5 Mistakes to Avoid When Designing your Solar System

5 Mistakes to Avoid When Designing your Solar System

If you're not well versed in solar, it can become complex and confusing pretty quickly, so it's easy get started down the wrong path without realising it. To help prevent any costly headaches, we want to share a few common mistakes people can make when they start to research and design their solar power systems, and how to avoid them.

If you're not well versed in solar, it can become complex and confusing pretty quickly, so it's easy get started down the wrong path without realising it. To help prevent any costly headaches, we want to share a few common mistakes people can make when they start to research and design their solar power systems, and how to avoid them.

1. Confusing Grid-Tied and Off-Grid Solar

    Solar power systems can be set up in two ways, grid-tied and off-grid.

    Grid-tied solar is what you will most commonly see in the suburbs, where there is easy access to the main power grid. The system is typically: solar panels producing power for the household, with any excess going back into the grid, and any deficit made up with power drawn from the grid.

    Off-grid solar is more common rurally, where no grid access is available for energy storage or top-up, so the system also includes batteries to store the energy produced by the solar panels, with any deficit able to be made up with a generator, or off-set by alternate means such as LPG. If you're wanting to feed back into the grid or not have batteries, you're not going to be off-grid.

    It’s important to note that saving money on your power bill and being off grid are very different things that don't go together. GridFree deals in off-grid solar, so if you're looking to get power where the grid either isn't available or is costly to connect, we can help.

    2. Building a Frankenstein system

    “I have an inverter off TradeMe and some panels from a few years back, can you help me build the rest of the system?” Unfortunately, the answer is usually no.

    A fair number of people will acquire their components slowly over time, holding out for deals until they’ve got everything they need to build a piecemeal system. Unfortunately, it’s not enough to have all the parts for a solar power system, they need to be compatible with each other to avoid problems like:

    • Undersized charge controllers for your panel output
    • Panels that are different sizes and can’t fit on the same mount
    • Components that are designed for different voltages/amperages and physically can’t be wired together
    • A system lacking essential components like circuit breakers
    • A system that no one is willing to support because it’s so piecemeal – it’s always the other manufacturer to blame!

    It’s not impossible to build a system up piece by piece, but unless you have (and stick to) a rock-solid plan, there’s no guarantee the components will ever work together, and all those savings disappear.

    This is why we designed our kits – so you don’t have to worry about this issue, because all the components are matched already. If you're looking to piecemeal the system because you can't afford it all at once, let us know and we can help, whether you put down a deposit or get third party finance.

    3. Improper system sizing

    If you’re new to off-grid solar, you might be looking at your power bill and trying to match that usage with solar panel output. But there are a few factors you need to consider before committing; such as sun hours, alternative energy sources, and power conservation.

    Lots of solar companies will quote a system based on allowing you to run everything you need even on the worst winter days, including high load items such as electric ovens or heating, resulting in an incredibly expensive and excessively large system. A simple change in your habits to conserve energy for just a few days, and switching high load usage to alternative energies such as LPG or woodburning can mean thousands of dollars in savings.

    To learn more about pricing and sizing a system, read our blog “Why Off Grid Solar Quotes are So High (and Why They Don’t Need to Be.)" 

    4. Not planning ahead

    When you start planning your system, it’s important to plan not only for your current needs, but how your needs might change over the next few years. Things like kids, new hobbies, and new appliances can all increase your energy consumption, so it’s important to think about future proofing your system.

    Some things to consider:

    Will you have room for expansion if necessary? If your system takes up your whole roof, where will you put your extra panels? Is there space for more batteries?

    Is your system designed to be expandable? Expanding a solar power system is not as simple as just adding on another panel or battery when you need it - your charge controller and inverter need to be sized to match your solar array and battery bank, and batteries will need to be added in sets of 2 or 4 for 24V and 48V systems respectively. If you think you may start with fewer panels and batteries, and expand in the future, you’ll want to opt for a charge controller and inverter that will match your future system, to save you the cost and hassle of replacing them later.

    Can your battery bank be expanded later? Depending on the battery type and age, it may not be possible to expand an existing battery bank. If you opt for lead-acid batteries, and decide to expand a few years down the line, the new batteries will take on the characteristics of the old ones, aging the new ones prematurely. Lithium batteries don’t face this issue due to an integrated circuit controlling the charge parameters, so the old and new batteries charge independently – they are significantly more expensive, however.

    5. Overpaying for installation

    In the same way that bigger solar companies may offer a very high quote for a solar system, they’re also more likely to charge a premium for the convenience of design and installation. This is especially true with companies geared towards bigger systems, who need to cover their high costs, and don’t want to deal with selling and installing small scale systems.

    What many people don’t know is that you can buy a packaged system and install it yourself, or bring on a local contractor to help with part of the installation. If you’re willing to take on organising the project and some of the tasks, working with a local electrician can save you a lot of money. You can save even more by doing it all yourself, as our kits are designed to be DIY-friendly (the exception being the hybrid inverter upgrade or wiring the inverter into your switchboard, which legally require an electrician to wire the 240V portions).

    If you're not keen on doing the electricals yourself, check out our list of installers here. They're familiar with GridFree kits and are happy to chat.


    These mistakes are why we started GridFree and created our kits – because we had to deal with minefield of not knowing what was best, not having any success with solar companies, and being forced to piecemeal a system ourselves. You can read more about that story here.

    We’ve done a lot of the hard work for you, by designing our kits and offering guides to how much you can run on them, however we also really prioritise our customer service. We encourage people to get in touch and ask us any questions they have, to ensure we can recommend the right solution. 

    Even though we don’t install the systems, we’re still responsible for designing them, and we want to sell systems that work. That’s why we take the time to get to know your needs, provide detailed instructions, and make time to help customers even after they’ve installed their kits. 

    So if you're ready to get started with solar, get in touch and we can help you find the right solution.