A solar plant including a solar field for production of steam, a turbine using steam, and an excess steam storage and draw off system. The system includes a latent heat thermal storage module and a liquid displacement thermal storage module including a liquid volume and a steam blanket. The modules are connected together so that the steam produced passes through the steam blanket before passing through the latent heat module, condensing, to be injected in the liquid volume, the lower part of the liquid volume being connected to the solar field and to an outlet of the turbine to let in or return cold liquid. The liquid volume acts as a liquid displacement reservoir.

A solar plant including a solar field for production of steam, a turbine using steam, and an excess steam storage and draw off system. The system includes a latent heat thermal storage module and a liquid displacement thermal storage module including a liquid volume and a steam blanket. The modules are connected together so that the steam produced passes through the steam blanket before passing through the latent heat module, condensing, to be injected in the liquid volume, the lower part of the liquid volume being connected to the solar field and to an outlet of the turbine to let in or return cold liquid. The liquid volume acts as a liquid displacement reservoir.

A method of controlling a thermal power plant for electricity generation, said power plant comprising at least one heat source to supply thermal energy to a working fluid circulation circuit. The circuit comprises a high pressure turbine mechanically connected to an electricity generator, a high pressure regulating valve controlling the steam supply to said high pressure turbine from a high pressure superheater associated with a high pressure storage tank. The fluid supply to said high pressure storage tank from a high pressure steam generator is controlled by a high pressure supply valve, and, in response to a need for additional electrical power, the opening of the high pressure regulating valve is increased the opening of the high pressure supply valve is reduced.

A method of controlling a thermal power plant for electricity generation, said power plant comprising at least one heat source to supply thermal energy to a working fluid circulation circuit. The circuit comprises a high pressure turbine mechanically connected to an electricity generator, a high pressure regulating valve controlling the steam supply to said high pressure turbine from a high pressure superheater associated with a high pressure storage tank. The fluid supply to said high pressure storage tank from a high pressure steam generator is controlled by a high pressure supply valve, and, in response to a need for additional electrical power, the opening of the high pressure regulating valve is increased the opening of the high pressure supply valve is reduced.

Techniques for subsurface thermal energy storage of heat generated by concentrating solar power enable smoothing of available energy with respect to daily and/or seasonal variation. Solar thermal collectors produce saturated steam that is injected into a producing or wholly/partially depleted oil reservoir that operates as a heat storage reservoir. Some of the saturated steam generated by the collectors is optionally used to generate electricity. Heat is withdrawn from the reservoir as saturated steam and is used to operate an active thermal recovery project (such as a producing thermally enhanced oil reservoir) and/or to generate electricity. Withdrawn heat is optionally augmented by heat produced by firing natural gas. The reservoir is optionally one that has been used for thermally enhanced oil recovery and thus is already warm, minimizing heat losses.

A power plant comprises: (a) a liquid pressurizing unit, (b) a Pelton turbine having a rotating shaft, (c) a duct connecting the pressurizing unit to the Pelton turbine for supplying pressurized liquid to the Pelton turbine, the duct being provided with at least one injector, and (d) a generator, advantageously an alternator, capable of being driven directly by the rotating shaft of the turbine, advantageously with the interposition of a gear system.

A power plant comprises: (a) a liquid pressurizing unit, (b) a Pelton turbine having a rotating shaft, (c) a duct connecting the pressurizing unit to the Pelton turbine for supplying pressurized liquid to the Pelton turbine, the duct being provided with at least one injector, and (d) a generator, advantageously an alternator, capable of being driven directly by the rotating shaft of the turbine, advantageously with the interposition of a gear system.