Comparing And Selecting Solar Panel And Battery Packages - Making Sense Of Your Options

Posted by
Alex
Jun 08, 2017

Using solar and battery systems to reduce your dependence on the grid makes a lot of sense, but all the technical jargon isn’t always so easy to understand. Don’t worry, this article will get you up to speed on the differences between hybrid vs stand-alone systems, monocrystalline vs polycrystalline panels, total capacity vs usable capacity, and more. Most importantly, we’ll give you the tools to evaluate these choices based on your specific needs.

You already know that solar panels and batteries can help you save big on your home electric bills. You know that, once you choose your solar package, you're taking control of your energy future and breaking the chains that keep you tied to profit-hungry utility providers.

But where do you start? When solar technology starts to sound like a foreign language, how can you choose the panels and battery options that are right for you?

Below, we'll break down some of the most common words, phrases and concepts you'll hear as you begin your solar journey so that you'll walk away educated on how to navigate this new language. You'll know the key words and phrases - and you'll know what you're after and what you're not.

And if - after all that - you still have questions, our Solar Mentors can help.

Understanding the Three Types of Solar Energy Systems

One of the first choices you'll have to make as a new solar consumer is the type of system you'll install. Generally, you have three options: panels-only solar systems, hybrid solar + battery systems, and off-grid systems.

Panels-Only Solar Systems - Panels-only systems only generate solar energy during the day, when the sun's out. Because of this, they'll offset about half of your electricity bill.

Hybrid Solar + Battery Systems - Hybrid systems, which incorporate panels, batteries and a hybrid inverter, can reduce your electricity bill up to 90% by storing solar energy captured through the panels in the batteries, enabling you to power your home day and night. They're still connected to mains power, and if there's a blackout, many systems allow you to use your batteries to keep your lights on and your food fresh.

Stand-Alone Off-Grid Systems - These systems let you become completely energy self-sufficient and never have an electricity bill again. Off-grid systems use similar equipment as hybrid solar + battery systems. But because they don't have mains electricity available as a back-up, most homes using them add a generator for the few days a year the solar batteries need a top-up. At that point, a generator can kick in and power your home for a few hours.

Notes on the Solar Selection Process

Thanks to the descriptions above, you may already have some idea about which solar system will best suit your needs. If you remain on the fence, however, consider the following factors:

Government rebates exist that will help offset the costs of your solar installation. For every new panel you install, you get more rebates. And since the rebates basically cover the cost of the panels, you're essentially getting free panels - so get all the free panels you want!

Your solar system can evolve over time. If you choose, you can start with a panels-only system and later incorporate batteries to create a hybrid system. If you imagine going down this road, however, make sure to include a hybrid inverter from the start to make adding batteries easier in the future.

Be wary of systems labeled as "battery ready." Often, these are simply panels-only systems that will require the later installation of a hybrid inverter or equivalent technology to be able to add batteries. Not only will you save money overall by installing a hybrid inverter with your original system, but your system will run more efficiently as well.

Though there are clearly pros and cons to each option, many ShineHub customers choose hybrid solar + battery systems due to their ability to generate energy day and night, while still allowing access to grid energy as a backup.

Sound good? Now that you've been educated about the process, let's get into the specific solar package options you have in front of you.

Hybrid Solar + Battery Product Package Options

Because every home and family is different, every solar solution must be customisable as well. So while every hybrid solar system consists of panels, batteries and a hybrid inverter, the number, size, capacity and brand of these elements varies based on the package chosen.

Don't concern yourself with part numbers and other specifications just yet. Instead, ask yourself the following questions as you explore different product packages:

What appliances will you run? Some solar energy batteries are designed to power small things: your TV, your lights, etc. Others are meant to handle more energy-intensive appliances, like washers, dryers and air cons.

Will you need to access your solar energy during a blackout? If you'll need to be able to use your solar and battery system to power your home at these times, make sure your hybrid inverter comes with blackout protection, and that your installer is trained to configure this type of installation. Not all are.

Where will you place your batteries? Options exist that will let you install your batteries indoors or outdoors, either on a wall or on the ground. These batteries can be quite heavy, weighing at least 100 kilos. If you'll be installing them on a wall, your wall must be strong enough to support them. If you'll be placing them on the ground, plan for an inverter and battery package that will be roughly the size of a tall washing machine. If you'll be installing on the wall, your setup might look something like this:

Will you want to go fully off-grid in the future? If there's a possibility you'll detach from mains electricity at some point, look for a hybrid inverter that's also designed to support off-grid operation.

