A Lesson from the Wind and the Sun

lanka 2019-11-22 06:54:35

Everyone loves a good story. Some of the greatest stories of all time come from Aesop’s Fables. Aesop (620–564 BC) was a Greek slave, fabulist, and storyteller who receives credit for collecting a variety of tales that illustrate moral lessons. One of his most famous ones is The North Wind and the Sun.

The North Wind and the Sun were disputing which was the stronger when a traveler came along wrapped in a warm cloak. The North Wind and the Sun agreed that the one who first succeeded in making the traveler take his cloak off should be considered stronger than the other. Then the North Wind blew as hard as he could, but the more he blew, the more closely did the traveler fold his cloak around him; and at last, the North Wind gave up the attempt. Then the Sun shined out warmly, and immediately the traveler took off his cloak. And so, the North Wind was obliged to confess that the Sun was the stronger of the two.

The fable makes the point about the superiority of persuasion over force. Most people see that the point of the fable is not that the sun is more powerful than the wind. They each are mighty in their distinct ways.

In Texas, I often experience blisteringly hot summer days climbing over 40˚C. At other times, Texas has powerful winds as manifested by the >100km wind that caused significant damage to the tree in my front yard (Figure 1).

Figure 1: An image of my tree wounded by the wind. (Source: Joey Golata)

Like the fable, I hope to use the power of persuasion over force to talk to you about the potential for both solar and wind energy. Because both of these forces are so powerful, it is beneficial for humans to harness their power.

Worldwide energy consumption is expressed in units of megawatt hours (MWh). Global energy consumption is estimated at >60 million daily MWh of electricity and approximately another 240 million daily MWh more in various other forms (i.e., coal, gas, hydro, nuclear, etc.). The combination of these different forms of energy brings total global energy consumption to around 300 million daily MWh.

Interestingly both wind and solar energy sources have enough potential energy generation capacity to completely meet the world’s daily MWh needs. Wind’s potential energy generation capacity is estimated at 480 million daily MWh (≈480/300, >150 percent). Solar’s potential energy generation capacity is estimated at 400 million daily MWh (≈400/300, >130 percent).

While there is plenty of potential, there is not yet as high of the utilization of these forms of energy. Higher utilization is primarily an issue of developing cost-effective, reliable, safe, and robust energy capture and conversion systems to make it more feasible and practical.

Harnessing this power is a job for Energy Storage Systems (ESS). ESS allows solar and wind power to better integrate with the grid. Energy storage is a critical element for leveraging intermittent renewable and distributed generation technologies. Analog Devices (ADI) offers a wide range of signal chain solutions for battery management systems (BMS), charging, and power conversion. ADI’s product portfolio includes Battery Management Systems Integrated Circuits (ICs) for the monitoring of high or low numbers of cells, together with isolated SPI communication channels as well as future wireless implementations. For high-voltage power converters used to charge/discharge the batteries or to spin flywheels, ADI provides both the ICs and system-level reference designs, focusing on the innovative isolated gate drivers for silicon carbide (SiC) and gallium nitride (GaN) power switches, high-efficiency power management ICs and modules, and isolated communication interfaces.

I hoped you enjoyed the wisdom shared in this story. It is a story that you and I will write for our future. The power of the wind and sun is all around us, a gift for us to enjoy. I hope I have persuaded you that it may be in our best efforts to seek ways to harness their abundant power for the flourishing of humankind. Energy storage systems will be necessary parts of any such solutions. It is no fable, ADI is leading the way in harnessing and giving you the power of the wind and sun.