Energy in the 21st Century—Where Will It Come From?
In my last article on Sustainability and Innovation, I outlined the points to consider when we want to use our earth in a sustainable way. In this article, we take a closer look at where the energy for this new, sustainable world will come from.
There are certain things everyone should agree on, such as the fact that coal is not the most sustainable source of energy we have at our disposal. It is also not the most eco-friendly way to heat our houses or to move around in our cars (yes, that’s a thing!). Since poverty levels are decreasing generally all over the world with more and more people getting access to technology, the global demand for energy is constantly increasing. The big question is: how can we cover our increased demand for energy?
Renewable Energy—the Solution, but When?
The best route to go is renewable energy: solar energy, wind power, hydro power, bio energy, hydrogen and fuel cells, geothermal power, and other forms of energy such as energy from tides, the oceans, and hot hydrogen fusion. Prior to the development of coal in the mid 19th century, nearly all energy used was renewable. Humans used biomass to light up fires as far as 400,000 years ago, we sailed the seas with the power of wind, and we used water power to crush grains. However, there is a certain disadvantage with renewable energy sources: storage capacity.
With the introduction of fossil fuels, mankind was able for the first time to make large amounts of transportable energy available according to demand. For flourishing societies, this was an unbeatable advantage over complicated technologies such as hydroelectric power, and we are still far from talking about solar energy in the 19th century. I am not getting into what the use of fossil fuels meant for the environment, since today everyone should be aware of its effects on our planet. What we should be focusing on right now is how we can drive change with the technologies that are available already.
Pioneers in Sustainable Energy
Austria has pledged to get all its power from renewable energy sources by the year 2030. At the moment, the alpine state obtains 76% of its energy from renewable sources, most of it from hydropower, but wind and solar power are also growing strongly. Of course, there are countries like Iceland that are already one step ahead, with 100% of their energy demand being generated from renewable energy sources. Other countries such as Denmark, Costa Rica, Nicaragua, and Sweden are also on the way to 100%. Although the path is sometimes rocky, you still have to walk it if you want success in the long run.
However, the expansion of power plants for green energy alone is not enough. Time after time, grid operators have to compensate for imbalances in electricity consumption and switch on conventional power plants in order to cope with consumption peaks and prevent total blackouts. The problem is that the sun usually doesn’t shine exactly when the most electricity is needed, or that there is no wind when the whole country is watching football on TV. Gas power plants, for example, have to supply electricity as needed, which drives up costs and results in strong fluctuations in prices on the electricity market.
Storing Energy in Batteries
The biggest problem is how to store energy that is produced in a green and sustainable way. Of course, the storage of energy in batteries is obvious. Solar systems on the roof of a family home can feed a battery in the basement, which can be used as needed. Depending on the size of the solar panels and battery as well as the average hours of sunshine at a given location, the energy consumption of a typical household could even by covered completely off grid.
So, which kind of batteries are we talking about? There are different types of batteries, lead batteries, lithium-ion batteries, which are used in smartphones and e-cars, as well as Redox-Flow-batteries, which are used for primarily stationary applications like wind power plants. But there is a problem with batteries, prices will rise when demand for them does. Since batteries depend on rare raw materials, they are also a precious good and rather unsuitable for mass production in a way that would be needed to power an entire society.
Nevertheless, there are some providers who have set themselves the goal of supplying the market with such batteries and creating a more or less decentralized power grid. Pioneers in this field are definitely companies such as TESLA, but also Austrian companies such as Kreisel and the startup SolMate. The latter has proven its worth with its innovative system that helps you produce your own energy through solar panels, storing it in a battery and provides this only to your apartment when needed. This way, up to 25% of your own energy demand can be covered.
Large Scale Energy Storages to Power Societies
One other way to do it, at least in countries with great height differences, is through pumped storage power stations. In these power plants, water is pumped upwards with cheap surplus electricity at times of high productivity and then lowered again to drive pumps that produce cheap hydropower when, for example, no solar electricity is available. However, the possibilities for the construction of such power plants are largely exhausted, at least in Europe.
Scientists at TU Graz just came up with a new way to solve this problem. A team headed by Franz Georg Pikl, a PhD student at the Institute of Hydraulic Engineering and Water Resources Management, has combined the advantages of pumped storage technology and heat storage using water as a medium to create a “hot-water pumped storage hydropower plant”. The new system stores and supplies electricity as well as heat and cooling energy as required.
In short, the entire system is relocated underground and combined as a thermal energy storage unit. You can read everything about the award winning system on the TU Graz website.
This is not the only possible combination of sectors that the future might hold. „Power-to-Gas„-technology is something scientists are also experimenting on and starting to have major successes with. With this technology, methane can be generated with the use of electricity and then be stored in conventional gas networks and passed on to users. It can also be converted back into electricity at any time – be it decentralized in small gas turbines or centralized in gas power plants. The storage capacity of green energy in that scenario would be many times higher than that of batteries, for example. Another advantage is that there is the possibility of seasonal storage, for example from summer to winter.
Another very advantageous thing is that in order to produce methane you need CO2, which can be either recycled from fumes, or produced in biomass power plants and is therefore climate-neutral. As of now, this technology is still very expensive, but given the speed at which technologies develop there is a good chance that prices will fall and since oil and gas won’t get cheaper in the future the outlook is extremely positive.
The energy market is extremely complicated and there are de facto no simple solutions that can be implemented overnight. But what we can do is not close our eyes because the road may not be easy, but accept the challenge and grow with it. We have no other choice.