Fuel systems, energy comparison

H. Ide et al., "Natural Gas Reformed Fuel Cell Power Generation Systems - A Comparison of Three System Efficiencies," Proceedings of the 24th Intersociety Energy Conversion Engineering Conference, The Institute of Electrical and Electronics Engineers,... 

BASIS FOR ENERGY COMPARISON OF GASOLINE AND GASOHOL FUEL SYSTEMS... 

I. (2014) A comparison between renewable transport fuels that can supplement or replace biofuels in a 100% renewable energy system. Energy, 73, 110-125. 

If possible comparisons are focused on energy systems, nuclear power safety is also estimated to be superior to all electricity generation methods except for natural gas (30). Figure 3 is a plot of that comparison in terms of estimated total deaths to workers and the pubHc and includes deaths associated with secondary processes in the entire fuel cycle. The poorer safety record of the alternatives to nuclear power can be attributed to fataUties in transportation, where comparatively enormous amounts of fossil fuel transport are involved. Continuous or daily refueling of fossil fuel plants is required as compared to refueling a nuclear plant from a few tmckloads only once over a period of one to two years. This disadvantage appHes to solar and wind as well because of the necessary assumption that their backup power in periods of no or Httie wind or sun is from fossil-fuel generation. Now death or serious injury has resulted from radiation exposure from commercial nuclear power plants in the United States (31). 

Beckervordersandforth, Ch., An economic comparison of cogeneration systems, Proceedings, Fuel Cells in the Energy Market, Cologne, 12-14. March 1996. 

In Section 7.3, process-specific technical information on alternative fuels, which is needed for the WTW analysis is presented, and in Section 7.4 drive-system-specific data are provided, which are then merged in a WTW analysis of complete energy chains in comparison in Section 7.5. In reality, the potential number of realistic alternative fuel chains and drive system combinations is much larger. Owing to limited space, a set of most relevant processes is presented. A separate section (7.6) discusses the resource utilisation of the energy chains presented in Section 7.5. Section 7.7 finally combines specific GHG emissions for relevant alternative fuel supply chains with specific costs in a portfolio analysis. 

When one considers the early 2000 s, it can be expected that about one half of the thermal energy will be supplied by natural gas, and the rest by petroleum fuels (fuel oil and residual oil) and coal. Coal is assumed to be the main energy source for electricity generation, gasoline for surface transportation, and jet fuel for air transportation. This is of course a simplified version of the fossil fuel energy system, but it is close enough to the present patterns of energy consumption, and can be used as the basis for comparisons. 

The economical comparison between competing energy system should be based on the effective costs of the services these fuels provide. The effective costs include the utilization energy, the east of fuel, and the costs associated with fuel consumption but which are not included in its price (so-called external costs). External costs include the costs of the physical damage done to humans, fauna, flora, and the environment due to harmful emissions, oil spills and leaks, and coal strip mining, as well as governmental expenditures for pollution abatement and expenditures for military protection of oil supplies. 

For closed-cycle applications, such as for spacecraft, submarines, or transportation vehicles, the combinations of lightweight, reasonable power density, and compact size are favorable features in comparison with equivalent-capacity battery-based systems. In the International Space Station, for example, both electricity and water are provided by fuel cells. Fuel cells have not only been used in space exploration, but also in submarines (because they generate no noise or vibration). They have also been used to recover the energy from methane that is generated by wastewater, by garbage dumps, and more recently in automobiles as an alternative to the IC engine. 

Vicente, G., Martinez, M., Aracil, J., A comparative study for vegetable oils for biodiesel production in Spain, Energy Fuels, 20, 394-398, 2006 Vicente, G., Martinez, M., Aracil, J., Integrated biodiesel production a comparison of different homogeneous catalyst systems, Bioresource Technol., 92, 297-305, 2004... 

---