Example NZ map (javascript/d3/TOPOjson).
d3/svg regions loosely based on Grid Exit Points (GXPs) supplied area through NSP/ICP mapping.
Regional mappings supplied by Electricity Authority. Real Time Price data obtained from wits.
Currently svg mappings are based on GXP regions (out-dated) where a GXP is mapped to individual NSP/ICPs.
With updated wits data (every five minutes), can be used to plot real-time spot prices in the NZ Electricity market.
http://djhume.github.io/nzmap/
10/6/2013 DJHume & JMiller