Battery Backup Systems November 13th, 2024 Have you noticed more solar panels popping up on roofs around Nelson? Maybe you’ve been considering them yourself. But there’s often a question that comes up: “What about when the sun’s not shining?” It’s a fair point. After all, we still need power at night and on cloudy days. That’s where battery backup systems come in, and they’re becoming an increasingly common sight in homes across New Zealand. We’ve been installing solar systems since 2006, and we’ve seen a lot of changes in that time. One of the biggest has been in battery technology. These systems used to be bulky, expensive, and a bit of a hassle. But that’s not the case anymore. If you’re curious about how modern battery systems might fit into your home or business, you’ve come to the right place. We’ll walk you through the basics, explain who can benefit, and give you the information you need to decide if it’s right for you. No fuss, no exaggeration – just straight talk about powering your property. What exactly is a battery backup system? A battery backup system is a smart addition to your grid-tie solar setup. It’s like having a big rechargeable battery for your whole property. During the day, when your solar panels are working hard, this system stores up extra energy. Then, when the sun goes down, it releases that stored power, keeping your lights on and your fridge running. Here’s why our customers love their battery backups: Your solar keeps working even when the power’s out You’re not at the mercy of rising power prices You use more of the solar energy you produce Who can benefit from a battery backup system? Now, you might think these systems are just for folks with solar panels, but that’s not the case. We’ve installed them for: Homes with grid-tie power systems (solar, wind, or hydro) Regular homes and businesses wanting a bit of peace of mind Clever people looking to make the most of off-peak power rates Whether you’re in sunny Nelson, coastal Marlborough, or tucked away in Golden Bay, a battery backup can make a real difference. How do you pick the right size battery backup? Choosing the right size isn’t too tricky, but there are a few things to consider: What to think about Why it matters Your budget How much you can invest now vs. save later How much power you use Your daily habits make a difference What you want it to do How long do you need it to last in a power cut? A well-designed system won’t drain your batteries too much, which means they’ll last longer. Pop in for a chat, and we’ll help you figure out what’s best for your place. What kind of batteries are we talking about? Battery technology has come a long way in recent years, and we’ve kept pace with these changes. At Current Generation, we’re always looking for the best solutions for our customers across the Top of the South. Lithium batteries: The new standard These have become our go-to choice for most installations They last longer, charge faster, and take up less space Perfect for homes and businesses alike Lead-acid batteries: Still an option We still install these in certain situations They’ve been reliable workhorses for years Sometimes they’re the right fit, but it’s less common now Why we choose BYD batteries We’ve done our homework, and that’s why we exclusively stock BYD batteries. You might know BYD as the world’s largest EV maker, but their energy storage solutions are top-notch too. Here’s why we trust BYD: Flexibility: Their modular design fits any setup, from small homes to large businesses Capacity range: From 2.56kWh to a whopping 983kWh Safety first: They use lithium iron phosphate chemistry, which is safer and more ethical Long-lasting: Comes with a solid 10-year warranty Can you keep an eye on how it’s working? Absolutely. The systems we install have some nifty monitoring tools: You can check how it’s doing from anywhere with internet There are apps for your phone or computer You’ll see exactly how much power you’re making and using Whether you’re at home in Nelson or Blenheim, or away in the Marlborough Sounds, you’ll always know how your system’s performing. Why bother with batteries when you could just get a generator? Good question. Batteries have some advantages over generators: They’re quiet: No noisy engine kicking in during a power cut They use your solar power: Makes the most of what your panels produce They can save you money: Unlike generators, which cost money to run How does it work in the real world? Let me show you some data from a system we installed in Richmond: Their batteries were full by lunchtime, using only about 20% overnight You can see the solar panels working hard all day They only used 7 cents worth of power from the grid in 24 hours Any extra power goes into the batteries before being sent back to the grid The system makes sure the house and batteries are taken care of first Here are some screenshots of the monitoring from a GTBB (Grid Tie Battery Back-up): Battery SOC (State of Charge): The batteries were fully charged about lunchtime and were discharged by about 20% overnight. Battery Performance: The battery voltage (blue) climbed during the morning (the dips are when the sun is behind a cloud, or when a large load is drawn). During the afternoon it stayed steady (float charge). At sunset, the bank is no longer being charged and the battery bank’s voltage drops and goes down slowly overnight. The ‘blips’ overnight will be the fridge compressor turning on and off. Consumption: During the day, the house is running mainly from solar with minimal draw from the batteries or grid. Only ¼ of a kWh was taken from the grid for the whole 24 hour period ($0.07 worth). Solar Yield: This shows how energy is sent to the batteries until they’re full and then exported to the grid after that. During the winter months, there would be far less energy exported. Ideally, the grid is only really used for back-up and most of the energy used is produced on-site. Live Feed: This is the live feed from the same system the following morning. The energy being yielded is not being exported to the grid – it gets sent straight to the batteries and the home until the batteries are full. When this snapshot was taken, 223W was being sent to the batteries. Is it worth putting your hard-earned money into? With these advancements in battery technology, there’s never been a better time to consider adding storage to your solar setup. Here’s why our customers across the Top of the South are making the switch: Energy independence: Use your own solar