Inverters for grid tie homes & businesses in Europe

Energy independence? What is a hybrid inverter?

Energy independence is a term used to describe the ability of a home to generate and use its electricity, independent of the electricity grid. With the increasing popularity of renewable energy sources such as solar panels, energy independence has become a feasible option for many homeowners. Hybrid inverters are an essential component of a solar power system, enabling energy independence and reducing dependency on traditional sources of energy.

A hybrid inverter is an inverter that combines the functionality of a grid-tied inverter with a battery inverter, allowing energy to be stored in batteries for use when needed. Hybrid inverters enable homeowners to use their solar panels to generate electricity during the day and store excess energy in batteries for use at night or during times of high electricity demand.

Energy independence with a hybrid inverter offers several advantages:

1. Reduced Electricity Bills: By generating and storing their electricity, homeowners can significantly reduce their dependence on the electricity grid and save money on electricity bills.
2. Increased Resilience: In the event of power outages or disruptions in the electricity grid, homes with a hybrid inverter can continue to generate and use electricity, providing increased resilience and peace of mind.
3. Environmental Benefits: By using renewable energy sources such as solar panels and storing excess energy in batteries, homeowners can reduce their carbon footprint and contribute to a cleaner, more sustainable future.

When considering energy independence with a hybrid inverter, there are several factors to consider:

1. Battery Size: The size of the battery bank will depend on the amount of energy required and the energy needs of the home. A larger battery bank will enable more energy storage and greater independence from the electricity grid.
2. Installation and Maintenance: Hybrid inverters require professional installation and maintenance to ensure optimal performance and safety. Homeowners should work with a professional installer who can advise on the best system for their home and provide ongoing support and maintenance.
3. Available Resources: Homes with access to ample sunlight will generate more energy from solar panels and be better equipped to achieve energy independence. However, even homes with less sunlight can still benefit from a hybrid inverter system.

Some popular hybrid inverter manufacturers in Europe include SMA, Victron Energy, and Fronius. When selecting a hybrid inverter, it is important to choose a reputable manufacturer that offers a warranty of at least five years.

In conclusion, hybrid inverters enable homeowners to achieve energy independence, reducing dependency on traditional sources of energy and providing several advantages, including reduced electricity bills, increased resilience, and environmental benefits. When considering energy independence with a hybrid inverter, homeowners should consider factors such as battery size, installation and maintenance, and available resources. By working with a professional installer, homeowners can ensure that their hybrid inverter system is correctly installed and optimized for optimal performance and efficiency.

Just Installed 4000W of solar system on my roof with 500W solar panels. What grid-tied inverter should I choose for my home?

Congratulations on your new solar system! Choosing the right grid-tied inverter is crucial to ensure that your solar system operates at optimal efficiency and provides maximum energy output. In your case, with a 4000W solar system and 500W solar panels, you will need an inverter that can handle a DC input power of at least 4000W.

There are three types of grid-tied inverters to consider: string inverters, microinverters, and power optimizers. Let’s take a look at each of these types of inverters and their pros and cons to help you make an informed decision.

1. String Inverters:

String inverters are the most common type of inverter used in solar systems. They are installed on the wall near the main electrical panel and convert the DC power from the solar panels into AC power that can be used in your home or fed back into the grid. String inverters are the most cost-effective option for larger solar systems like yours.

Pros:

• Cost-effective
• Simple design and installation
• Easy to maintain and repair

Cons:

• Performance can be affected by shading or mismatched panels
• Single point of failure (if the inverter fails, the entire system shuts down)
• Limited monitoring capabilities

For your solar system, a string inverter with a DC input power rating of at least 4000W should be sufficient. Some popular brands of string inverters include SMA, Fronius, and Ginlong Solis. At a normal string inverter When one panel in the string suffers reduced output, every panel in the string drops to that reduced output. For example, you may have 330W panels, but if a single panel in the string falls to 250W production, every panel in that string is going to produce 250W of power.

Here are some factors that can cause this drop in production:

• Shade. Your panel will produce less energy when it’s shaded, and shading on one panel will impact the entire string.

• Panel Facing. Panels produce the most energy when they face directly at the sun. In the EU, UK or the US, panels should face south for optimal production. If you split a string of panels on your roof so that half face south and half face east, the south-facing panels will drop to the lower output of the panels that face to the east.

• Equipment Malfunction. If one of your panels stops working, your entire string stops working until you repair or replace the defective panel.

