According to the United Nations, the world population is expected to reach 8.5 billion from an estimated 7.7 billion in 2019. This means that key resources like energy, food, and water are expected to become dearer. Unless we move towards sustainable energy solutions, an energy crisis is looming large.
While there is no short-term panacea, researchers are working on various technologies that could help power our future energy needs. If these technologies come through, it will help fill the energy need-gaps better while also being eco-friendly.
Let’s take a quick look at some of the out-of-the-box energy solutions that go beyond traditional energy sources, based on insights.
Georgia Tech is working on a technology that generates electricity by the isothermal expansion of solar heat and sodium. It is called Na-TECC – combining Sodium’s chemical symbol with the initials from ‘Thermo-Electrical-Chemical Converter’ and has no moving parts as a conversion engine.
A sodium redox reaction is thermally driven on opposite sides of an electrolyte to generate electricity. Due to an electrochemical potential produced by a pressure gradient, the solid electrolyte passes the resulting positive electric charge; electric power is extracted when electrons travel to an external load. The end goal of this process is to acquire a heat-to-energy conversion of 45 percent, which is far better than most conventional energy sources.
Thermoelectric generators (TEGs) are usually made from inorganic semiconductors and are solid state devices that do not need moving parts to convert heat to electricity. Due to their low thermal conductivity and flexibility, polymers are considered attractive materials for use in TEGs. The use of polymers leads to innovative designs for high performance devices sans active cooling with significantly lowered production costs.
An example of this is Air Force Office of Scientific Research funded project that has developed a radial TEG that can use waste heat to generate electricity and can be wrapped around any hot water pipe. There are many use-cases for such generators: powering light sources, components or wireless sensor networks that analyse air quality and temperature apart other physical or environmental conditions.
Developments in flexible TEGs open up opportunities in wearables or various Internet of Things devices that have a combined estimated worth of over 1 trillion USD, at the time of writing.
Recycling Radio Waves
To collect ambient energy from the radio frequency (RF) spectrum, an electromagnetic energy harvester has been developed by researchers led by Manos Tentzeris: Potential use case is for operating upcoming IOT devices, smart city sensors, and wearable devices.
The idea behind harvesting radio waves isn’t new but endeavours, until recently, were limited to short-range systems that were very close to the energy source. The energy harvesting solution by Tentzeris is the first long range one that can harvest energy from a 7-mile distance.
The commercialization of this technology could happen in just 2 years’ time.
A decarbonized future
According to an IEA report, estimates that 90 percent of the new energy generation in 2020 happened via alternate energy sources, and only 10% was powered by gas and coal. Today, alternate energy source installation like solar power are becoming much cheaper than conventional fossil-fuel based sources that were the dominant source of power for more than 5 decades.
There is a heightened awareness in the new normal about sustainable energy sources. The deployment of alternate energy solutions could get accelerated by new global energy policies. According to the IEA, India and the European Union shall drive the global change towards renewable energy in 2021.
Alternate energy sources are expected to play a critical role in developing an agile and sustainable tomorrow.