The need to reduce emissions of greenhouse gases could have major effects on energy transmission. CO2 from fossil fuels may need to be captured and transported to long term stores, for example deep saline aquifers or depleted oil and gas fields. This may affect the optimum location of energy conversion plants such as power stations. Also, novel energy carriers such as hydrogen may become more attractive. On behalf of the IEA Greenhouse Gas R&D Programme, Woodhill Engineering Consultants, in collaboration with Mott MacDonald, have developed a model for initial assessment of the costs and performance of energy transmission and CO2 capture. The model covers the distribution of energy in various forms such as natural gas, hydrogen, methanol, distillate oil, and electricity, and the capture and gathering Of CO2 using onshore and offshore pipeline transmission. Sensitivities can be assessed for a wide range of factors, such as the output of power stations, fuel supply flowrate, pipeline diameter, operating pressure, terrain and country. Cost estimation is based on industry standard techniques. The model also includes simple algorithms for the costs and performances of energy conversion plants, such as power stations and hydrogen plants, and for underground injection Of CO2. This paper contains a description of the model and includes several examples of predicted costs and performance of energy distribution and CO2 capture and transmission.