My article Why Tesla Must Get Back To Edison that was featured on LinkedIn Editor’s Picks attracted a lot of comments. I wish to thank every reader and commenter. While at first I wanted to answer each comment personally, I discovered that many comments required an extensive and very similar answer, therefore I decided to write this article.
Tesla vs. Edison
The previous article was not about the individuals, Nikola Tesla and Thomas Edison. They were both brilliant and very different. I haven’t met any of them personally, so I cannot really tell who was nicer or smarter 🙂 Both of them were visionaries, invented important stuff, made mistakes, and so on.
The article was about AC and DC, an issue which, in my opinion, requires immediate attention as this is not something to be fixed overnight.
Tesla, the company
In the title I was referring to Tesla, the company. I am a fan of Tesla and their work. Powerwall is the first public iteration and, while there are many aspects to improve, it’s the first time the worldwide media gave coverage to a battery that is supposed to improve the way we produce energy and store it. I know, this is not new, it has been done by so many other companies. Truth is that very few people take it seriously. If Tesla and Elon Musk will be advocating this cause, raising more awareness, everyone should use the momentum.
The power grid
First, just a background notice (not a disclaimer). I am a computer scientist and understand physics quite well, but I am not an energy engineer. This is just one of the reasons why I didn’t want to get into the details of the power grid in my previous article. A more important reason was that I do not think the power grid can be easily changed. I believe that it will be replaced at some point in time, but the revolution has to be triggered by masses.
However, since some of the comments suggested a wrong mindset, I will discuss a little about the grid. Change is difficult and many people are resistant to it, but without change we will not be able to turn green energy into a worldwide product.
Do not confuse physics with economics
Many commenters suggested that transporting DC in the grid is impossible or not efficient. Some did it quite aggressively. In fact, it’s more efficient to transport DC than AC, but economically it’s not feasible to do it because the AC power grid industry has a history of over 100 years with everything that comes along. Even so, high-voltage direct current is actually used in production simply because over long distances it’s physically impossible to transport AC. When it comes to DC, the only notable disadvantage is the equipment cost. Transformers are high-tech and expensive, and high voltage DC breakers are still a challenge, but it’s work in progress. That’s the essence of evolution, iterating and reducing the costs to make it attractive for large scale implementation.
It’s very rare for a new technology to be cheaper than the established one. If the cost is the only metric, then we should immediately kill green energy and continue to burn coal.
Fact: we rely on 100 year old architecture
It’s quite amazing that the architecture of the power grids we rely on has not changed much for the past 100 years. All DC skeptics immediately pointed out how easy it is to convert AC between different voltages. Indeed, it is easy, but also highly inefficient. The loss on the power grid between the electricity producer and the end-user is huge.
It’s funny that companies in the computer industry try to build datacenters with PUE (Power Usage Effectiveness) close to 1, or even electric cars, when a lot of energy right now is lost inside the power grid itself.
Many companies in the energy industry invested a lot in research to bring DC grids to reality. Such companies deserve our respect, even if they are not as popular as Tesla.
Is AC doomed?
There are applications where AC can do a better job with today’s technology. While DC motors have many advantages over AC motors, they are limited by the quality of the magnets built on their rotors. Furthermore, there is a limited supply of magnets on Earth, therefore power AC motors will not die anytime soon. For example, even Tesla uses an AC motor in their cars, even if the motor is connected to a DC power source.
Purists note – even brushless DC motors are driven by AC as they incorporate an inverter.
Green energy – the cloud phase
Supposing that we will be able to produce our own energy at home (using solar panels or any other technology), our contribution to the grid will become significant. I am very familiar with the cloud computing and the Internet model and I think that a similar model can be applied to energy distribution as well.
But it’s not only about our houses. Very few people look at an object and think about the energy spent building it. The industry as an energy consumer is actually more important than our house because it’s a massive polluter and eats much more energy than individuals. If we want to live on a better planet, minding only about our garden will not do.
In order to be able to produce energy and give it back to the grid, DC is a must. Technically, it will still be difficult to build such a network on a large scale, yet with a new grid architecture it should be possible. This is why I think that a grid redesign will be driven by end-users when they are able to produce excess energy.
Some commenters pointed out that there are standards for everything and that they are just waiting to be used. Well, a standard is useless without users. Personally, I could build a very efficient house, with DC circuits, highly efficient LEDs, fully automated and so on. I could even buy appliances with DC input, I could check the power efficiency for every electrical device I buy, but that’s not the way to do it. It does not help that my house is 90% efficient when our planet is dying.
So, you like AC and you think that it cannot be replaced by DC and it will never be. It’s your choice, but let’s use our imagination for a bit. Picture yourself on a spaceship, on your way to the newest human station built on another planet. If any, do you think that the sockets will provide AC?!