Q: What is the EnerJar?
A: The EnerJar is an open source watt-meter. It measures the amount of energy an appliance is using. You can use it to find out just how much energy it takes to run a microwave, TV or Laptop. Figure out what requires the most energy and give it a break. Or see if you can figure out how to use it in a way that requires a little less energy. Try measuring how much energy your TV uses while it is off. You might be surprised!
Q: When will these be available?
A: Kits to build these yourself will be available in the near future. The design is posted here for those of you who can find all of the parts yourself and have a PIC Programmer and some basic soldering skills. There are currently no plans for commercial mass production, but we are still investigating how we might distribute these and are open to suggestions. We would like to make them available to as many people as possible.
Q: How hard will this be to build?
A: The only tool required will be a soldering iron, required for nearly all DIY projects of this sort. A drill, voltmeter and a little knowledge or willingness to learn basic electronics are a plus, but we hope, not required. Our primary goal is to make these as accessible as possible so we will work on making it simple. However, remember that the EnerJar's circuitry involves 120-volt AC power, which can hurt or even kill you if you don't take the proper precautions. Never touch any of the wiring or circuitry when the EnerJar is plugged in.
Q: How much will they cost?
A: We are still working out the details. The current goal is to give away as many of these as we can afford. Yes, thats right, free hardware. There will be a cost to send out the parts and then a partial or full refund when you send a picture of your working EnerJar. We encourage those of you who can pull parts from old electronics to do so. If you only need some of the parts, we plan on custom shipping only what you need to reduce waste.
Q: How can hardware be free?
A: Partly because we got money from the Greener Gadgets design competition. Partly because, we'll ... we're working on it. Donations to subsidize the cost for people who can't afford this wouldn't hurt!
Q: Does the EnerJar work with 240-volt AC?
A: It sure does! The only change required to make the EnerJar 240-volt compliant is that the R6 resistor should be changed to about 1.5M. The exact value is not critical because of the calibration process.
Got a question? Ask in the comments below!