“A negawatt is electricity that’s saved by using it more efficiently or at a smarter time. So, you don’t need to produce it to get the same hot showers, cold beer, or other effect that you want.” — Amory Lovins
OK, so that’s what these devices are for… helping you to identify ways to save on your electricity bill. Usually by identifying phantom loads (computers, TVs, etc. which pull lots of watts even when “off”.) Or inefficient or broken appliances.
In the order of least to most expensive choices: there are ones that you plug in to a single outlet (Kill-A-Watt), and others that monitor your whole house (Powermeter and TED 5000), and now there is one that will monitor every circuit (usually a room or 2) in your house (Powerhouse eMonitor).
Even if you spent the almost $1000 on the eMonitor, I bet most people would break-even on the cost in less than $5, according to MA electricity rates circa 2010 of $.20/KWh. I can easily see people finding easy ways to cut their bill by $15 month, so that’s almost $200/year. So $1000 / $200 = 5 years. And after that… free money thanks to negawatts.
Erik's Blog 