A thermal storage subsystem may include at least a first storage reservoir configured to contain a thermal storage liquid at a storage pressure that is greater than atmospheric pressure. A liquid passage may have an inlet connectable to a thermal storage liquid source and configured to convey the thermal storage liquid to the liquid reservoir. A first heat exchanger may be provided in the liquid inlet passage and may be in fluid communication between the first compression stage and the accumulator, whereby thermal energy can be transferred from a compressed gas stream exiting a gas compressor/expander subsystem to the thermal storage liquid.

In an energy time-shifting process, an electrical grid is monitored. Based on monitoring the electrical grid, it is determined that one or more criteria are satisfied at a first time. In response to determining that the one or more criteria are satisfied at the first time, water is directed from an aquifer located at a first elevation to a reservoir located at a second elevation. The first elevation is lower than the second elevation. Subsequent to directing the water from the aquifer to the reservoir, water is directed from the reservoir to a turbine generator located at a third elevation. The third elevation is lower than the second elevation and higher than the first elevation. Electrical power is generated using the turbine generated based on the water flowing through the turbine generator. Water is directed from the turbine generator into the aquifer.

Operating coal fired energy systems. A method of operating a coal fired energy system comprises operating a coal fired steam generator comprising a coal feed system and a main air feed system to provide a coal-air mixture as a heating source for a boiler for generating steam. The method includes operating an auxiliary air compression system comprising a fueled engine coupled to a compressor for providing an auxiliary supply of compressed air to a soot blower of the coal-fired steam generator. The method comprises injecting the auxiliary supply of compressed air along walls of the boiler to remove soot and ash buildup from the boiler.

A hydraulic compressed air energy storage system includes air and liquid tanks, each of which includes interdependent volumes of liquid and air. Each tank includes dedicated passages through which incoming air may be fed, forcing outflow of liquid, or incoming liquid may be fed, forcing outflow of air. Compressed air tanks are connected to a first group of the air and liquid tanks. The system further includes a pump and a liquid turbine, the liquid turbine being electrically connected to a generator for generating electric power. During charging of the system, liquid is pumped through the first group of air and liquid tanks, and air is expelled from the first group of air and liquid tanks and compressed in the compressed air tanks. During discharging of the system, compressed air is released from the compressed air tanks, and said compressed air pumps liquid through the liquid turbine, thereby generating electricity.

A gyroscopic roll stabilizer for a boat includes an enclosure mounted to a gimbal for rotation about a gimbal axis and configured to maintain a below-ambient pressure, and a flywheel assembly including a flywheel and flywheel shaft, with the flywheel assembly rotatably mounted inside the enclosure for rotation about a flywheel axis. The gyroscopic roll stabilizer also includes a motor operative to rotate the flywheel assembly and disposed inside the enclosure. A motor cooling circuit is configured to transfer heat away from the motor. The motor cooling circuit has a closed fluid pathway for recirculating cooling fluid therein. The fluid pathway includes a fluid channel jointly defined by the motor and the enclosure and having the cooling fluid therein. The gyroscopic roll stabilizer is configured to transfer heat away from the motor to the cooling fluid. Related methods are also disclosed.

A stacked lamination endplate for a rotor that includes a number of adjacent laminations, stacked one on top of another, wherein each lamination has an identical shape, the shape having a central region, symmetric about a center axis, and a number of spokes, each spoke emanating radially outward from the central region, where each spoke includes a through-hole at its distal end, and wherein the laminations are stacked one on top of another and aligned, enabling, for each spoke, a bolt to be inserted through a corresponding through-hole of each lamination.

In an embodiment, a gas turbine system is provided. The gas turbine system may include a supplementary air system and a flow diffuser configured to receive compressed air from the supplementary air system. The gas turbine system further comprises a gas turbine compressor downstream the flow diffuser, a combustor downstream the gas turbine compressor, a turbine downstream the combustor, and a turbine haft. The turbine shaft comprises a thrust bearing and a clutch. When the gas turbine system is operating, the gas turbine compressor does not consume electricity.

A station constituted of: a control circuit; a first and a second bi-directional converter, each in communication with the control circuit, each arranged to be coupled to a respective plug-in electrical vehicle at a respective first port thereof; and a connection to an AC grid, wherein the control circuit is arranged to: draw electrical energy from a first plug-in electrical vehicle coupled to the first port of the first bi-directional converter; and provide at least some of the drawn electrical energy to a second plug-in electrical vehicle coupled to the first port of the second bi-directional converter.

Systems and methods may use a low speed controller in addition to an economic optimizer to achieve long-term objectives without significantly disrupting or destabilizing an electrical system. Specific long-term objectives include maximizing a capacity factor incentive and regulating battery degradation, but the methods and systems herein can be extended to more long-term objectives. A low speed controller can adjust one or more parameters of a cost function based on the relation between the projected state of the electrical system and the one or more parameters to effectuate a change to the electrical system to attempt to comply with the long-term objective.

An electric magnetic resistance control structure for an exercise machine includes a base; a flywheel, pivotally connected to the base through a rotating shaft, the rotating shaft defining an axial direction, the flywheel, a non-magnetically sensitive layer being coupled to a circumference of the flywheel; a power unit, fixed to the base; a magnetic resistance unit, including a coupling portion corresponding to an arc of the non-magnetically sensitive layer, at least one magnetic member being provided on the coupling portion and kept at a distance from the non-magnetically sensitive layer to generate a magnetic resistance effect; a control unit, configured to control a current applied to the power unit to drive the magnetic resistance unit to move along the axial direction, thereby changing an overlapping area of the magnetic member and the non-magnetically sensitive layer in the axial direction, so as to adjust a magnetic resistance of the flywheel.