Home Power Management using an Energy Monitor

Good monitoring is valuable knowledge to enable you to effectively manage your Renewable Energy power system.

Health practitioners often tell us we need to get in tune with our body. Similarly, you need to tune into your Renewable Energy system to get the most out of your system and to maximise the life span of your batteries. The lifespan of batteries is proportional to the number of discharges, the depth of these discharges, and how long the battery remains discharged.

Shunt and Shunt Adaptor

Since we have been selling the Plasmatronics PL regulators, I have noticed a big improvement in how people understand and manage their systems. As a company, we strongly encourage our customers to spend the extra $200 for the shunt adapter and shunt. This allows you to monitor the instantaneous current (amps) as well as amp-hours used per day. When the Plasmatronics regulator is configured with this option, it will then give you an exact battery State of Charge expressed as a percentage – eg 88% charged. No more looking at battery voltage or specific gravity to guesstimate this figure. If you turn one appliance on at a time, you can then learn what each one uses.

The power consumption of an appliance is often not easily determined by looking at the compliance label on the appliance, which tends to give a maximum but continuous rating. So your washing machine might say 1500W but it will only use a couple of hundred watts if the water-heating element is not used. Appliances, like washing machines and bread ovens, perform several functions all using differing wattages. A lot of computers and home entertainment appliances use less than that stated on the label. On the other hand, a microwave oven often uses 50% more power than the glossy label on the front would have you believe.

Energy Monitor

For those of you who do not yet have such a useful regulator, we can now offer you a pocket size Energy Monitor. These meters measure several functions including watts and watt hours. So now you can know exactly how much power that load of washing or that loaf of bread uses. A power monitor is also very handy for installers and designers of systems to work out exactly what one’s electrical loads are on a case-by-case basis.

The end purpose of such system monitoring is to be in tune with your system with a view to getting a long life out of your batteries. It also allows you to get the best value from your system.

With this knowledge together with the weather forecast you might conclude that you will have surplus power today. So this would be a good day to:

  • stock up your fridge
  • pump some water
  • defrag your computer and burn some DVDs
  • play with your Game Boy
  • use your bread oven (why use gas if you have surplus solar power?)
  • do the washing.

On the other hand if your batteries are low, you might want to try and reduce some of your power needs that are not particularly necessary.

We also found that a lack of knowledge can lead to inappropriate decisions, for example, turning off the small radio to save power while leaving the desk top computer on all day, for no good reason, in the mistaken belief that computers don’t use much power.