Planning ahead saves you money; as you can imagine, installing an inverter that won't work with batteries or off-the-grid can become quite costly if you want to make the move away from grid energy down the road. Asking these questions and speaking with a Solar Mentor will help you come up with the right solar approach, based on your unique needs.

Selecting Your Batteries

Hybrid solar + battery package options can seem overwhelming, but we'll make it easy for you when it comes to the batteries. There are really only four substantial differences in batteries, so skip the marketing hype and take these factors alone into account:

Total Capacity - Total capacity is somewhat self-explanatory: it's the total electricity your batteries can store. Measured in kWh, a battery for low-energy users will have a capacity around 5 kWh, while a large one runs around 13 kWh.

Usable Capacity - Of your battery's total capacity, only a fraction is considered usable energy. Old battery technology has a usable capacity around 30%, while more modern Lithium Ion batteries can run closer to 90-100%.

Battery Lifecycle - Every battery is rated for a certain number of cycles that constitutes its lifespan. A cycle is like a charge on your iPhone - 1 charge is 1 cycle. Most homes use one battery cycle per day, while most batteries are rated between 2,000 and 10,000 cycles which means that they're tested to last between 5 and 25 years.

Continuous Flow Rate - Flow rate refers to the amount of power you can pull from your batteries at any given time. If you want to run big appliances like washers, dryers, air cons or water pumps, you'll need a battery with a high enough continuous flow rating to support the necessary power draw.

Most of this information can be found on the battery datasheets available on manufacturers' websites. If you can't find them, don't bother sifting through the mess on Google because a lot of the time you'll get a brochure for the version of the product that's available in Europe or America! Just email info@shinehub.com.au, and we'll send you any brochure you want.

Comparing Your Panel Options

Though your options here may seem confusing, most homeowners will wind up choosing between two options: monocrystalline and polycrystalline solar cells.

Monocrystalline Silicon Solar Cells

Monocrystalline solar panels have some of the highest efficiency rates and space-efficient designs on the market. Because they're made of the highest-grade silicon currently available, their efficiency rates typically fall between 15-20%, and they can generate higher power amounts in a smaller amount of space.

Monocrystalline panels are, therefore, a good option if you have limited roof space. You may also hear that they also perform better in low-light conditions than polycrystalline solar panels with similar ratings, and while that's true, the actual difference is negligible.

Because monocrystalline panels are one of the most expensive options available, they're really only worth it if you can't fit many panels on your roof and you want the extra power.

Polycrystalline Silicon Solar Cells

Polycrystalline silicon solar panels are the "sweet spot" when it comes to solar performance and value. They cost less than their monocrystalline counterparts, but good quality poly panels produce very similar amounts of energy.

It didn't used to be this way, but these days, you'll only need an extra panel or two to equal the performance of monocrystalline panels.

Building-Integrated Photovoltaics (BIPVs)

If you have the extra cash and want to integrate your solar cells into the rest of your home, building-integrated photovoltaics - cells that are built into facades, roofs, windows, walls and other features - can give you the minimal look you desire.

That said, be aware that this technology is still very new - and very expensive. If you're already re-roofing, BIPVs may be worth considering. Know, however, that they'll come at a substantial cost, and they haven't been proven as reliable as the monocrystalline or polycrystalline panels described above.

Thin-Film Solar Cells

Finally, you may hear thin-film solar cells being discussed, but as of this writing, they aren't a commercially viable option for residential applications. Although thin-film technology makes it possible to produce a lot of panels at a very cheap cost, you still need four times the number of panels to generate the same power as a monocrystalline or polycrystalline equivalent - and their warranties are much shorter.

While we're always hoping new technologies will drive down the cost of solar panels, thin-film solar cells are only ever going to be a good fit for commercial applications. For personal use, you're better off sticking with tried-and-true silicon cells.

Choosing Your Solar System

Hopefully, this quick primer has armed you with the knowledge needed to make an educated decision for your solar future.

If you still have questions, we're here to help. Our Certified Solar Mentors can help you select the right system for your needs and get multiple quotes for your home to consider. Use our online form to book a totally free, no-hassle call today.

About the Author

Alex 1 followers

Alex is a home energy expert with experience across virtually every area of the industry, ranging from energy efficiency and smart home gear to the latest solar and battery technologies. As co-founder of ShineHub, he is responsible for delivering the best digital experience in the industry for customers as well as managing customer-facing communications.

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