your own energy. An example is the Tesla Powerwall battery. This battery gives a household enough storage capacity to live fully or the grid. A modified sine wave inverter, transforms the DC power from the converter battery to AC power. All the modern inverter for home situations have this modified sine wave converter on board. But not all have the battery backup storage facility.

Solar inverter - Solar kit - Inverter for home photovoltaic

This picture is an example of a connection structure with a Victron Easy Solar,  All-in-one PV power solution. It is an ALL in ONE solution for regular power cuts, as we are experience often in the Algarve Portugal. Many other brands have the same solution and same quality. Like the SMA Sunny for example. The SMA Sunny is more targeting to particulars and Victron more to more significant photovoltaic array power systems.

Do you like to have more information about your power requirement with battery backup storage? Do not hesitate to contact me.
Any question?

And then there is the return aspect. A new one that you do not buy in a photovoltaic module kit is often more expensive. It is therefore essential to choose a renowned brand. A brand with a national or European dealer. The settlement of a guarantee usually goes better and smoother. If you need to replace your inverter. Generally, your type is available at a reasonable price.

Brands such as Victron power, SMA sunny, Fronius and Solar Edge have been on the market for years. These brands have proven themselves in the past and do so in the future. Remember that a technical device have to  last 10 to 25 years. Probably you pay a bit more than a cheaper alternative. But the return on your investment is in the future!

Last comment for the techies:

The name pure sine wave inverters come from the waveform of its output. They have pure sine waveform output is identical or replica as close as possible to general 50Hz mains. Modified sine wave is cheaper then pure sine wave inverters. As they do not require the complicated system to produce the output waveform. The only downside is that it introduces harmonic distortion to inductive and audio equipment.

Most electronic products are designed to be powered by mains. Pure sine wave is suitable for all applications. Delicate equipment like computers etc. like to have the pure sine wave converters. Washing machines etc., do not care so much about. A modified sine wave inverter will do in most cases.