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Show 2 of 8 Figure 1 a): self regenerative FLOX® burner: Regemat® M250 Figure 1 b): self recuperative FLOX® burner: Rekumat® S150 Figure 1: High efficiency gas burners for industrial furnaces 3 of 8 Figure 2 - Effect of heat exchanger design on air preheating and exhaust gas losses More in general a comparison on the energy savings potential can be drawn for the different available solutions in the high temperature heat treatment industry as shown in Table 1. All figures refer to a quite representative application with 1000°C process temperature while the values of primary energy consumption as well as the related CO2 emissions are normalized with respect to the energy output to the heat treatment process. The assumptions on the characteristics of the electric power generation system refer to the German energy mix. The first case taken into account is the less efficient solution using natural gas heating systems with no heat recovery through air preheat. The efficiency will be approximately 50% and therefore the normalized primary energy consumption equals 2. The same consideration applies to the normalized amount of CO2 emissions. 4 of 8 The second case represents what can be considered the current standard in the high temperature thermal treatment industry: burners with integrated recuperative heat exchanges for air preheat with an exhaust outlet temperature of about 600 °C corresponding to a waste gas loss of 30%. Using natural gas burners with innovative design and optimized air preheating, such as with the WS self-regenerative and gap-flow self-recuperative FLOX® burners (Figures 1 and 2), reduces the waste gas losses by a factor of 2 with respect to the standard heating solution, that is 15% instead of 30 % energy loss. This is reflected in the lower energy consumption and CO2 emissions. Therefore, switching from the current operating heating systems (which is basically a mix of state of the art, electric and no preheat heating technologies) to innovative natural gas burners designs would importantly help to accomplish the goals set for 2020 by the European energy strategy. The comparison with oxy-combustion of natural gas shows that this solution does not represent a real step ahead with respect to the current state of the art since the primary energy consumption is significantly affected by the power consumption of the air separation units. Finally, the use of an electric heating system in the heat treatment industry is by far the least efficient solution originating the largest impact in terms of primary energy consumption and CO2 emissions. The previous "compact" analysis for high temperature industrial heating shows that the utilization of high efficiency FLOX® burners represents an important and profitable choice both in terms the reduction of primary energy consumption and care for the environment. At the same time this can be achieved in a convenient manner. 2.2 Middle and long term In fact, as far as these innovative gas burner designs are taken into account each saved kW on the gross capacity compared to the state of the art solutions implies additional costs in the range of 50 to a few hundreds $/kWth. In contrast, the cost for CO2 free power generating utilities, whether CCS coal, nuclear, solar or wind, would be typically in a range of few to several thousands $/kWel. Energy conservation is by far the most economical solution to reduce primary energy consumption and CO2 emissions. However, looking further to long term objectives set for 2050 it becomes clear that the huge step represented by the 80-95% reduction in CO2 emissions will require much bigger efforts 5 of 8 6 of 8 Table 2 shows a comparison in terms of fuel costs and CO2 emissions with 3 different types of vehicles already available on the market: a compact car with internal combustion engine, an electric car of the same size and a light-weight electric car. The figures show that combining decentralized CHP with light-weight electric mobility can represent a reduction in the CO2 emissions (from 130 to 16 g/km) that would fulfill the european energy and environmental requirements for 2050 (i.e. cutting down the CO2 emissions to 15-20% of the values in 1990) on a fossil fuel based system. Another highly beneficial effect is the reduction of fuel costs for the user. Prototype fuel cells CHP units with FLOX®-Steam-Reforming were installed in 2012 and at the beginning of 2013 in Germany demonstrating the profitability of this technology for private housing combined with satisfactory reliability. These installations are being permanently monitored in order to collect data for the evaluation of the actual performances of the system. In the winter season about 80% of the electrical energy demand of the building was covered by the CHP unit while the thermal power was used for hot sanitary water and partly for the heating (this unit has been integrated into an existing installation and has priority on the conventional heating system). In the summer time, since the energy demand for hot water is lower and usually no heating is required, it would be ideal to combine such a system with the right amount of photovoltaic panels. 7 of 8 8 of 8 |