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The processing of ambient air by vapor compression and exhaust heat conversion refrigeration machines with heat removal from them to atmosphere by the circulating cooling systems are studied. Ambient air cooling is conducted by using different types of refrigeration machines: absorption lithium-bromide refrigeration machine (ARM), utilizing the exhaust gas heat of gas engine, combined absorption-ejector refrigeration machine (AERM) and electrically driven vapor compression refrigeration machine (VCRM). The data on current thermal loads on refrigeration machines of different types and their circulating cooling systems with dry cooling towers (air condensers in the case of VCRM) for different their project thermal loads were obtained through modelling their current loading in accordance with actual climatic conditions. The efficiency of performance of refrigeration machines of different types (ARM, combined AERM and VCRM) to provide the target temperatures of cooled air is estimated by annual production of refrigeration according to ambient air conditioning duties. It was shown, that the most energy-efficient refrigeration machine is the ARM, while the most energy-consuming was VCRM.

Natural hollow spaces in the rock mass (caverns) or underground mining excavations can be used as compressed air storages with which electricity can be stored (a significant problem may be the leakage of these spaces; another well established way of storing electricity is to store it with the energy of potential water in the upper reservoirs of pumped hydroelectric power plants).

The chapter includes an economic analysis of unit hydrogen production costs in the water electrolysis process in the system with the gas–gas engine—Fig. 5.1. But not only. For comparative purposes, we present also the values of the cost for all remaining power generation technologies.

Reciprocating gas engines are widely used in integrated energy systems (IES) for combined cooling, heat and electricity supply. The fuel efficiency of gas engine considerably depends on the air temperature at the inlet of turbocharger. To estimate the influence of inlet air on gas engine fuel efficiency the data on dependence of fuel consumption and power output of gas engine on its inlet air temperature were received for Jenbacher gas engine JMS 420 GS-N.LC of cogenerative type with using the heat of exhaust gas, scavenge air, engine jacket cooling water and lubricating oil for heating water to the temperature of about 90 ℃. The hot water is used in absorption lithium-bromide chiller to produce a chilled water, which is spent for technological needs and feeding to the central air conditioner, that provides cooling ambient air incoming the engine room, from where it is sucked by the engine turbocharger. The data on dependence of fuel consumption and power output of gas engine on its inlet air temperature received by processing the monitoring data are very usefull for improving the efficiency of conventional cooling system with chilling the engine room incoming air followed by heat influx from surroundings, that leades to increased air temperature at the suction of turbocharger and enlarged cooling capacity spent for cooling.

The efficiency of cooling air at the inlet of gas engine was investigated for combined electricity, heat and cooling generation in integrated energy system (IES) at the factory “Sandora”–“PepsiCo Ukraine” (Ukraine). The IES is equipped with two cogenerative Jenbacher gas engines JMS 420 GS-N.LC, in which the heat of the exhaust gases, scavenge air-gas mixture, engine jacket cooling water and lubricating oil is used for heating water to the temperature of about 90 °C. The hot water is used in absorption lithium-bromide chiller to produce a chilled water with temperature of 7 °C, which is spent for technological needs and feeding to the central air conditioner that provides cooling ambient air incoming the engine room, from where it is sucked into the engine turbocharger. A treatment of monitoring data on fuel efficiency of gas engine has proved inefficient operation of conventional cooling all the engine room incoming air followed by heat influx from surroundings, that leads to increased air temperature at the suction of turbocharger and enlarged cooling capacity spent for cooling. An advanced system of gas engine inlet air deep cooling by chilled water from absorption lithium-bromide chiller, subsequently subcooled by boiling refrigerant of ejector chiller, recovering waste heat of engine, has been developed. The proposed new system provides decreasing current specific fuel consumption by 2.5–3.0 g/kWh due to stabilized low temperature of air at the suction of engine turbocharger at increased ambient air temperatures.

Natural gas today is of increasing interest, as it allows to reduce harmful emissions into the atmosphere. The environmental impact of large parks due to large annual mileage is higher than personal vehicles, however, such a fleet is easier to manage through a single control center. Vehicles of waste collection on gas engine fuel will reduce harmful emissions into the atmosphere and the noise level in the morning from the vehicles. Studies on the safety of vehicles on compressed natural gas have confirmed the high level of this vehicles, however, the issues of its reliability remain relevant. The proposed method for predicting potential failures and service planning, as well as forecasting operating conditions, will allow to take into account the prospects for expanding the gas engines vehicles’ fleet and ways to reduce the burden on the environment.

The main reason that hot turbulent jet ignition has become attractive to gas engine manufacturers is that hot jet ignition can achieve faster burn rates due to the ignition system producing multiple, distributed ignition sites, which has greater likelihood igniting a lean mixture compared to spark ignition. This leads to better thermal efficiency and low NOx production. Compared to conventional spark ignition, a hot jet has a much larger surface area leading to multiple ignition sites on its surface which can enhance the probability of successful ignition and cause faster flame propagation and heat release. Over the last few decades, pre-chamber jet ignition had technologically advanced from conceptual design phase to actual engines. The early designs developed by Gussak [1–4], Oppenheim [5, 6], Wolfhard [7], and Murase [8] showed the promise of lean ignition by a hot turbulent jet. Later, Ghoneim and Chen [9], Pitt [10], Yamaguchi [11], Elhsnawi [12], Sadanandan [13], Toulson [14, 15], Gholamisheeri [16], Attard [17], Perera [18], Carpio [19], Shah [20], Karimi [21], Thelen [22], and Biswas [23, 24] further investigated in detail the parametric effects and fundamental physics of turbulent jet ignition in laboratory scale prototype combustors and at engine-relevant conditions. All these studies support that turbulent jet ignition possesses several advantages over traditional spark ignition during ultra-lean combustion such as higher ignition probability, faster burn rates, and multiple ignition kernels.

In recent years gas engine manufacturers have faced stringent emission regulations on oxides of nitrogen (NOx) and unburned hydrocarbons (UHC) [1, 2]. Operating internal combustion engines at ultra-lean conditions can reduce NOx emissions and also improve thermal efficiency [3, 4]. An approach that can potentially solve the challenge of igniting ultra-lean mixtures is to use a reacting/reacted hot turbulent jet to ignite the ultra-lean mixture instead of a conventional electric spark [5–10]. The hot turbulent jet is produced by burning a small amount of stoichiometric or near-stoichiometric fuel/air mixture in a small volume separated from the main combustion chamber called the pre-chamber. The higher pressure resulting from pre-chamber combustion pushes combustion products into the main combustion chamber in the form of a hot reacting/reacted turbulent jet, which then ignites the ultra-lean mixture in the main combustion chamber. Compared to conventional spark ignition, the hot turbulent jet has a much larger surface area containing numerous ignition kernels over which ignition can occur. Hot jet ignition has the potential to enable the combustion system to operate near the fuel’s lean flammability limit, leading to ultralow emissions.

Three engine failures occurred from March to July in 2015. The failures were due to engine overloading and in each of the three instances caused severe scuffs and cracking on pistons and liners, particularly on #4 cylinders. Operating condition changes were identified as the root cause for the recent engine overload failures. Several maintenance issues, such as incorrect stepper motor settings, lubrication oil over filling and failed spark, also contributed to the failures. These factors combined and caused the engines to be overloaded and triggered the failure mechanisms which lead to the engine failures. To avoid failures in the future, the recommendations are provided, such as reduce the engine load by increasing the compressor clearance; monitor the engine load when operating condition changes and provide appropriate engine load awareness training to engineering and field personnel.