It’s always lovely to come home in the evening, maybe after a long day of study or work, knowing that with the flick of a switch we have all the power we need at our fingertips, as well as being able to use any number of electrical appliances and devices (including the PC or smartphone that you’re using right now to read this article). These are such automatic actions that we now take them completely for granted: but we should never forget that all this is possible thanks to the existence of a perfect “assembly line”, which from production to delivery, through distribution via the power grid, brings electricity to our homes 24 hours a day, 365 days a year. The production of electricity It all begins with production, which comes about by converting energy generated by a primary energy source into electricity. This source can be non-renewable (like oil, coal, natural gas or nuclear fuel), or renewable, like solar, wind, hydroelectric or geothermal energy. In all cases, electricity is generated inside an electric power plant, from which it is then transferred to us consumers via the power grid. The functioning of the grid is all about balance: there must always be balance between the energy supplied by the power plant and the consumer demand for energy. Let’s think about a two-plate weighing scale, where the plates must always remain at the same height: it’s the system of distribution and transmission that ensures this balance, and which extends around the world thanks to billions of kilometers of high-voltage power lines all over the planet. How to conserve electricity A key feature of the distribution of electric energy is that we consume electricity as soon as it’s produced by power plants: in other words, energy is consumed “fresh” (a bit like milk). But couldn’t it be stored and conserved instead, so that it could be used later, in the future? Of course it can! Today this is done mainly by using lithium and flow batteries, but systems for pumping water to hydroelectric power plants on a continuous cycle are also being used. Also being tested are thermal energy storage systems (TES, which for example use simple stones to store heat, which is then transformed into steam that powers an electric turbine), new batteries with alternative chemical components rather than lithium, and systems for gravitational energy storage or gas compression storage. A really important boost for the development of these storage systems comes from renewable energy: in this case, it’s crucial to be able to store solar and wind energy (which can only be generated at certain times of day) in order to make it available 24 hours a day. From a sustainability perspective, this outcome guarantees greater efficiency, lowers costs and lets us ‘recycle’ energy that would otherwise be lost. It also facilitates the gradual process of electrification, which means switching to the use of electricity produced from renewable sources for the operation of businesses and services that, until recently, were powered by fossil fuels. Future forecasts are very encouraging: according to the latest report from IRENA (International Renewable Energy Agency), the amount of electric energy available in storage systems is set to triple between 2017 and 2030 – resulting in great benefits for everyone.
