Off-Grid Or Grid-Tie, Which Way Should I Go?
When most people consider installing a solar system, they are usually thinking about a system tied to the grid. This system, often called a grid-tied system, makes sense for most people.
In addition to helping to deal with climate change, Solar can increase the value of your home. Also, solar energy can significantly reduce or eliminate Electricity bills.
With a grid-tied system, there is a smaller initial investment, as the Solar system does not have to store energy, or meet all of the homes energy needs. When there is any excess power produced by the solar system, it is sent to the grid (Export). If the system does not produce enough power for the home, it can draw some from the grid (Import).
Besides a grid-tied system, you have the option to install a stand-alone system, called an off-grid system. While off-grid systems typically cost more (at least double), they are sometimes necessary, especially if you live in remote parts of New Zealand. For those close to the grid, the option between a grid-tied and an off-grid system is usually an easy one. Due to the cost of an off-grid system, most people would connect to the grid.
However, as with any consumer decision, it is important to have all the facts, so that you can make an informed decision. This guide will go into detail to show you the benefits and downsides of each type of solar system.
Grid-Tied Solar System
A grid-tied solar system is often the simplest and cheapest of all options available. With a grid-tied system, the local utility provides power when the solar panels cannot produce enough power for the home. For instance, at night or on cloudy days, power flows from the grid to the home.
Save Money on Your Monthly Electricity Bill
A grid tied system ensures that you can still access grid power, while reducing how much of it you need. As a result, you can significantly cut down your monthly power bill. The key factor in reducing the bill is the amount of solar energy you can self-consume. Since retailers pay little for solar power you export to the grid, and they charge you a lot for the power you buy from them, it makes sense to schedule your electricity consumption during the day when solar power is available, and avoid high loads at night.
It Costs Less Upfront
When comparing the costs with an Off Grid System, a Grid-Tied system costs significantly less upfront. One of the biggest costs of an off-grid system is the battery bank and the backup generator. In addition, an Off Grid System requires a larger Inverter and Solar Panel Array to meet all of the electrical needs. A grid-tied system eliminates the need for such a costly purchase.
The cost of labor for a grid-tied system is significantly less since it takes much less time and expertise to install it. Additionally, ongoing maintenance work is less when compared to an off-grid system. For instance, most quality battery banks need to be replaced every ten to fifteen years if well maintained.
Improve the Home’s Value
A grid-tied system can improve a home’s value, no matter where it is located in New Zealand. The reason for this is that buyers expect to pay less on their electricity bills, which makes them more willing to pay a premium. Additionally, international studies show that homes with a grid-tied system sell faster when compared to similar homes in the same area.
An Off-Grid or standalone system is the alternative to a grid-tied system. As the name implies, this system is not connected to the grid. It is a great solution for those who are too far away from the grid, or for those who simply want independence from the grid.
An off-grid system is more complex and comes with a higher upfront cost than a grid-tied system. With an off-grid system, one needs to include power storage in the form of a battery bank and a backup generator. Power storage is needed since there is no grid to provide power when the sun sets. The battery will store the extra electricity for use when needed (usually at nights and overcast days).
While a Off Grid system can cost thousands more than a grid-tied system, it can make financial sense depending on how far away you are from the grid. For instance, if you are located in difficult terrain which is far from the grid, using an Off Grid system can cost less than a grid-tied system. In remote areas the cost of connection to the grid can be very high or sometimes prohibitive.
Cheapest Option in Remote Areas
For those in remote areas, using an off-grid system makes more financial sense than trying to install power from the grid. Even when you are relatively close to the grid, the cost of connecting can still be significantly higher in a rural setting than in an urban area. If you are quoted more than $10,000 for connecting to the grid it may make sense to consider going off-grid.
An off-grid system, if designed and installed well, can give you the peace of mind you need when it comes to your energy needs. For some people, this feeling extends beyond simply saving money, although that is an important reason. One benefit of an off-grid system is that your household does not need to come to a standstill every time the grid goes down due to power line failure. Besides that, it ensures you are insulated from fluctuations in power prices, which can allow you to manage your budget better. Also, when there is a major disaster or storm damage, you will most likely have power available when the grid is down.
No Power Bills
You become your own Power Company when you have an Off Grid system and you don’t have any Lines charges or Power Bills. However, you do need to consider maintenance costs, and budget for replacement batteries every 10-15 years typically for well maintained good quality batteries.
Hybrid Grid-Tied System with Batteries
While the two primary options are an off-grid system and a grid-tied system, there is a third option known as a Hybrid grid-tied system with batteries. This system can be split into two subcategories as follows; 1) A grid-tied system without back up, with batteries only used to store surplus solar energy for use when needed, and 2) A grid-tied system with backup batteries to an essential load switchboard.
For the option with battery power storage only, it is a great option to control when the homeowner purchases power. For instance, power companies sometimes have time-dependent tariffs. Power is expensive at peaks, usually in the morning and at nights (when sun power is limited or not available). Such a system ensures the homeowner uses as much solar power as possible without having to rely on costly grid power. Doing so will help you to maximize usage of your solar power.
The second option, where the Solar system and batteries are used as a backup power source costs slightly more, because you will have to rewire your house’s switchboard, and separate essential load circuit from other circuits. However, it gives people the option to have electricity for essential needs when the grid goes down, as is common in some regions of the country. Please mind that the power will be available only to essential appliances, most likely lights, refrigeration, water pump, and anything else you consider as essential.
One of the benefits of a hybrid system is that the upfront cost is often lower compared to a full off-grid system. However, it still costs more than a pure grid-tied system because a battery bank and a more advanced Hybrid Inverter is being installed.
Whether you opt for a hybrid, off-grid, or grid-tied system, you will still get to enjoy the benefits of using solar power. If you are connected to the grid, we highly recommend benefiting from it and installing a grid-tie system or a hybrid one. Going off grid is costly and not necessary if you have easy access to the grid, yet in some cases it is the only way to go.
If you would like to benefit from the access to power from the grid but at the same time you care about the resilience of the supply, than the best option is a hybrid system with essential load circuits.