Unless the source of separated carbon dioxide lies directly above or next to a site for injection, it is necessary to transport the carbon dioxide to the site, usually by pipeline, although ships could in some circumstances be used for large distances.
The carbon dioxide will normally be compressed to a supercritical state (a temperature and pressure at which it shows properties of both liquids and gases) before transport. Because of its potential corrosive effects, water (and possibly some contaminants) is removed before transport.
The issue of transport has implications to the future siting of power stations. It would be prudent for any future fossil-fuel-fired power station to be sited only after giving careful consideration to future storage options.