Introduction to Renewable Energy

In today's world electrical energy supply is needed for almost all tasks and activities. Everyday activities such as making morning coffee are associated with electricity consumption that we don’t even think about. As the population and living standard around the world grows steadily, so does the demand for appliances and services that need energy. Thus, we can expect growth in global energy consumption. This growth can be reduced by optimizing processes and reducing the development of more economical devices. However, saving significant contribute to lower energy demand, but we need to focus especially on energy resources in particular.

Coal and oil were key energy sources during the first and second industrial revolutions, paving the way for the modern world with rapid development. The link between the amount of CO2 emitted and the global average temperature is hard to deny. There is already many technological solutions in the field of renewable energy, but still many challenges to get rid of CO2 emissions and move to a carbon-neutral society. Our common goal must be to invest in science and to arouse interest in young people in scientific and technical fields. Both today's and future generations of scientists and engineers will need to work together to find solutions to lead our world into a brighter and cleaner future.

Center eksperimentov Maribor conducts a number of workshops in the field of renewable energy sources - from lectures to practical presentations with models. Offering a wide range of workshops for primary and secondary schools with the aim of bringing this complex and current field closer to young people in an understandable way.

An important challenge associated with the transition to renewables is the storage of this energy for periods when energy consumption is higher. Solar and wind energy are rather volatile sources, so we have to bridge the parts of the day when they do not provide us with enough energy. Energy can be stored in many ways. Among the most widespread are pumped storage hydroelectric power plants, large storages of lithium batteries, and hydrogen fuel cells are also gaining ground. At the Maribor Experiment Center, we pay a lot of attention to this technology, which has great potential for the future.

Oil extraction is becoming more expensive from year to year, so alternative energy sources are increasingly affordable. Due to the already mentioned greenhouse gas emissions from the burning of fossil fuels, hydrogen gas has been an interesting alternative energy source for many years and is one of the fuels of the future. It has many environmentally friendly properties and even some advantages over fossil fuels. When hydrogen burns with oxygen, only water is formed. Hydrogen has a high specific energy density, is non-toxic and does not cause corrosion. It is the lightest and most represented element in the universe is colorless, odorless, and tasteless. It is contained in water, organic compounds and all living organisms. The problem is that it is very difficult to release it from them.

Most hydrogen today is still obtained from fossil fuels. Another way of obtaining hydrogen is by electrolysis of water, in which water is split into hydrogen and oxygen. Electrolysis is a phenomenon when an electric current flows through a liquid, which causes the secretion of substances on the electrodes. Recently, the extraction of hydrogen with microorganisms has become more promising. Some cyanobacteria and algae form hydrogen as a by-product when performing their own processes. They contain hydrogenase enzymes that start producing hydrogen under certain special conditions.

In addition to the most widespread and well-known way of storing electricity in batteries, there also known other ways of storing and converting energy. Hydrogen fuel cell technology, which converts fuel directly into electricity, is the most promising, reliable and rapidly evolving technology. A fuel cell is an electrochemical device that converts the chemical energy of a fuel with oxygen molecules (oxidant) into electricity. In a simple fuel cell, a platinum catalyst at the anode splits hydrogen gas into electrons (e-) and protons (H+). Electrons drive an electric current through a wire. Hydrogen ions (protons) migrate to the cathode, where they combine with oxygen and electrons to form water. In addition to electricity, heat is also released.

Today, there are several well-known car brands that offer and develop commercially available models of fuel cell cars. Through its subsidy and green mobility promotion programs, the European Union is accelerating funding for the construction of hydrogen-powered car pump infrastructure. Hydrogen fuel cell electric cars offer faster charging and longer range than lithium battery cars.

In the future, the Center eksperimentov Maribor will further increase the scope of workshops and enrich our collection of experiments so that young people can test and control miniature power plants on certain energy sources and use them to run a small town.