The irregularity of two of the large renewable energies, solar and wind, makes it necessary to create energy storage systems that help stabilize the supply, but some projects have stalled due to a bureaucratic obstacle: according to the legislation we have too much energy.
A power station without a plug. The project for the creation of a reversible hydroelectric power station in Estercuel (Teruel) has run into an unsuspected pothole, as denounced by the company responsible for the project, Atalaya: that we produce too much energy.
The project currently has a good part of the infrastructure built (it takes advantage of an existing water reservoir) and has environmental approval from the Aragonese Institute for Environmental Management (INAGA). Even so, the future plant faces a blockade since, explains the company, it has connection points to the electrical network.
A strategic technology. Pumped or reversible hydroelectric plants are power plants that simultaneously fulfill the function of gravitational batteries: mechanisms capable of storing electrical energy thanks to gravity. These power plants are the most efficient batteries we have when it comes to storing excess energy from non-regulable energies such as solar and wind.
The mechanics of reversible centrals is simple. These stations have two water tanks located at two different heights. When there is excess energy, it is used to drive a pump that moves the water from the lower tank to the upper one.
When the energy demand increases, the gates open and the water from the upper tank is channeled to the lower one. Along the way, it drives a turbine that returns energy to the electricity grid. Pumping stations are not only the only gravity battery designs but they are the most widespread option.
The Estercuel power station. In the case of the Turolense power plant, the project reconditions the facilities of the old Estercuel open-cast coal mine to serve as a lower deposit of the system. Pond that already contains enough water to power the plant, that is, it would only require water to compensate for its evaporation.
As the company explains, the already existing pond is located at 732 meters, and would be complemented by a deposit higher than 1,030 meters of altitude and by the relevant pumping and generation system.
A Kafkaesque tangle. The connection problem is mainly that the Estercuel station is, for bureaucratic purposes, an electricity generation plant and not a storage one. This implies, denounces the company, a bureaucratic obstacle when considering that the network.
There is a paradox that is what gives a Kafkaesque dimension. The problem is that the network already has an excess of energy sources that could block it during peak generation hours. But it is precisely at these production peaks when plants such as those in Estercuel absorb this excess supply. These plants not only do not saturate the network but help to regulate and stabilize it.
The complaint by Atalaya comes from afar. Already in February, the employers’ association of companies in the energy storage sector, ASEALEN, urged the Ministry for the Ecological Transition and the Demographic Challenge to reverse this situation of blockade.
In Xataka | Renewables have a very valuable ally, and it is not hydroelectric pumping, nor batteries, nor hydrogen: it is compressed air