Pneumatic hybridization of a diesel engine using compressed air storage for wind-diesel energy generation

In this paper, we are studying an innovative solution to reduce fuel consumption and production cost for electricity production by Diesel generators. The solution is particularly suitable for remote areas where the cost of energy is very high not only because of inherent cost of technology but also due to transportation costs. It has significant environmental benefits as the use of fossil fuels for electricity generation is a significant source of GHG (Greenhouse Gas) emissions. The use of hybrid systems that combine renewable sources, especially wind, and Diesel generators, reduces fuel consumption and operation cost and has environmental benefits. Adding a storage element to the hybrid system increases the penetration level of the renewable sources, that is the percentage of renewable energy in the overall production, and further improves fuel savings. In a previous work, we demonstrated that CAES (Compressed Air Energy Storage) has numerous advantages for hybrid wind-diesel systems due to its low cost, high power density and reliability. The pneumatic hybridization of the Diesel engine consists to introduce the CAES through the admission valve. We have proven that we can improve the combustion efficiency and therefore the fuel consumption by optimizing Air/Fuel ratio thanks to the CAES assistance. As a continuation of these previous analyses, we studied the effect of the intake pressure and temperature and the exhaust pressure on the thermodynamic cycle of the diesel engine and determined the values of these parameters that will optimize fuel consumption.

► Fuel economy analysis of a simple pneumatic hybridization of the Diesel engine using stored compressed air.
► Thermodynamic analysis of the pneumatic hybridization of diesel engines for hybrid wind-diesel energy systems.
► Analysis of intake pressure and temperature of compressed air and exhaust pressure on pressure/temperature during Diesel thermodynamic cycle.
► Direct admission of compressed air reduces fuel consumption through positive work of low-pressure Diesel cycle and reduction of thermal losses.
► Optimization of air intake temperature/pressure and crankshaft angle to improve the ratio fuel consumption/mass of air.