Tue, 06 May 2008
An interesting discussion appeared over on the NANOG mailing list, based on the article, Up to 300 Megawatt Worth of Keepalive Messages to be Saved by IPv6?
This points to an original study by Haverinin, Siren and Eronen at Nokia that shows how much energy is used via "keepalive" messages sent in VoIP, Instant Messaging and other systems, in order to satisfy NAT. In order to maintain connectivity through a NAT router these systems need to keep sending messages to stop the NAT router closing the connections. With IPv6 this would no longer be necessary. It turns out the power requirements are quite significant.
There is good work happening elsewhere in Linux and elsewhere in IT, to minimise the amount of energy wasted, such as the Less Watts project. But perhaps its worth doing an audit of the protocols we use, to see what energy savings we can use?
Wed, 30 Apr 2008
So, the solar panels are now installed, and heating. We're getting the water in the tank heated to around 50 C on these grey days; (there is also an electric immersion coil to heat to 60 degC as necessary, at night-rate electricity). They heat a 300L tank in the utility.
The panels are grant-aided by Sustainable Energy Ireland, and we reckon they'll pay for themselves in 5-8 years, depending on water usage with three kids. Time now to see what the actual savings are.