Solar Hybrid System: comparison with grid-tied and standalone systems

Solar energy systems come in various configurations, and the choice is yours whether you go off the grid or stay on the grid. This article discusses the advantages of a Solar hybrid system, grid tied solar system and standalone solar systems (or Off-Grid solar systems).Each option has its advantages and disadvantages, and in this article discusses the  different options so you can make a well-educated choice.When making this choice, it is essential to understand your long term energy usage and your load profile. Before you research that, let’s go through the different types of solar systems.

Different types of solar systems

You have the following three choices:

1. Grid Tied System (also called On Grid or Utility Interactive System)
2. Off Grid System (also called a Stand Alone System)
3. Solar Hybrid System

What is a grid tied solar system?

As the name suggests, grid tied systems are always connected to the grid. The energy that your solar panels produce is fed to the grid.During times when there is no sunlight, your loads consume the grid’s electricity. In a grid tied system, there is no necessity for a battery to store electrical energy. Here the grid serves as the storage of your solar energy.

Advantages:

• As it does not require battery banks and other standalone components, it is relatively cheaper than Off-Grid or hybrid systems.
• It facilitates you to take advantage of net metering. Any extra electricity that you produce can be sold back to the utility. This means that by the end of the month, you only pay for the net kWH electricity used.

Disadvantages:

• Since you do not have a battery bank, you can’t store electricity. If during the night, your grid is down, you will not have any electricity.
• Utility companies charge monthly fees that you’ll need to pay.

Off grid solar systems

Off grid solar systems or standalone systems are not connected to the grid. The solar panels produce electricity, which is stored in the battery banks. During nights this electricity is used to provide power.This is the only alternative when you live in a remote area where there is no electricity and you do not have grid access.Standalone systems are also used in areas where the grid is present, however the power supply is unreliable.

Advantages

• Only option if you live in a remote area with no grid access
• Feeling of being self-sufficient for your energy demands is great.
• Grid failures and downtime won’t affect your power supply

Disadvantages:

• The additional costs of installing a battery bank, and in some cases an alternative source of power like a diesel generator, makes these systems more expensive than a grid tied system.
• Standalone systems have more components and therefore need more maintenance. Especially the batteries need regular care.
• Replacement of battery banks is another problem. Battery banks are designed to last for 7-10 years after which they need to be replaced. This is a cost that you need to take into account.

[caption id="attachment_4835" align="aligncenter" width="535"] Solar hybrid system: without AC input[/caption]

Solar hybrid systems

Hybrid solar systems can be called the best of both worlds. They are also referred to as off grid solar systems with an option of utility backup.One configuration of this system requires you to have a disconnect switch which you could toggle on or off depending upon your electricity requirements. Usually this is an automatic switch.

Advantages:

• You can switch between power from the grid or power from your battery bank at you own will.
• Less expensive than a complete stand alone system, as there is no need for a backup generator. The possibility to connect to the grid serves as the backup power.
• Availability of the grid means that you can likely downsize your battery bank capacity.
• Less maintenance and higher reliability IF the grid is reliable.

Disadvantages:

• Cannot be used in remote areas where there is no grid power.

On-grid, standalone or solar hybrid system, the choice is yours

After comparing the pros and cons of various solar power systems, you can decide which option serves your purposes and is the best for you!