# How Home Solar Systems Work: A Beginner's Guide

## Метаданные

- **Канал:** SolarQuotes
- **YouTube:** https://www.youtube.com/watch?v=D7w3ZTecMYw
- **Источник:** https://ekstraktznaniy.ru/video/44152

## Транскрипт

### Segment 1 (00:00 - 05:00) []

Thinking about buying solar but feel overwhelmed? I'm Finn Peacock, a chartered electrical engineer. And if you're like me and you want to understand how all this solar stuff works before dropping thousands of dollars on it, this is the video for you. Let me start by showing you how solar panels work. And I've promised to keep it simple. At its heart, electricity is electrons moving in a circuit. But how does sunshine make electrons move in a solar panel? It's caused by something called the PV effect. Sunlight knocks electrons loose from the silicon in a solar cell and we capture that movement as DC electricity. Let's zoom in on a solar cell. It's a silicon wafer the size of a beer coaster and then it's chopped in half. See these faint lines across it? They're the metal fingers that collect the moving electrons. They feed them into those thicker vertical lines. They're called the bus bars. Think of it like tiny power highways collecting traffic from side streets. So that's in a nutshell how a solar panel works. — Now this is me in a nutshell. Help. I'm in a nutshell. How did I get into this nutshell? — But what about the rest of the system? A modern solar system is made up of five main parts. First up, your solar panels. These are the stars of the show. They turn sunlight into DC electricity using the PV effect that I just talked about. Down at ground level, there's your solar inverter. This is the brains of the operation. It takes the DC power from your panels and turns it into the 230 volts AC power that your home uses. Number three is a big switch next to your inverter. It's called an AC isolator and it cuts off the mains power from your inverter. Always turn this off first if you need to shut down your system. It's the safest way to do it. Your switchboard is the fourth part where everything connects. Your installer will install a circuit breaker for your new inverter here. And if the installer is not a cowboy, they'll also install a consumption meter. This little sucker measures the energy flows all over your house, so you can see how much energy your home is using, how much is being supplied from your solar, and the grid. If your switchboard is too small or not up to the current standard, you might need a new switchboard, and that's going to get expensive. It can set you back at least $1,200 or a lot more, depending. Finally, there's your grid meter. Your electricity company either installs a new one after your solar panels are installed or updates the software on your existing one to handle your new solar panels just like your old meter did. It still measures how much electricity you pull from the grid to charge you for it. But now you've got solar. It also tracks how much surplus solar you export back into the grid. So it knows how much to credit your bill. Just be aware that the credits you get for exporting solar will generally be small. Most of your solar savings will come from not using the grid electricity in the first place because you're using your solar instead. That's the basics. Now, let me clear up one of the most confusing things about solar. The difference between power and energy. Contrary to popular belief, power and energy are two different things. And even some people in the industry get this wrong. So, don't feel bad if it seems a bit confusing at first. Let me break it down in terms of solar panels. Power measured in kilowatts is all about speed. How fast all your panels can pump out electricity. When someone talks about a 13 kW solar system, they're talking about a solar system that produces electricity at a maximum rate of 13 kW. That's generally at midday on a perfect solar day. Power in kilowatt is the top speed of your solar system. Just like your car maker advertises the top speed of their cars, don't expect to hit it too often. Now, energy, that's measured in kilowatt hours. It's how much electricity you've made or used over time. Think of it like your car's odometer. When your bill says you've used 26 kW hours today, that's like saying you've driven 26 km. Just like you'll never hit the maximum speed of your car, you'll likely never hit the max power of your solar. A 13 kW system won't normally produce 13 kW of power for two main reasons. Firstly, most 13 kow systems actually use a 10 kow inverter. So, that's your speed limit right there. And you'll only hit peak power around midday on a nice day. Not too hot, not too cold. Goldilocks weather. Let me show you what I mean. Here's what a 13 kW system produced on a cracker of a day. See how it only hits 10 kW right at midday? It's been throttled by the max inverter power of 10 kW. And if you had a bigger inverter, you'd probably never hit 13 kW anyway. Why? Because your panels get dirty. There's always some power lost in the wiring. and your inverter isn't 100% efficient. Also, your panels degrade slowly over time. And panels are like people. They don't like working when it's too hot. — That's so hot. That was horrible. I'm going to die. I'm so tired. — Most systems only achieve about 80% of what they say on the box. So, if your system doesn't hit those perfect

### Segment 2 (05:00 - 08:00) [5:00]

numbers, don't stress. It's totally normal. Let me tell you how much energy you can expect from your solar panels, and I'll give you a dead simple way to work it out. First up, the quick answer. A typical 13 kW system in Australia pumps out around 52 kW hours per day on average. More in summer, less in winter. Now, here's a little trick I use. I call it the magic number. To estimate your daily solar energy, simply multiply your system size by four. So, you got a 5 kW system. 5 * 4, it's about 20 kwatt hours per day. Got a 10 kow system, 40 kwatt hours a day. But hang on a minute. This magic number does change slightly depending on where you live. Sunny Perf or Darwin are the best at 4. 6 while cold Hobart is the lowest at 3. 2. A couple of important things to remember. Firstly, these numbers are for north facing panels. You've got panels facing east or west, knock about 15% off. South facing, you'll lose about 30%. And these are yearly averages. In summer, you'll get much more. In winter, much less the difference between summer and winter generation gets bigger the further south you go. Compare Sydney's annual solar production to Hobarts. Now, let me clear up one of the biggest sources of confusion about solar savings, cuz this trips up almost everyone when they get their first bill after solar. — Why don't you explain this to me like I'm five? — Solar saves you money in two ways. First up, self- consumption. This is when you're using your own solar power instead of buying it from the grid. Secondly, you've got the feeding tariff. When your panels produce solar surplus to your home's requirements, that extra solar goes back into the grid. Your power company pays you for this. Not much these days, but hey, it's better than nothing. Now, here's the bit that drives people crazy. I get emails like this all the time. Mate, I just got my first bill with solar and it's only showing $100 in savings. I've been ripped off. Hold your horses. That $100 is just your feeding tariff. What you can't see on the bill is all the money you save by not buying power from the grid in the first place. Like I said, your power company can only see what goes in and out of your house. They can't see what's happening inside with your solar, so they can't print that on your bill. And that's exactly why I'm so insistent on getting this thing called a consumption monitor. It sits in your switchboard and it shows you how much money your solar is really saving you. And you see it through your inverters app. Don't buy solar without a consumption monitor. And don't let the installer leave until she's shown you that the app is working and exactly how you use it. So that's the absolute basics of how Solar works. Still got questions? Email my Adelaide based support team. Support at solarquotes. com. au. Looking to get quotes from installers I trust. Visit solarquot. com. au. Pop in your postcode, fill in the form, and we'll connect you with up to three great installers.