How to Drive an Electric Toothbrush

Question: What are the implications for the electric grid when it comes to implementing these large-scale systems?

Bill Mitchell: One of the problems in transforming any kind of large-scale system is what I like to think of, let’s call horseless carriage thinking. Even the term sort of suggests to you what I’m talking about here. So, when the horseless carriage replaced the horse and carriage, essentially it was a kind of substitution, you take out the horse and put in an internal combustion engine. And then the way people tended to think about electric automobiles as you take out the internal combustion engine and you stick in a hybrid power train, or you stick in a battery electric system. And I think you have to step back and say, no, the real potential is to fundamentally rethink the way things work. So part of the fundamental rethinking that I think is necessary with electric vehicles is to get away from the old idea that you fill a vehicle up with fairly large amount of energy and drive it around for quite a long time and then fill it up again, which is the gas station model. Right? And so people have taken that over into thinking about batteries, right? To charge up the batteries and then you drive around for a long time and then you charge them up again. 

Our view is quite different. I am going to glide over some fairly complex technical issues here, but the basic idea here is to recharge every time you park. So I think of parking spaces as being like the holder of your electric toothbrush. You know, you drop your electric toothbrush back in the holder and it automatically recharges. And you never think about recharging the toothbrush and it’s never without charge because whenever you are not using it, it’s just picking up charge. So, imagine a kind of system where you have lightweight electric vehicles relatively small battery capacity, and then picking up charge wherever they park. So, that is an interesting user model you can begin to understand from a user’s point of view how that can work. You never have to worry about filling up your car, never go to the gas station, never plug it in, never do any of these things. 

From the point of view of sustainability and the electric grid it has a whole other set of advantages because if you do this, you throw a lot of battery storage capacity into the electric grid. Part of the problem with electric grids is they don’t have a lot of storage capacity; usually they don’t have any storage capacity, which means you have a problem with peak loading. And once again, it’s a balancing problem. You have to size the grid to deal with that hot summer day when everybody has turned their air conditioning on. But the rest of the time you have over capacity if you size it for that. This is oversimplifying a complex issue. But you get the idea.

And then there is also a problem with the intermittency. Clean power sources like solar and wind particularly don’t necessarily supply electricity when you need it. The wind doesn’t necessarily blow when you want the electricity, the sun doesn’t necessarily shine. But if you have storage capacity in the grid and then you set it up so that automobiles can buy and sell electricity from their battery’s storage, they become little energy traders essentially. This gives you a mechanism for balancing the electrical grid and for making clean that intermittent power sources as much more cost effective. So, you see with all of these issues, I think you have to look at them from multiple points of view simultaneously. So, from one point of view, the strategy of electric charging we’re looking at is just convenience, for the convenience of the user. From another point of view, it’s a strategy for making the grid much more friendly to clean, green electric sources. You always want to look for these win, wins in design.

Recorded on January 21, 2010

Bill Mitchell envisions cars that you’ll never have to worry about filling up or plugging in.

LinkedIn meets Tinder in this mindful networking app

Swipe right to make the connections that could change your career.

Getty Images
Sponsored
Swipe right. Match. Meet over coffee or set up a call.

No, we aren't talking about Tinder. Introducing Shapr, a free app that helps people with synergistic professional goals and skill sets easily meet and collaborate.

Keep reading Show less

Space toilets: How astronauts boldly go where few have gone before

A NASA astronomer explains how astronauts dispose of their, uh, dark matter.

Videos
  • When nature calls in micro-gravity, astronauts must answer. Space agencies have developed suction-based toilets – with a camera built in to ensure all the waste is contained before "flushing".
  • Yes, there have been floaters in space. The early days of space exploration were a learning curve!
  • Amazingly, you don't need gravity to digest food. Peristalsis, the process by which your throat and intestines squeeze themselves, actually moves food and water through your digestive system without gravity at all.
Keep reading Show less

A world map of Virgin Mary apparitions

She met mere mortals with and without the Vatican's approval.

Strange Maps
  • For centuries, the Virgin Mary has appeared to the faithful, requesting devotion and promising comfort.
  • These maps show the geography of Marian apparitions – the handful approved by the Vatican, and many others.
  • Historically, Europe is where most apparitions have been reported, but the U.S. is pretty fertile ground too.
Keep reading Show less

Can the keto diet help treat depression? Here’s what the science says so far

A growing body of research shows promising signs that the keto diet might be able to improve mental health.

Public Domain
Mind & Brain
  • The keto diet is known to be an effective tool for weight loss, however its effects on mental health remain largely unclear.
  • Recent studies suggests that the keto diet might be an effective tool for treating depression, and clearing up so-called "brain fog," though scientists caution more research is necessary before it can be recommended as a treatment.
  • Any experiments with the keto diet are best done in conjunction with a doctor, considering some people face problems when transitioning to the low-carb diet.
Keep reading Show less