About Renewable Energy
Energy and Evolution
Since we started using our brain more than our muscles our species was always a step ahead of the others but this gap widened when we learned to master energy and it all started when we learned how to produce fire. Since then it was a slow but steady improvement but we had to wait few thousand years before seeing man using energy to actually create things, I am talking about the discovery of steam power and the industrial revolution. Machines could do the work of many men and produce things in a much faster way. But that wasn’t enough, the flywheel of progress had only just started and soon lead to another discovery. The use of fossil fuels to move things and most of all to move men. The world became a much smaller place when we invented cars and planes. But our civilization has not reached its full potential yet and its growth is urging us to find even more energy to propel our progress.
Environmental Issues
But all this comes to a cost, by burning fossil fuels we are poisoning ourselves and our planet. In fact we are constantly producing CO2 and other gasses that act as a greenhouse to the atmosphere. These gasses let solar radiation through the atmosphere trapping heat. This process sustained life for milions of years as a warm planet is better than a frozen one and nature has its own ways to control the levels of CO2 to assure right amount of heat. But we are disrupting this equilibrium by cutting down trees and producing more CO2. As a consequence to this increase heat, the ice started melting at the poles (I mean melting in a faster way than it used to) and the level of the sea started rising. Just imagine if in few years Venice would be completely underwater and all the species that actually live at the poles exterminated because their habitat was destroyed. We all know that we must find alternative ways to obtain energy and the longer we wait the more difficult will be to fix the mess we are creating. Unfortunately when is about future generations and environmental problems we have the tendency to look at the very short term and tell ourselves that somebody else will cope with these problems, our sons.
Renewable Green Energy
The alternatives we have today are included in what we call “Renewable Green Energy”. After few nuclear disasters we started investing some money in trying to find out alternative and renewable ways to produce energy but the bigger limitation to this is actually the renewable side of it. In fact something that is plenty and cheap is not very lucrative, thus big investors prefer to invest their money in more profitable ways. As Nikola Tesla realized much earlier than many, our planet is plenty of energy and in many forms.
Energy from air and water
The very air we breathe carries an incredible amount of it. In fact, when air moves from zones having different pressures carries kinetic energy that we know as wind. Today we are able to capture only a small fraction of this energy by using eolic turbines. To be efficient they need to be big and also as far as possible from the surface. For this reason a much better and efficient way to capture wind energy is to use kite wind generators. A similar concept can be applied to water. Ocean waves carry huge amount of energy and we invented machines called pelamis able to convert wave energy into electricity. They in fact, flexes and bend as the wave pass and generate energy in the process.
Capturing Energy from the Sun
But nature itself is constantly capturing energy from the sun. Plants have been doing this for milions of years and burning biomasses was probably the very first form of energy the man used. Today we can obtain energy from biomasses in mainly 2 ways, heat by combustion of plant-derived material or production of biofuel from crops. Unfortunately there are many issues associated with biomasses. First of all this is the least green of the renewable energies as it produces significant amount of CO2 emissions. Moreover, it leads to another problem which is speculative de-forestation. Although teoretically is very sound, even biofuels have their own issues, in fact they require usage of vast amount of land that cannot be used for the production of food. Just look at poor countries where people cannot feed their families because crops are used to produce ethanol.The most symbolic of all forms of renewable energy is solar power. It relies on the use of solar panels for the conversion of sunlight into electricity. Although those panels are becoming cheaper they are still very expensive and paradoxically they require a huge amount of energy to be built, requiring many years of usage before producing the same amount of energy that was spent in their production.
Limitations of Renewable Energy
But the bigger limitation to all forms of alternative energies we know is supply. Our growing civilization requires huge amounts of energy at every time of the day and night. Therefore it would be unthinkable to rely only on solar energy as it would not produce significant amount of energy in night time and wind turbines would produce energy effectively only during windy days. Even by combining all kinds of renewable energies together we may not produce enough energy to meet the demand of our energy-thirsty society. Moreover, it needs to be said that today we are not using these energy sources properly. For example most people that decide to install solar panels on the roof of their houses often do so not on the sun-exposed side of the house of on the street-exposed side, that’s because showing off to their neighbours is more important than produce energy efficiently. Or another example is in Japan, where a small eolic turbine was build on the roof of a big building in the middle of a city, now imagine how much wind there could be in the middle of a city. As you can imagine, this turbine was generating almost no energy (and after few years to not look stupid they decided to apply a small engine to make this turbine run, so in fact it was consuming energy instead of producing it).
Interesting Documentary about Hydrogen
Hydrogen, the Future
In my opinion until renewable energy will be used only to win political battles or to make our neighbours jealous it won’t get much further than this but afterall I think its future could still be very bright. In fact there is another source of energy that I didn’t mention before and that has incredible potential, Hydrogen.
Obtaining energy from hydrogen is relatively simple and it can be done in a massive scale (just imagine that hydrogen is the fuel that stars are burning and that makes them shine). By electrochemically combining hydrogen and oxygen in a process that do not produce CO2 but pure water instead, we can obtain huge amount of energy. Generally, one of the problems associated with energy is that it cannot be stored but hydrogen as a gas can be easily and cheaply be stored and transported to long distances. Moreover, this electrochemical process do not require big reactors and it could happen even in small devices such as a mobile phone. But why then we don’t use it?Well there are many reasons but the biggest one is that our politicians are ignorant, thus easily deceived by “experts” that think we are not ready yet to use this cheap form of energy. On the other hand why use hydrogen when fossil fuel is still much more lucrative?