Generation, of the energy carrier HYDROGEN In context ... - needs

NyOrka Page 17 12/18/2008The emissions from the manufacturing phase is dominated by the amount of steel that isused in the storage module and the filling station itself, as well as the volume of concretethat is necessary for the foundation. The NOx and CO emissions are also a typicalemission related to the combustion of fossil fuels, e. g. in diesel engines related totransportation of the manufactured modules to assembly site. The NMVOC emissionsalso come from the nickel from the electrolysers electrodes.Using hydrogen to buffer renewable energy systems, such as a network of windfarms orsolar plants, the electricity to run the operation would come from renewable sources asthey actually do in the case plant (at Grjóthals, Reykjavik Iceland it is fed electricity fromgeothermal- and hydropower). The largest impacts may shift to the manufacturing phaseof the module where the electricity comes from renewable sources.To illustrate the importance of the source of the electricity used for hydrogen production,Figure 7compares the key emissions using the UCTE grid and the Icelandic electricity gridwhich is composed of 82% hydropower and 18% geothermal power).The absolute values are too different between categories to show in a single graph, so apercentage graph is used instead. Should the electricity be derived from wind turbines theenvironmental impact would be even become less than for the Icelandic grid mix.Grid mix comparisonUCTE MixIS Mix100%90%80%70%60%50%40%30%20%10%0%CarbondioxideCarbonmonoxideNitrogenoxidesSulphurdioxideGroupNMVOC toairMethaneFigure 7 Comparison of key emissions using UCTE electricity grid and the Icelandic electricity grid.3.2 Additional informationTemporal disaggregationThe temporal disaggregation means the duration of and time between the phases withreference to start of commercial operation. Table 7 shows the values for the referencehydrogen production facilities with year number 1 as start year of commercial operation