For these reasons, we only recommend using string inverters vs. micro-inverters or optimizers if your system will receive full sunlight year-round and all panels will face the same direction. This tends to work best when you have lots of space on your property and can build a fixed ground mount clear of any obstacles. Assuming you meet these conditions, string inverters are a fantastic option to help you save some money on your solar project.

2. Microinverters:

Microinverters are small inverters that are installed directly on each solar panel. They convert the DC power from each panel into AC power, which is then combined and sent to the main electrical panel. Microinverters are a good option if your solar panels are installed in areas that are prone to shading or if you have mismatched panels.

Pros:

• Performance is not affected by shading or mismatched panels
• Better monitoring capabilities than string inverters
• Each panel operates independently, so there is no single point of failure

Let’s say you live in the average American household, which uses roughly 900 kilowatt-hours of electricity per month. What if you want to go solar, but only have the budget to offset a smaller portion of that usage upfront?

With an initial budget of 2,000, you could start with five Enphase IQ7+ micro-inverters paired with five JA Solar 335W panels. That would allow you to offset about 25% of that energy usage. When choosing between a micro-inverter vs. central string inverter, keep in mind that you’ll start saving money immediately, since solar is cheaper than buying power from the utility, and you’ll be negating a portion of your bill. Later down the line, you can scale the system up to offset 100% of your household energy usage.

Cons:

• More expensive than string inverters
• Installation can be more complex and time-consuming
• Maintenance and repairs can be more difficult as the inverters are located on the roof

The trade-off for the convenience of using a micro-inverter vs. string inverter is that micro-inverters are the most expensive option on a cost-per-watt basis. Once you scale into larger-scale systems, string inverters (with or without optimizers) are more cost-effective than micro-inverter systems. Once you eclipse a certain system size (say 6-8 full-sized panels), we typically recommend switching over to a string inverter design as it will be the most cost-effective option.

3. Solar Panel Power Optimizers:

Power optimizers are similar to microinverters in that they are installed on each solar panel. However, instead of converting DC power to AC power, they optimize the DC power output from each panel before it is sent to a central inverter. Power optimizers are a good option if your solar panels are installed in areas that are prone to shading or if you have mismatched panels.

Pros:

• Performance is not affected by shading or mismatched panels
• Better monitoring capabilities than string inverters
• Each panel operates independently, so there is no single point of failure

Cons:

• More expensive than string inverters
• Installation can be more complex and time-consuming
• Maintenance and repairs can be more difficult as the optimizers are located on the roof

Of course, the trade-off is the additional functionality comes at a higher cost. A SolarEdge HD-Wave inverter with optimizers costs roughly twice as much per watt as the SMA Sunny Boy string inverter. But you should keep in mind these cost-per-watt figures assume each panel is working at max efficiency. If you build a string inverter in a shaded location and don’t put optimizers on your panels, your system will never produce at its rated output.

In conclusion, for your 4000W solar system with 500W solar panels, a string inverter with a DC input power rating of at least 4000W should be sufficient. However, if your solar panels are installed in areas that are prone to shading or if you have mismatched panels, a microinverter or power optimizer may be a better option. When selecting an inverter, it is important to choose a reputable manufacturer and work with a professional installer who can advise on the best system for your specific needs.

What inverter to install in my home? Single or three phase?

The decision to install a single-phase or three-phase inverter in your home will depend on a few factors such as the size of your home, the number of appliances, and your electricity usage.

Here are some things to consider:

1. Electricity Consumption: If you have a large home with high electricity consumption, a three-phase inverter might be a better option. This is because a three-phase system can handle higher loads and is more efficient at distributing power. A single-phase system is typically sufficient for small to medium-sized homes with moderate electricity consumption.
2. Available Grid Connection: In some areas, three-phase grid connection may not be available, so you will have no choice but to use a single-phase inverter. It is important to check with your local electricity provider to see what options are available to you.
3. Cost: A three-phase inverter is generally more expensive than a single-phase inverter. If you are on a tight budget, a single-phase inverter may be the best option.
4. Future Expansion: If you plan to add more solar panels or increase your electricity usage in the future, a three-phase inverter may be a better choice. It will provide more flexibility and capacity to handle higher loads.

Ultimately, the decision to install a single-phase or three-phase inverter will depend on your specific needs and circumstances. It is important to consult with a professional installer to determine the best option for your home and ensure that the installation is done safely and correctly.