Maximise your in-home use of solar 

It is best to use solar when the sun is shining. However, with solarZero® your savings are not based solely on the solar portion of your bill. As we know that the majority of Kiwis are not at home during the day, our solarZero® service doesn't rely on you being at home to get the benefits. Plus, we offer a buyback price guarantee for any surplus solar power that you don't use.

Here are some things you can do to become an energy-conscious consumer. 

Solar basics

Typically, solar produces the most energy between 9am to 3pm, with more power being generated during the long days of summer compared to the much shorter days of winter. With solar panels, the yearly electricity production graph usually resembles a bell curve. The low end of the curve represents the winter months and the peak is reached during summer. With our solarZero® energy service your home is powered by the grid when the sun's not shining. We've negotiated a special rate for our solarZero® customers so you get grid power cheaper than you can buy it from any of the traditional power companies. This means you'll be saving money day and night. 


By aligning your electricity consumption to your solar generation you will maximise the savings potential of solar. That does not mean you should turn on all your appliances from dawn to dusk. Here are some tips and tricks.

Making the link between solar power and appliance power ratings

The first step is to understand how much power the solar system is generating and how much power your electrical appliances are using. Your solar specialist/energy advisor, or installer, can also help you build an energy profile for your home.

Here are some general numbers to give you a guide.

Homeowner Power bill/month Solar system size (kW)
Low user $100-$200 1.7
Medium user $150-$300 2.6
High user $250+ 3.5

The per kW figure is important as it is the maximum amount of power your system can produce when the sun is shining, Now, compare this with the power rating of standard appliances in New Zealand.


Appliance kW 
Fan or two bar heater  2.4
Heat pump 0.7 - 2.0


Appliance kW 
Iron  1.4
Dryer  1.4
Washing Machine 2.0


Appliance kW 
Fridge 0.5
Freezer 0.3
Jug  2.4
Dishwasher 2.0
Toaster 1.4
Oven  1.9
Microwave 0.7


Appliance  kW
Spa pool 6.0
Hair dryer 1.6
Vacuum cleaner 1.1

Wattage varies from model to model. Figures are examples only.

To calculate how much the solar system can power in your home at any one time, start by listing the appliances that run continuously such as your fridge and the freezer. This is called the base load. You can then add other appliances that are used intermittently. This is the variable load which, ideally, is used during the daytime.

It is wise to stagger the use of high wattage appliances, like the dishwasher and washing machine, otherwise you may exceed the system's capacity and start using grid power as well. In other words, if you are using a 3kW rimu solar system and run a 2kW dishwasher and a 2kW washing machine at the same time, you will need more power than the system can supply (even in perfect, sunny conditions). This means the 1kW shortfall (or more, depending on what other appliances are being used) will automatically come from the grid.

Monitor your consumption

Making the most of solar power means adapting the way you use electricity. Stagger the use of major appliances so they are not all drawing power at the same time. Our solarZero® app lets you track how much electricity the panels are generating and how much energy your home is using. As part of our solar installation we wire your hot water cylinder so you can switch it on and off with a simple swipe of the solarZero® app. You have the same remote control of appliances connected to smart plugs.

Use energy intensive appliances during the day

Even top energy rated washing machines, tumble dryers and dishwashers can easily consume 1 kWh per cycle, so it makes sense to run them when the sun is producing the maximum amount of energy - typically between 9am and 3pm. If you are going to be out, set your appliances to run while you are away by using the in-built timer, or by adding a plug-in timer for each device. Set them to run in a staggered fashion as you may exceed your solar capacity if they are all using power at the same time.

Cut your water heating bills

A good way to ensure excess solar energy is not exported to the grid is to use it to heat up your hot water cylinder. Our solarZero® app gives you remove control of your hot water cylinder so you can turn it on during the middle of the day when there's plenty of solar power. 

Use a slow cooker

The slow cooker is perfect for making excellent use of your daytime solar power. With power consumption as little as 200 watts, it will save you money on cloudy days as well as sunny ones. 

Make more of your microwave

If you have a gas hob, and you lunch at home, consider heating your meal using your microwave while the sun is shining to help cut your gas bills. In fact, if you have a decent microwave, switch to cooking what you can in that instead of your main oven. Your microwave uses less kW and will cook the meal much faster, saving more energy in the process.

Replace old appliances

Armed with our previous tips, even less efficient appliances may well cost you nothing to use during daylight hours when the sun is shining, but it is still worth looking for the most energy efficient appliances when it's time to upgrade. This is particularly important for washing machines, dishwashers and tumble dryers. If you choose the most energy efficient appliances, you can use them earlier or later in the day, or when the conditions are not perfect, all without drawing power from the grid.  

Upgrade your kettle

Kettles are power-hungry appliances. A typical kettle is rated at 2.4kW which takes a huge draw on a average sized solar system, even though it is only on for a short time. A vacuum kettle has the ability to store the heat better, meaning it will take less time to heat if it has been used recently.