## 3 Results and Discussion
### Future Research Directions  
One feasible alternative to be analyzed consists of using the hot effluent from the reactor for the stream preheating in a first preheater and the utilization of the available energy in the exhaust gases coming from ICE and GT in a second preheater. In this plant scheme, an external fuel supply is required. In this configuration, there is a reduction in  
Figure 13: (**a**) Electricity generation of the GT and (**b**) electricity generation from hot effluent leaving the reactor versus the reactor inlet temperatures in the range from 450 to 520 \({}^{\circ}\)C. Both figures are parametrized as functions of the glycerol mass concentration in the feed stream. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Parameters Analyzed**} & \multicolumn{4}{c}{**Glycerol Mass Concentration in the Feed (wt.\%)**} \\ \cline{2-6}  & **10** & **15** & **20** & **25** & **30** \\ \hline Electricity from the GT (kW) & 593.1 & 575.8 & 558.6 & 541.3 & 524.8 \\ Electricity from the reactor hot & & & & & \\ effluent (kW) & 91.2 & 89.7 & 88.4 & 87.1 & 85.6 \\ Total Electrical Power (kW) & 684.3 & 665.5 & 647.0 & 628.4 & 610.4 \\ Fuel thermal power (kW) & 1976.9 & 1919.4 & 1861.9 & 1804.4 & 1749.6 \\ Glycerol thermal power (kW) & 444.4 & 666.7 & 888.9 & 1111.1 & 1333.3 \\ Syngas thermal power (kW) & 176.6 & 263.9 & 350.8 & 437.9 & 525.1 \\ Electrical efficiency 1 (\%) & 34.61 & 34.67 & 34.75 & 34.82 & 34.90 \\ Electrical efficiency 2 (\%) & 28.26 & 25.74 & 23.52 & 21.55 & 19.80 \\ Electrical efficiency 3 (\%) & 35.55 & 35.94 & 36.27 & 36.57 & 36.83 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Summary of the results of case study B when the reactor inlet temperature is 520 \({}^{\circ}\)C.  
the exhaust gas flowrate from ICE/GT when compared with cases A and B, which also decreases the size of the engines and, therefore, the capital cost of the plant. A rough estimate gives a power reduction of approximately 70%. Another option is hybridization with solar thermal energy, thus, considering energy storage, by heating a heat transfer fluid (HTF) by means of cylindrical-parabolic solar concentrators. This HTF (for example, Therminol) can be heated to 400 \({}^{\circ}\)C without degradation and would be suitable for the first preheating in the SCWG process. With this solution, there would be an important reduction in fuel consumption, thus, maximizing the overall efficiency of the entire plant. Additionally, the storage of thermal energy (STE) by molten salts would allow a continuous mode of operation in the plant 24 h per day. However, the maximum allowable temperature of Therminol can affect the conversion of organic waste and an additional heat source is necessary to achieve at least 500 \({}^{\circ}\)C at the reactor inlet, thus, increasing conversion. For this purpose, three different methods can be conceived using:  
- the energy available in the exhaust gases coming from ICE and GT in a second preheater;  
- thermal energy from the output of the reactor in a second preheater, or;  
- an autothermal reforming (ATR) process, involving a partial oxidation along with the gasification reactor inlet (SCWG). In this way, enough oxygen/air should be entered the preheater outlet to achieve the set point temperature (\(\sim\)500 \({}^{\circ}\)C). This solution would reduce the produced syngas as a fraction of the organic waste that is oxidized. One more feasible alternative is the hybridization with an SOFC-type fuel cell, in which electric power is generated by feeding with two streams, one is air and the other is H\({}_{2}\) (or light hydrocarbons), which could come from the SCWG process itself. H\({}_{2}\) is recirculated and the exhaust is a stream of steam and air (or gas, if hydrocarbons are used) between 900 and 1000 \({}^{\circ}\)C, allowing the SOFC fuel cell to hybridize with the SCWG process.