Typically, a system will consume a small amount of electricity to run the pump and controller – less than £10 per year. When running, it will be virtually silent. It will provide between 40-60% of your hot water needs. The vast majority of that will be from April to September; don’t expect great things in the winter – probably around 15%. In the summer, a typical system could deliver a full tank of hot water at 60°C – too hot to shower in.
Modern systems are automated. You don’t have to decide when to switch it on and off – it does it for you. You don’t have to re-set any clocks after power cuts; and you don’t have to change how and when you use hot water (although if you do, you may get more benefits from your system – for example, if you change from having a shower in the morning to the evening).
If you want to engage with your system, depending on the components you have, it can give you some interesting figures, such as the temperature in the panels, or at the top or bottom of the cylinder. This is useful because these figures will often be more accurate than those you can get from the boiler controls, and so you can use them to fine tune the boiler controls, and save a bit more money.
If you want to get a bit geekier, some systems can give you more information – such as the cumulative solar gain, or the solar contribution over a day, a week or a month, and some have graphic displays so that you can see trends.
You’ll get a surprisingly warm glow when you’ve had a solar shower – just knowing that the sun has heated your water and reduced your energy bills and carbon footprint.