16 December

A less well known way to heat your hot water (up to 30% or more of a household's energy costs) with solar is a hot water PV diverter. These clever devices take any excess solar you may be producing, and feed it to your electric hot water heater in chunks that make it work. For example, if your electric hot water has a 4.5 kW element, but you're only producing 2kw of surplus solar at that time, the diverter will drip-feed your 2kw surplus to the hot water heater in a way that still makes the 4.5 kW element work. Not as useful if you live somewhere cold, like I do, where in winter you may not have much if any excess solar. But if you live on the coast for example, these are a great idea, because you can use the old-style electric hot water storage heaters, which are pretty cheap and were being phased out until diverters came along.