It might seem that solar power, since it comes from the sun, is only available when the sun is shining bright.
But no! Solar energy, once captured, is available 24 hours a day, 7 days a week to power our lives wherever solar panels are installed. If you outfit your property with a solar system, you can rest assured that you’ll have enough energy to use whenever you need it, even at night or on a cloudy day.
So, why does solar never take a break? Let’s explore a bit more about how it all works.
During the day: Your solar system at work
In the daytime, when the sun is shining, your panels are constantly receiving energy from sunlight. This energy is in a form known as photovoltaic (PV) energy.
Behind the scenes, your solar energy system is converting the energy into direct current (DC), which in turn is converted to alternating current (AC). The AC power is what you use at home.
This process is still occurring any time the sun is out, even on days that aren’t bright and sunny. During daylight hours on rainy or cloudy days, your solar panels still absorb sunlight, just not as efficiently as on cloudless, clear days. That means your solar panels are taking in less energy, but they’re still at work.
At night time, your solar panels are not receiving any power. That’s when you begin to draw on energy from the grid
At night: Using stored solar power
While at night when your solar panels are not actively generating power, you’re drawing on energy off the grid.
The process by which your utility company monitors the energy converted by your solar system is called net metering. As a part of your system’s installation and connection to the grid, a meter tracks the amount of excess power, as well as how much you’re using at home.
The excess energy is where your solar power savings come in. Assuming that you don’t use all of the stored energy during off-peak (night-time, or low sunlight) hours, you can ‘sell’ it or receive a credit for it from your utility company. This can result in large savings on your monthly bills.
Most New Zealand energy companies offer a buy back rate for households which generate excess energy with solar panels. Here’s what the following energy retailers offer (as of January 2018):
- Contact: 8 cents per unit
- Mercury: 8 cents per unit, or 12 cents for newly supplied solar customers that enter into a 3 year contract
- Trustpower: 7 cents per unit
- Meridian: 8 cents per unit
- Genesis: 8 cents per unit
- Ecotricity: 7-8 cents per unit
- PS Power: 16 cents per unit for the first 50kWh exported each fortnight, 8 cents thereafter
Your solar energy never runs out
Think of your solar system as a resource that’s working for you at all times. The panels constantly take in sunlight when it’s available, and the system converts it to a usable form for your home, and allowing you to draw off the grid when you need it
In the event that you use more power than you’ve stored, you’ll simply begin to draw on regular electricity from the grid. But to maximise your savings from solar — and possibly break-even — there are a few lifestyle adjustments you can make at home, such as running your biggest appliances during the day, switching to energy-efficient versions of them, and limiting your power usage at night.
When all is said and done...you can rely on your solar power system every day and night, every season of the year. Whether it’s raining, cloudy, or sunny, your system generates and feeds your home enough power to keep you comfortable, while helping you save on your power bills.