Seite - 68 - in Our Car as Power Plant

68 We now compare the system effi ciency for the coal and gas power system with the car-park power plant system with gas as fuel. Based on the same system boundaries we see for the fossil-fuel power plant system an effi ciency of 38% and for the car-park power plant system an effi ciency of 45%. This means an overall energy-effi ciency improve- ment of almost 20% in our electricity system. This would imply also that the carbon dioxide emissions will be some 20% lower. On top of that, a fuel cell car-park power plant has no other local emissions to the air and is very quiet. OUR CAR AS POWER PLANTENERGY EFFICIENCY ELECTRICITY PRODUCTION BY POWER PLANTS COMPARED TO CAR PARKS FOSSIL-FUEL POWER PLANT SYSTEM CAR-PARK POWER PLANT SYSTEM Extraction coal/gas + transport 95% Extraction gas + transport 95% Gas to hydrogen (H2) 80% Power plant system 40% Fuel cell car park system 60% Other system component effi ciencies the same Overall Effi ciency 38% Overall Effi ciency 45%