power day and night Backup power: Keep the lights on during those pesky power cuts Future-proofing: As power prices rise, you’re in control Look, we know it’s an investment. But with battery prices coming down and technology improving, many of our customers find it’s worth every penny. We’ve been in this game since 2006, and we’ve seen the industry grow and change. Our focus has always been on providing top-notch solutions for the Top of the South Te Tau Ihu region – from the West Coast to Golden Bay, Nelson to the Marlborough Sounds, and over to sunny Blenheim. But we’ve got experience all over New Zealand too. We’re not just about selling you a system – we’re about finding the right solution for your needs. Our designs are customised to your site, maximising your resources and giving you the best value for money (which isn’t always the cheapest option!). We make sure it works first time and looks great to boot. If you’re curious about how these new batteries might work for your place, why not give us a call or stop by our shop? We’ve been helping folks around the Top of the South with their power needs for years now, and we’d be happy to share our local knowledge and experience with you. Always straight talking, we’ll give you the facts, tools and support to understand the solutions we think are appropriate for you, allowing you to make an informed decision about how you power your future! Original article: BATTERY BACKUP SYSTEMS ADD VALUE TO YOUR GRID-TIE SYSTEMA battery back-up system adds two levels of functionality to a grid-tie solar system: A battery back-up system from Current Generation will charge during the day and then release the stored energy overnight, with no disruption of power supply to the home. Energy will only be ‘imported’ from the national grid if it is necessary, and less energy imported from the grid means a lower power bill. This also protects the consumer from rising electricity prices. · In the event of a power cut, the solar array will continue to work without any disruption of power supply to the home. As long as the batteries are being sufficiently topped up each day with solar energy, the power cut will not affect the home.ANY HOME CAN BENEFIT Battery back-up systems are ideal for adding value to a grid-tie power system (solar, wind or hydro power), however they can also be used in a normal home or business without a renewable energy system for emergency back-up, and/or to maximise benefits from off-peak electricity rates. WHAT SIZE DO I NEED? The best size depends on the budget and the energy consumption of the home, and what the consumer’s expectations are. A well designed system will minimise the ‘depth-of-discharge’ of the batteries, which in turn increases their service life. A decent battery bank is a significant investment, so it is important to get it right the first time. A medium sized lead-acid battery bank for a normal home fits in a battery box which is about half the size of a standard chest freezer. Lithium-ion batteries are smaller and lighter than lead-acid batteries, however their use in renewable energy systems is still an emerging technology.MONITORING Extensive monitoring systems are available, which put the consumer in charge of their power system. Real-time information can be accessed from anywhere in the world via the internet, and apps are available for smart phones and computers.A battery back-up system is the only sensible way to provide back-up and to allow your PV system to remain active during a power cut. There is another incentive to installing a battery back-up system – the ‘self-consumption’ of the energy your PV system generates increases dramatically. This adds value in a way that a generator can’t (because running a generator will never save you money).To explain what I’m talking about, here are some screenshots of the monitoring from a GTBB (Grid Tie Battery Back-up) we recently installed: The batteries were fully charged about lunchtime, and were discharged by about 20% overnight. The battery voltage (blue) climbed during the morning (the dips are when the sun is behind a cloud, or when a large load is drawn). During the afternoon it stayed steady (float charge). At sunset, the bank is no longer being charged and the battery bank’s voltage drops, and goes down slowly overnight. The ‘blips’ overnight will be the fridge compressor turning on and off. During the day, the house is running mainly from solar with minimal draw from the batteries or grid. Only ¼ of a kWh was taken from the grid for the whole 24 hour period ($0.07 worth). This shows how energy is sent to the batteries until they’re full and then exported to the grid after that. During the winter months, there would be far less energy exported. Ideally, the grid is only really used for back-up and most of the energy used is produced on-site. This is the live feed from the same system the following morning. The energy being yielded is not being exported to the grid – it gets sent straight to the batteries and the home until the batteries are full. When this snapshot was taken, 223W was being sent to the batteries. So, the system works very well and adds multiple layers of functionality to a grid-tie system. As very few units are being imported (bought from the retailer), the money saved offsets the cost of the batteries over time. In the event of a power cut, the system remains active. It might be necessary (depending on the power use at your property) to have certain circuits switch off during a power cut to prevent over-discharge of the batteries, but this is fairly easy to automate. It can also be done manually of course. A generator can also be added if you need to be able to run large loads during extended power cuts. The battery bank needs to be sized based on one’s consumption and PV yield. If a battery bank that is too small is used, the voltage will drop too much when large loads turn on, causing importing of energy from the grid. This can also shorten the battery life. Furthermore, if a large load is switched off while in ‘off-grid mode’, a sudden in-rush of current from the PV to the batteries can happen, which is not ideal. A large battery bank is better for the batteries, but a balance needs to be struck between the service life of the batteries, their performance, and the capital investment. In my opinion, a battery back-up system is the best way to add value to a grid-tie solar system. It will cost more up-front, but this will even out over time, all the while giving you added functionality.
