Our house is a detached single-family dwelling, built in 1998, with one finished floor of 2000 square feet (186 square metres) with a full partially finished basement of 2000 square feet. Since our only energy source is electricity, the main challenge is to reduce energy wasted for space heating (using conventional electric baseboard heaters throughout) and hot water (using a conventional storage type electric water heater).
The graph at the right shows our average daily consumption per two month billing cycle for the past 2.5 years or so. We've managed to cut our electricity use by just under 20% over the first year's baseline, saving a total of approximately $620 (at an average price of 7 cents per kWh).
Part of this savings in the past year is due to a relatively mild winter on the South Coast of British Columbia in 2009/2010. On the other hand, we had an extended cold snap last winter (2008/2009).
The rest of the savings I attribute to
After the usual amount of sys admin fiddling, I've moved most of my Drupal sites onto a new server: an Apple 1.66 GHz Core Duo Mac Mini. Over the coming weeks I'll be doing some performance tuning and testing to see how it stacks up against the old server, a Dell SC 1425 dual Xeon box.
I wiped the Mac Mini's drive and installed Ubuntu 9.04 server, which took a bit of fussing, but turned out to be pretty easy once I figured it out (more details on that later; basically I had to install 8.04 and do an online upgrade to the newest version)
The box is sitting beside me - tiny, silent, consuming only 23W or so at idle, 110 at full CPU, compared to almost four hundred watts for the old server. Actually, I suspect that these figures are a bit on the high side. I'm planning to actually measure the power consumption, but that's a project for another day. I suspect that the humble Mac Mini has one of the best performance ratings per Watt consumed of any server anywhere. The new (2009) ones are even leaner. I have to say that I'm in awe of this little box.
It's running 'headless' (needs no monitor or keyboard to boot up) thanks to a bit of hardware hackery that I found here. I took photos and documented the (pretty quick and easy to do) assembly of the dongle in this flickr photoset.
Next steps: install a faster, more robust drive (perhaps an SSD?) and get SELinux working. Also web performance benchmarking.
Just reblogging from teaching.puregin.org: I posted my slides and some other material from my OpenWeb Vancouver 2009 talk on “Open Books, Open Minds, Open Source”. This talk explored how the conception of “openness” in information and knowledge, in the context of teaching and learning mathematics, has changed over the past 2400 years of mathematics education.
In particular the timeline of Education and Technology technology which I made can be found here: http://www.puregin.org/exhibits/edtech/edtech.html
Using current 'baseline' solar photo voltaic (PV) electric technology, solar farms covering approximately 2.85 percent of the area of the Sahara desert could generate enough electricity to equal the energy generated worldwide in 2005 from fossil fuels.
Such a solar array would cover approximately 256,500 square kilometers (somewhat larger than Honshū, the largest island of Japan) and cost in the neighbourhood of 150 trillion US dollars to construct, assuming costs of about $500 per square metre of PV cells.
Today, the first day of Spring, marks my second commute of the week on my relatively new bike, an Ezee Forte electric model. If you've been following along you'll know that the first few rides left me less-than-impressed with the electrical system.
If you've been paying attention, you'll know that we've been down to a single car for the last month or so. Last weekend, after a good deal of discussion, we bought a new vehicle: an electric bike. The goal is for this to replace one car for my 4 times per week 20km each-way commute, thus saving 80-120Kg CO2e per month over taking my 2004 Golf TDI (the numbers are from this article). So, we made the trip to Victoria to Scooter Underground.
I started thinking about the whole concept of 'print on demand' a.k.a. 'just-in-time printing' yesterday after I printed off 304 pages of Squeak By Example, an introduction to the Squeak implementation of the Smalltalk programming language. The book is available under a Creative Commons BY-SA license, and is freely available for download, though I elected to support the authors by purchasing the PDF from Lulu.com for $8.95 USD.
I greatly enjoyed Zak Greant's keynote talk at OpenWeb 2008 on The Age of Literate Machines in which he reminded us of the many attempts by rulers and government over the ages to curtail freedoms such as the ones defining "Free" software.