Automatic Energy Cost Savings: With Solar power and the SMA Sunny Home Manager

The best way of cutting your electricity costs as much as possible is simply to turn on your home appliances when your rooftop PV system is generating electricity. The problem with that is that we are often at work or otherwise not at home in the middle of the day when the PV system is generating the most electricity. This means that we can’t switch our appliances on ourselves. That’s why we manage our home appliances automatically with the SMA Sunny Home Manager 2.0. It switches our home appliances on when the PV system is generating sufficient electricity. Read on to find out how we can use this system to save hundreds of euros on electricity costs every year.

How to save money with solar energy

Modern PV systems generate electricity that is much cheaper than any you could purchase from the utility grid. You can achieve the best savings by switching on your energy-intensive home appliances, such as dishwashers, washing machines and dryers, only when the PV system is currently producing power. Directly using solar energy from your own PV system in your home is referred to as “self-consumption”.

Using the Sunny Portal monitoring system and the SMA Energy app, system operators can keep an eye on their PV systems at all times. At this time, the Partlin family is using 63% of the solar energy it is generating directly for home purposes (self-consumption) and supplying 77% itself (self-sufficiency), which means that the family needs to purchase only 23% of its electricity from the utility grid.

How do I switch things on when I’m not at home?

On the average day, we’re often not at home when the PV system is generating electricity. We might be at work, at school or university, doing our shopping or visiting friends and family. At first glance, it’s not quite so easy to make sure that our home appliances spring into action just in time for our PV system to be supplying energy.

So what is the solution? That’s easy: leave it to the Sunny Home Manager.

Automatically switching appliances on and off

As part of our family’s solar journey, we have integrated several compatible automatic load-break switches controlled by the smart Sunny Home Manager.

How does it work?

We have connected the Edimax load control sockets to our Wi-Fi network. The Sunny Home Manager communicates with them so it knows how much energy each appliance uses. It then does some pretty advanced calculations based on weather data (sourced from the internet), knowledge about how the PV system has performed and is expected to perform, plus historical information about how the appliance uses electricity. All of this is put together and the Sunny Home Manager can then decide when the appliances should be switched on so as to ensure that as much as possible of the energy consumed comes from the PV system. It passes this information on to the switches, which then switch the appliances on at the correct times.

Smart home energy management: The Sunny Home Manager 2.0 can be connected to all major home appliances via Wi-Fi and radio-controlled sockets and optimizes the Partlins’ energy consumption. It automatically switches on home appliances with flexible usage times when the PV system is supplying energy, which means that the family cuts down on electricity costs and receives recommendations for saving even more energy.

What appliances are best suited to being controlled?

The appliances that are best suited to automatic load control via sockets are those that do not have fixed switch-on times. We have fitted our dishwasher, washing machine, dryer and swimming pool pump (a very important appliance, at least here in Australia!) with load control sockets.

Tip: To check whether an appliance is suitable for automatic control, just switch it on and then use the socket to switch it off. Wait two minutes and then turn it back on. If the cycle starts operating again and does not require you to press any buttons on the appliance, then it can be controlled by a load socket.

How much did we save, and what did we learn?

From June to October (I live in Australia, so that means winter), the load control switches saved me around $150 (just under €100) simply by making sure my appliances consumed electricity primarily when my PV system was supplying energy. If that continues for the whole year, that’s an extra saving of around $400 (almost €250) annually.

Helpful conclusions about the energy consumption: With the SMA Monitoring the Partlin family can track exactly what percentage of their connected devices are supplied with solar or grid power.

We also learned that the load control sockets give the Sunny Portal a lot more information. That in turn makes it easier to make sensible decisions about our energy use. Also, thanks to the Sunny Home Manager and all the extra energy-saving tips that it gives us, we can use our PV system to save energy even with appliances that aren’t connected to a load control socket. All we have to do is use the delay timer function that many appliances have. This isn’t quite as accurate as automatic control through the Sunny Home Manager, but it’s sometimes quicker and easier when we’re running out of the door to go to school or work.

So if you want to save more money with your PV system, make sure you turn on your appliances while the sun is shining. And the easiest and most automated way to do this is to use automatic load sockets controlled by your SMA Sunny Home Manager.

Want to find out more about smart energy management?

To Sunny Home Manager 2.0

Do you have any questions about SMA Sunny Home Manager 2.0 or energy management in general? If so, please feel free to comment. I’ll get back to you as soon as I can in another blog post.