Other Energy Monitoring projects
The EnerJar Project, the do-it-yourself power meter that won the 2008 greener gadgets design competition. The guys behind EnerJar - Matt Meshulam and Zach Dwiel built a very informative site detailing their design. Unfortunately they decided to stop development due to safety problems with the design and so the project has been inactive for some time.
Cliff Jao and Xi Guo's PowerBox. An energy monitor designed and built for their final year project at Cornell, these guys came up with a much safer design using two HCPL-7520 opto-isolator chips. Be sure to check out their page there's a lot of useful info there.
Limor's tweet-a-watt takes a Kill-a-watt power monitor, modifies it with an xbee, wirelessly sends power usage to a computer which then tweets the power usage values to twitter, plenty of great information about how to build it, a great example of energy monitoring and the potential of linking it up with social networking. Limor's site ladyada and adafruit industries are also full of great open hardware projects.
Home power Monitoring
John from jarv.org has developed a whole house energy monitor, using CT sensors and posting the data to a web-server using an ethernet shield. The ethernet arduino and web-server script used in this project is based on his work.
Ronic Concepcion and Ymreb Momville from the University Southeastern Philippines are undertaking a technical research project calledOpenCO2Monitor as a part of their BS Information Technology degrees. Their project is a collaboration with this project using the Mains AC:Non-invasive method of energy monitoring to supply energy consumption information to their software.
Wind speed Monitoring and turbine output prediction
I meet Richard who has the website above in the Small is.. festival during the summer of 2009. He has been monitoring wind speeds using an anemometer mounted to a sailing mast and then a wireless link to the local broadband network that he runs. He then uses the anemometer wind speed reading and the wind turbine manufacturers power curve to estimate how much energy a wind turbine would produce at the location.
Re-innovation is Matt Little's website which has information on PV installations, wind turbines and bike generator building instructions. Matt Little is also building energy monitors, specifically to measure the state of charge of 12V lead acid batteries.
GPL'd, Linux-based, power management system for off grid houses. Looks really interesting!
Open Source Energy Management Software uses Cacti and RRDTool, a great project started by Alexander Bischoff.
Real time web based power charting
A good example by Jason Winters of using a current clamp for measuring current and internet connectivity using an ioBridge.
Simple power monitor
A project by Wichit Sirichote, current measurment with a CT sensor and an LM324 to provide short circuit input.
A great project by Adrian McEwen. It uses similar electronics to the mains invasive method part of this project. The designs are not available online yet (as far as I know), but there are kits available.
A project by James Devine, he has been developing an open source arduino energy monitor based on an Analogue Devices ADE 7753 IC which is a custom energy meter IC for use with CT sensors. The ADE7753 looks like a really good way of doing the measurement, it communicates with the arduino via SPI and does all the energy metering calculations itself, therefore freeing up the arduino for other tasks.
Application notes. Guides from the manufacturers, full of useful info.