Hello,
this is my first mail to this list. I am active in the openstreetmap project since two and a half year, but i got a toolserver account and started to learn mapnik only one month ago. My first project is an overlay map of power lines, cables, generators and (sub-)stations. The maps displays power lines depending on "voltage" and generators depending on "power_source"/ "generator:source" and "generator:output:electricity". You can find the style file (power.xml) and a few examples on http://toolserver.org/~seawolff/ . All examples are from northern Germany. I am interested in feedback and suggestions. A power map with a bw_mapnik map as background may be useful. The map on http://energy.freelayer.net/ has not been updated for many month and has some technical defects. I didn´t find detailed power maps from other sources on the web.
Regards, Stephan Wolff