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Minoan Energy Community focuses also on the most advanced technologies regarding electricity production from renewable energy sources. Solar Power Tower plants (SPT) features as, perhaps, the most promising of them. The operation of a Solar Power Tower plant is based on a field of highly reflective flat surfaces, called heliostats, placed on ground and around a tower, at the top of which a solar receiver is placed. The heliostats are sited and oriented with regard to the solar tower, so as the reflected solar radiation is concentrated at the solar receiver, where it is transferred to a working fluid (liquid or gas) in the form of heat. The fluid transfers the absorbed heat to a power block, where it is utilized to produce electricity through a conventional thermal generator. A heat storage facility, based on molten salts, can be also introduced in the plant, to expand its operation during night-time.

So far, the developed and constructed SPT plants belong to the so-called 2nd generation plants, which operate with working fluid’s temperature up to 560 οC at the receiver and a typical steam thermodynamic cycle (Rankine cycle), implemented with a steam turbine. The total solar – electric efficiency of a 2nd generation plant normally ranges between 10% and 20%. For a 50 MW SPT plant, a typical final electricity production specific cost can be achieved close to 0.18 – 0.20 €/kWh.

Minoan Energy Community focuses on the 3rd generation SPT plants. This new emerging technology, with a combination of advanced composite ceramics materials in the receiver, the heliostats and the heat storage tanks, the use of appropriate working fluids and the introduction of a Brayton thermodynamic cycle, implemented in one or more gas turbines, can increase the working fluid’s temperature at the receiver above 700 οC and the overall solar – electric efficiency of the SPT plant at 30%. The achieved electricity production specific cost drops at 0.12 €/kWh. This low production cost, combined with the secure and guaranteed power production during the whole daily period, makes the SPT technology as one of the most promising technologies regarding energy transition.

Minoan Energy Community participates in a group of top-level scientists worldwide on the field, to develop an advanced 3rd generation SPT plant. The size of the plant will be defined, among others, by the available for installation land, a crucial issue not investigated so far.

Pumped Hydro Storage (PHS), as it is in general accepted, constitutes the most technically mature and economically competitive electricity storage technology. The operation concept is simple and it is practically based on the electricity storage in the form of mechanical energy (potential gravitational energy), with water as the working fluid. Practically it is implemented with two water reservoirs located in sites with different absolute altitudes between them, connected to each other with pipelines. When there is the need for electricity storage, electrically powered pumps are supplied with the electricity surplus and water is lifted from the lower to the upper reservoir. When there is the need for power injection in the electrical grid, the stored water is released from the upper reservoir and through the pipelines it is led to a hydro power plant, where electricity is produced by hydro turbines. Until today, 85 GW of PHS plants have been constructed and operate, while, until 2030, additional 105 GW are expected to have been integrated.

Crete constitutes an ideal geographical space for the development of PHS plants. A highly favourable location is found at the Eastern Messara valley in the Prefecture of Heraklion, where the available land terrain morphology at the stream of “Anapodari” offers an ideal location for the construction of a gravity dam and the configuration of the lower reservoir of the PHS plant. Depending on the dam’s height, the achieved lower reservoir’s storage capacity can exceed 20 million cubic meters, which, in parallel with the PHS plant, can also be used to serve the irrigation needs of the area. The upper reservoir can be constructed in one of the neighbouring tops at the Eastern Asterousia mountain. According to the first preliminary calculations, the nominal capacity of the specific PHS plant can exceed 50 MW, with a set-up cost at the range of 150,000,000 euros.

Minoan Energy Community has establish a close communication with the Regional Authority of Crete, the hosting Municipality of Minoan Pediadas as well as the neighbouring Municipalities of Viannos and Archanon - Asteroysion, for the beginning of the study and the licensing of the project.