Another electricity tracking tool is available with more detail cost on display unit. Unlike the Spark Lamp, Wattson is not solar powered. But both of them has their own disadvantages and advantages.
I love Spark Lamp mainly because of the solar powered feature. But I’m also have a good interest on Wattson since it can display the cost in kWh or dollars.
Just plug it into your electricity counter of your pad and it shall do its job pretty well and real-time showing your energy usage through the LEDs display unit.
Wattson’s color goes from blue to red the more energy you use. The goal is to reduce the amount of electricity you use, and it’s been shown that Wattson helps to reduce the cost of your electricity bill by 5 to 20%.
— by Apartment Therapy
If you really want to reduce your energy usage, you have to check Wattson out at DIYKyoto for £99.95 a piece.